build(deps): bump cloud.google.com/go/storage from 1.16.0 to 1.16.1 (#1589)

Bumps [cloud.google.com/go/storage](https://github.com/googleapis/google-cloud-go) from 1.16.0 to 1.16.1.
- [Release notes](https://github.com/googleapis/google-cloud-go/releases)
- [Changelog](https://github.com/googleapis/google-cloud-go/blob/master/CHANGES.md)
- [Commits](https://github.com/googleapis/google-cloud-go/compare/pubsub/v1.16.0...storage/v1.16.1)

---
updated-dependencies:
- dependency-name: cloud.google.com/go/storage
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

go.mod

@@ -1,7 +1,7 @@
 module github.com/VictoriaMetrics/VictoriaMetrics
 
 require (
-	cloud.google.com/go/storage v1.16.0
+	cloud.google.com/go/storage v1.16.1
 	github.com/VictoriaMetrics/fastcache v1.6.0
 
 	// Do not use the original github.com/valyala/fasthttp because of issues

go.sum

@@ -45,8 +45,8 @@ cloud.google.com/go/storage v1.5.0/go.mod h1:tpKbwo567HUNpVclU5sGELwQWBDZ8gh0Zeo
 cloud.google.com/go/storage v1.6.0/go.mod h1:N7U0C8pVQ/+NIKOBQyamJIeKQKkZ+mxpohlUTyfDhBk=
 cloud.google.com/go/storage v1.8.0/go.mod h1:Wv1Oy7z6Yz3DshWRJFhqM/UCfaWIRTdp0RXyy7KQOVs=
 cloud.google.com/go/storage v1.10.0/go.mod h1:FLPqc6j+Ki4BU591ie1oL6qBQGu2Bl/tZ9ullr3+Kg0=
-cloud.google.com/go/storage v1.16.0 h1:1UwAux2OZP4310YXg5ohqBEpV16Y93uZG4+qOX7K2Kg=
+cloud.google.com/go/storage v1.16.1 h1:sMEIc4wxvoY3NXG7Rn9iP7jb/2buJgWR1vNXCR/UPfs=
-cloud.google.com/go/storage v1.16.0/go.mod h1:ieKBmUyzcftN5tbxwnXClMKH00CfcQ+xL6NN0r5QfmE=
+cloud.google.com/go/storage v1.16.1/go.mod h1:LaNorbty3ehnU3rEjXSNV/NRgQA0O8Y+uh6bPe5UOk4=
 collectd.org v0.3.0/go.mod h1:A/8DzQBkF6abtvrT2j/AU/4tiBgJWYyh0y/oB/4MlWE=
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
 github.com/Azure/azure-sdk-for-go v41.3.0+incompatible/go.mod h1:9XXNKU+eRnpl9moKnB4QOLf1HestfXbmab5FXxiDBjc=
@@ -1125,7 +1125,6 @@ golang.org/x/oauth2 v0.0.0-20210218202405-ba52d332ba99/go.mod h1:KelEdhl1UZF7XfJ
 golang.org/x/oauth2 v0.0.0-20210220000619-9bb904979d93/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20210313182246-cd4f82c27b84/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
-golang.org/x/oauth2 v0.0.0-20210615190721-d04028783cf1/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20210628180205-a41e5a781914/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20210805134026-6f1e6394065a/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20210819190943-2bc19b11175f h1:Qmd2pbz05z7z6lm0DrgQVVPuBm92jqujBKMHMOlOQEw=
@@ -1370,7 +1369,6 @@ google.golang.org/api v0.41.0/go.mod h1:RkxM5lITDfTzmyKFPt+wGrCJbVfniCr2ool8kTBz
 google.golang.org/api v0.43.0/go.mod h1:nQsDGjRXMo4lvh5hP0TKqF244gqhGcr/YSIykhUk/94=
 google.golang.org/api v0.47.0/go.mod h1:Wbvgpq1HddcWVtzsVLyfLp8lDg6AA241LmgIL59tHXo=
 google.golang.org/api v0.48.0/go.mod h1:71Pr1vy+TAZRPkPs/xlCf5SsU8WjuAWv1Pfjbtukyy4=
-google.golang.org/api v0.49.0/go.mod h1:BECiH72wsfwUvOVn3+btPD5WHi0LzavZReBndi42L18=
 google.golang.org/api v0.50.0/go.mod h1:4bNT5pAuq5ji4SRZm+5QIkjny9JAyVD/3gaSihNefaw=
 google.golang.org/api v0.51.0/go.mod h1:t4HdrdoNgyN5cbEfm7Lum0lcLDLiise1F8qDKX00sOU=
 google.golang.org/api v0.54.0/go.mod h1:7C4bFFOvVDGXjfDTAsgGwDgAxRDeQ4X8NvUedIt6z3k=
@@ -1434,8 +1432,6 @@ google.golang.org/genproto v0.0.0-20210513213006-bf773b8c8384/go.mod h1:P3QM42oQ
 google.golang.org/genproto v0.0.0-20210602131652-f16073e35f0c/go.mod h1:UODoCrxHCcBojKKwX1terBiRUaqAsFqJiF615XL43r0=
 google.golang.org/genproto v0.0.0-20210604141403-392c879c8b08/go.mod h1:UODoCrxHCcBojKKwX1terBiRUaqAsFqJiF615XL43r0=
 google.golang.org/genproto v0.0.0-20210608205507-b6d2f5bf0d7d/go.mod h1:UODoCrxHCcBojKKwX1terBiRUaqAsFqJiF615XL43r0=
-google.golang.org/genproto v0.0.0-20210617175327-b9e0b3197ced/go.mod h1:SzzZ/N+nwJDaO1kznhnlzqS8ocJICar6hYhVyhi++24=
-google.golang.org/genproto v0.0.0-20210624174822-c5cf32407d0a/go.mod h1:SzzZ/N+nwJDaO1kznhnlzqS8ocJICar6hYhVyhi++24=
 google.golang.org/genproto v0.0.0-20210624195500-8bfb893ecb84/go.mod h1:SzzZ/N+nwJDaO1kznhnlzqS8ocJICar6hYhVyhi++24=
 google.golang.org/genproto v0.0.0-20210713002101-d411969a0d9a/go.mod h1:AxrInvYm1dci+enl5hChSFPOmmUF1+uAa/UsgNRWd7k=
 google.golang.org/genproto v0.0.0-20210716133855-ce7ef5c701ea/go.mod h1:AxrInvYm1dci+enl5hChSFPOmmUF1+uAa/UsgNRWd7k=
@@ -1443,6 +1439,7 @@ google.golang.org/genproto v0.0.0-20210728212813-7823e685a01f/go.mod h1:ob2IJxKr
 google.golang.org/genproto v0.0.0-20210805201207-89edb61ffb67/go.mod h1:ob2IJxKrgPT52GcgX759i1sleT07tiKowYBGbczaW48=
 google.golang.org/genproto v0.0.0-20210813162853-db860fec028c/go.mod h1:cFeNkxwySK631ADgubI+/XFU/xp8FD5KIVV4rj8UC5w=
 google.golang.org/genproto v0.0.0-20210821163610-241b8fcbd6c8/go.mod h1:eFjDcFEctNawg4eG61bRv87N7iHBWyVhJu7u1kqDUXY=
+google.golang.org/genproto v0.0.0-20210825212027-de86158e7fda/go.mod h1:eFjDcFEctNawg4eG61bRv87N7iHBWyVhJu7u1kqDUXY=
 google.golang.org/genproto v0.0.0-20210828152312-66f60bf46e71/go.mod h1:eFjDcFEctNawg4eG61bRv87N7iHBWyVhJu7u1kqDUXY=
 google.golang.org/genproto v0.0.0-20210831024726-fe130286e0e2 h1:NHN4wOCScVzKhPenJ2dt+BTs3X/XkBVI/Rh4iDt55T8=
 google.golang.org/genproto v0.0.0-20210831024726-fe130286e0e2/go.mod h1:eFjDcFEctNawg4eG61bRv87N7iHBWyVhJu7u1kqDUXY=

vendor/cloud.google.com/go/storage/CHANGES.md

@@ -1,5 +1,17 @@
 # Changes
 
+### [1.16.1](https://www.github.com/googleapis/google-cloud-go/compare/storage/v1.16.0...storage/v1.16.1) (2021-08-30)
+
+
+### Bug Fixes
+
+* **storage/internal:** Update encryption_key fields to "bytes" type. fix: Improve date/times and field name clarity in lifecycle conditions. ([a52baa4](https://www.github.com/googleapis/google-cloud-go/commit/a52baa456ed8513ec492c4b573c191eb61468758))
+* **storage:** accept emulator env var without scheme ([#4616](https://www.github.com/googleapis/google-cloud-go/issues/4616)) ([5f8cbb9](https://www.github.com/googleapis/google-cloud-go/commit/5f8cbb98070109e2a34409ac775ed63b94d37efd))
+* **storage:** preserve supplied endpoint's scheme ([#4609](https://www.github.com/googleapis/google-cloud-go/issues/4609)) ([ee2756f](https://www.github.com/googleapis/google-cloud-go/commit/ee2756fb0a335d591464a770c9fa4f8fe0ba2e01))
+* **storage:** remove unnecessary variable ([#4608](https://www.github.com/googleapis/google-cloud-go/issues/4608)) ([27fc784](https://www.github.com/googleapis/google-cloud-go/commit/27fc78456fb251652bdf5cdb493734a7e1e643e1))
+* **storage:** retry LockRetentionPolicy ([#4439](https://www.github.com/googleapis/google-cloud-go/issues/4439)) ([09879ea](https://www.github.com/googleapis/google-cloud-go/commit/09879ea80cb67f9bfd8fc9384b0fda335567cba9)), refs [#4437](https://www.github.com/googleapis/google-cloud-go/issues/4437)
+* **storage:** revise Reader to send XML preconditions ([#4479](https://www.github.com/googleapis/google-cloud-go/issues/4479)) ([e36b29a](https://www.github.com/googleapis/google-cloud-go/commit/e36b29a3d43bce5c1c044f7daf6e1db00b0a49e0)), refs [#4470](https://www.github.com/googleapis/google-cloud-go/issues/4470)
+
 ## [1.16.0](https://www.github.com/googleapis/google-cloud-go/compare/storage/v1.15.0...storage/v1.16.0) (2021-06-28)
 
 

vendor/cloud.google.com/go/storage/acl.go

@@ -22,6 +22,7 @@ import (
 	"cloud.google.com/go/internal/trace"
 	"google.golang.org/api/googleapi"
 	raw "google.golang.org/api/storage/v1"
+	storagepb "google.golang.org/genproto/googleapis/storage/v2"
 )
 
 // ACLRole is the level of access to grant.
@@ -244,6 +245,14 @@ func toObjectACLRules(items []*raw.ObjectAccessControl) []ACLRule {
 	return rs
 }
 
+func fromProtoToObjectACLRules(items []*storagepb.ObjectAccessControl) []ACLRule {
+	var rs []ACLRule
+	for _, item := range items {
+		rs = append(rs, fromProtoToObjectACLRule(item))
+	}
+	return rs
+}
+
 func toBucketACLRules(items []*raw.BucketAccessControl) []ACLRule {
 	var rs []ACLRule
 	for _, item := range items {
@@ -263,6 +272,17 @@ func toObjectACLRule(a *raw.ObjectAccessControl) ACLRule {
 	}
 }
 
+func fromProtoToObjectACLRule(a *storagepb.ObjectAccessControl) ACLRule {
+	return ACLRule{
+		Entity:      ACLEntity(a.GetEntity()),
+		EntityID:    a.GetEntityId(),
+		Role:        ACLRole(a.GetRole()),
+		Domain:      a.GetDomain(),
+		Email:       a.GetEmail(),
+		ProjectTeam: fromProtoToObjectProjectTeam(a.GetProjectTeam()),
+	}
+}
+
 func toBucketACLRule(a *raw.BucketAccessControl) ACLRule {
 	return ACLRule{
 		Entity:      ACLEntity(a.Entity),
@@ -285,6 +305,17 @@ func toRawObjectACL(rules []ACLRule) []*raw.ObjectAccessControl {
 	return r
 }
 
+func toProtoObjectACL(rules []ACLRule) []*storagepb.ObjectAccessControl {
+	if len(rules) == 0 {
+		return nil
+	}
+	r := make([]*storagepb.ObjectAccessControl, 0, len(rules))
+	for _, rule := range rules {
+		r = append(r, rule.toProtoObjectAccessControl("")) // bucket name unnecessary
+	}
+	return r
+}
+
 func toRawBucketACL(rules []ACLRule) []*raw.BucketAccessControl {
 	if len(rules) == 0 {
 		return nil
@@ -314,6 +345,14 @@ func (r ACLRule) toRawObjectAccessControl(bucket string) *raw.ObjectAccessContro
 	}
 }
 
+func (r ACLRule) toProtoObjectAccessControl(bucket string) *storagepb.ObjectAccessControl {
+	return &storagepb.ObjectAccessControl{
+		Entity: string(r.Entity),
+		Role:   string(r.Role),
+		// The other fields are not settable.
+	}
+}
+
 func toBucketProjectTeam(p *raw.BucketAccessControlProjectTeam) *ProjectTeam {
 	if p == nil {
 		return nil
@@ -333,3 +372,13 @@ func toObjectProjectTeam(p *raw.ObjectAccessControlProjectTeam) *ProjectTeam {
 		Team:          p.Team,
 	}
 }
+
+func fromProtoToObjectProjectTeam(p *storagepb.ProjectTeam) *ProjectTeam {
+	if p == nil {
+		return nil
+	}
+	return &ProjectTeam{
+		ProjectNumber: p.GetProjectNumber(),
+		Team:          p.GetTeam(),
+	}
+}

vendor/cloud.google.com/go/storage/bucket.go

@@ -130,7 +130,8 @@ func (b *BucketHandle) DefaultObjectACL() *ACLHandle {
 }
 
 // Object returns an ObjectHandle, which provides operations on the named object.
-// This call does not perform any network operations.
+// This call does not perform any network operations such as fetching the object or verifying its existence.
+// Use methods on ObjectHandle to perform network operations.
 //
 // name must consist entirely of valid UTF-8-encoded runes. The full specification
 // for valid object names can be found at:
@@ -949,8 +950,10 @@ func (b *BucketHandle) LockRetentionPolicy(ctx context.Context) error {
 		metageneration = b.conds.MetagenerationMatch
 	}
 	req := b.c.raw.Buckets.LockRetentionPolicy(b.name, metageneration)
-	_, err := req.Context(ctx).Do()
+	return runWithRetry(ctx, func() error {
-	return err
+		_, err := req.Context(ctx).Do()
+		return err
+	})
 }
 
 // applyBucketConds modifies the provided call using the conditions in conds.

vendor/cloud.google.com/go/storage/doc.go

@@ -48,6 +48,31 @@ an unauthenticated client with
 
     client, err := storage.NewClient(ctx, option.WithoutAuthentication())
 
+To use an emulator with this library, you can set the STORAGE_EMULATOR_HOST
+environment variable to the address at which your emulator is running. This will
+send requests to that address instead of to Cloud Storage. You can then create
+and use a client as usual:
+
+    // Set STORAGE_EMULATOR_HOST environment variable.
+    err := os.Setenv("STORAGE_EMULATOR_HOST", "localhost:9000")
+    if err != nil {
+        // TODO: Handle error.
+    }
+
+    // Create client as usual.
+    client, err := storage.NewClient(ctx)
+    if err != nil {
+        // TODO: Handle error.
+    }
+
+    // This request is now directed to http://localhost:9000/storage/v1/b
+    // instead of https://storage.googleapis.com/storage/v1/b
+    if err := client.Bucket("my-bucket").Create(ctx, projectID, nil); err != nil {
+        // TODO: Handle error.
+    }
+
+Please note that there is no official emulator for Cloud Storage.
+
 Buckets
 
 A Google Cloud Storage bucket is a collection of objects. To work with a

vendor/cloud.google.com/go/storage/go.mod

@@ -3,13 +3,14 @@ module cloud.google.com/go/storage
 go 1.11
 
 require (
-	cloud.google.com/go v0.84.0
+	cloud.google.com/go v0.93.3
 	github.com/golang/protobuf v1.5.2
 	github.com/google/go-cmp v0.5.6
 	github.com/googleapis/gax-go/v2 v2.0.5
-	golang.org/x/oauth2 v0.0.0-20210615190721-d04028783cf1
+	golang.org/x/oauth2 v0.0.0-20210805134026-6f1e6394065a
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1
-	google.golang.org/api v0.49.0
+	google.golang.org/api v0.54.0
-	google.golang.org/genproto v0.0.0-20210624174822-c5cf32407d0a
+	google.golang.org/genproto v0.0.0-20210825212027-de86158e7fda
-	google.golang.org/grpc v1.38.0
+	google.golang.org/grpc v1.40.0
+	google.golang.org/protobuf v1.27.1
 )

vendor/cloud.google.com/go/storage/go.sum

@@ -19,8 +19,11 @@ cloud.google.com/go v0.78.0/go.mod h1:QjdrLG0uq+YwhjoVOLsS1t7TW8fs36kLs4XO5R5ECH
 cloud.google.com/go v0.79.0/go.mod h1:3bzgcEeQlzbuEAYu4mrWhKqWjmpprinYgKJLgKHnbb8=
 cloud.google.com/go v0.81.0/go.mod h1:mk/AM35KwGk/Nm2YSeZbxXdrNK3KZOYHmLkOqC2V6E0=
 cloud.google.com/go v0.83.0/go.mod h1:Z7MJUsANfY0pYPdw0lbnivPx4/vhy/e2FEkSkF7vAVY=
-cloud.google.com/go v0.84.0 h1:hVhK90DwCdOAYGME/FJd9vNIZye9HBR6Yy3fu4js3N8=
 cloud.google.com/go v0.84.0/go.mod h1:RazrYuxIK6Kb7YrzzhPoLmCVzl7Sup4NrbKPg8KHSUM=
+cloud.google.com/go v0.87.0/go.mod h1:TpDYlFy7vuLzZMMZ+B6iRiELaY7z/gJPaqbMx6mlWcY=
+cloud.google.com/go v0.90.0/go.mod h1:kRX0mNRHe0e2rC6oNakvwQqzyDmg57xJ+SZU1eT2aDQ=
+cloud.google.com/go v0.93.3 h1:wPBktZFzYBcCZVARvwVKqH1uEj+aLXofJEtrb4oOsio=
+cloud.google.com/go v0.93.3/go.mod h1:8utlLll2EF5XMAV15woO4lSbWQlk8rer9aLOfLh7+YI=
 cloud.google.com/go/bigquery v1.0.1/go.mod h1:i/xbL2UlR5RvWAURpBYZTtm/cXjCha9lbfbpx4poX+o=
 cloud.google.com/go/bigquery v1.3.0/go.mod h1:PjpwJnslEMmckchkHFfq+HTD2DmtT67aNFKH1/VBDHE=
 cloud.google.com/go/bigquery v1.4.0/go.mod h1:S8dzgnTigyfTmLBfrtrhyYhwRxG72rYxvftPBK2Dvzc=
@@ -41,7 +44,10 @@ cloud.google.com/go/storage v1.10.0/go.mod h1:FLPqc6j+Ki4BU591ie1oL6qBQGu2Bl/tZ9
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
+github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
+github.com/antihax/optional v1.0.0/go.mod h1:uupD/76wgC+ih3iEmQUL+0Ugr19nfwCT1kdvxnR2qWY=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
+github.com/cespare/xxhash v1.1.0/go.mod h1:XrSqR1VqqWfGrhpAt58auRo0WTKS1nRRg3ghfAqPWnc=
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
 github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
@@ -49,6 +55,7 @@ github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDk
 github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
 github.com/cncf/udpa/go v0.0.0-20200629203442-efcf912fb354/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
 github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
+github.com/cncf/xds/go v0.0.0-20210312221358-fbca930ec8ed/go.mod h1:eXthEFrGJvWHgFFCl3hGmgk+/aYT6PnTQLykKQRLhEs=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/envoyproxy/go-control-plane v0.9.0/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
 github.com/envoyproxy/go-control-plane v0.9.1-0.20191026205805-5f8ba28d4473/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
@@ -56,7 +63,9 @@ github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1m
 github.com/envoyproxy/go-control-plane v0.9.7/go.mod h1:cwu0lG7PUMfa9snN8LXBig5ynNVH9qI8YYLbd1fK2po=
 github.com/envoyproxy/go-control-plane v0.9.9-0.20201210154907-fd9021fe5dad/go.mod h1:cXg6YxExXjJnVBQHBLXeUAgxn2UodCpnH306RInaBQk=
 github.com/envoyproxy/go-control-plane v0.9.9-0.20210217033140-668b12f5399d/go.mod h1:cXg6YxExXjJnVBQHBLXeUAgxn2UodCpnH306RInaBQk=
+github.com/envoyproxy/go-control-plane v0.9.9-0.20210512163311-63b5d3c536b0/go.mod h1:hliV/p42l8fGbc6Y9bQ70uLwIvmJyVE5k4iMKlh8wCQ=
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
+github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
@@ -73,6 +82,7 @@ github.com/golang/mock v1.4.1/go.mod h1:UOMv5ysSaYNkG+OFQykRIcU/QvvxJf3p21QfJ2Bt
 github.com/golang/mock v1.4.3/go.mod h1:UOMv5ysSaYNkG+OFQykRIcU/QvvxJf3p21QfJ2Bt3cw=
 github.com/golang/mock v1.4.4/go.mod h1:l3mdAwkq5BuhzHwde/uurv3sEJeZMXNpwsxVWU71h+4=
 github.com/golang/mock v1.5.0/go.mod h1:CWnOUgYIOo4TcNZ0wHX3YZCqsaM1I1Jvs6v3mP3KVu8=
+github.com/golang/mock v1.6.0/go.mod h1:p6yTPP+5HYm5mzsMV8JkE6ZKdX+/wYM6Hr+LicevLPs=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
@@ -126,17 +136,19 @@ github.com/google/pprof v0.0.0-20201203190320-1bf35d6f28c2/go.mod h1:kpwsk12EmLe
 github.com/google/pprof v0.0.0-20210122040257-d980be63207e/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/pprof v0.0.0-20210226084205-cbba55b83ad5/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/pprof v0.0.0-20210601050228-01bbb1931b22/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
+github.com/google/pprof v0.0.0-20210609004039-a478d1d731e9/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
+github.com/google/pprof v0.0.0-20210720184732-4bb14d4b1be1/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
 github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5 h1:sjZBwGj9Jlw33ImPtvFviGYvseOtDM7hkSKB7+Tv3SM=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
+github.com/grpc-ecosystem/grpc-gateway v1.16.0/go.mod h1:BDjrQk3hbvj6Nolgz8mAMFbcEtjT1g+wF4CSlocrBnw=
 github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hashicorp/golang-lru v0.5.1/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/ianlancetaylor/demangle v0.0.0-20181102032728-5e5cf60278f6/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
 github.com/ianlancetaylor/demangle v0.0.0-20200824232613-28f6c0f3b639/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
-github.com/jstemmer/go-junit-report v0.9.1 h1:6QPYqodiu3GuPL+7mfx+NwDdp2eTkp9IfEUpgAwUN0o=
 github.com/jstemmer/go-junit-report v0.9.1/go.mod h1:Brl9GWCQeLvo8nXZwPNNblvFj/XSXhF0NWZEnDohbsk=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
@@ -144,7 +156,9 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
+github.com/rogpeppe/fastuuid v1.2.0/go.mod h1:jVj6XXZzXRy/MSR5jhDC/2q6DgLz+nrA6LYCDYWNEvQ=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
+github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
@@ -162,6 +176,7 @@ go.opencensus.io v0.22.4/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
 go.opencensus.io v0.22.5/go.mod h1:5pWMHQbX5EPX2/62yrJeAkowc+lfs/XD7Uxpq3pI6kk=
 go.opencensus.io v0.23.0 h1:gqCw0LfLxScz8irSi8exQc7fyQ0fKQU/qnC/X8+V/1M=
 go.opencensus.io v0.23.0/go.mod h1:XItmlyltB5F7CS4xOC1DcqMoFqwtC6OG2xF7mCv7P7E=
+go.opentelemetry.io/proto/otlp v0.7.0/go.mod h1:PqfVotwruBrMGOCsRd/89rSnXhoiJIqeYNgFYFoEGnI=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20190605123033-f99c8df09eb5/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
@@ -190,7 +205,6 @@ golang.org/x/lint v0.0.0-20191125180803-fdd1cda4f05f/go.mod h1:5qLYkcX4OjUUV8bRu
 golang.org/x/lint v0.0.0-20200130185559-910be7a94367/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/lint v0.0.0-20200302205851-738671d3881b/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
-golang.org/x/lint v0.0.0-20210508222113-6edffad5e616 h1:VLliZ0d+/avPrXXH+OakdXhpJuEoBZuwh1m2j7U6Iug=
 golang.org/x/lint v0.0.0-20210508222113-6edffad5e616/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/mobile v0.0.0-20190312151609-d3739f865fa6/go.mod h1:z+o9i4GpDbdi3rU15maQ/Ox0txvL9dWGYEHz965HBQE=
 golang.org/x/mobile v0.0.0-20190719004257-d2bd2a29d028/go.mod h1:E/iHnbuqvinMTCcRqshq8CkpyQDoeVncDDYHnLhea+o=
@@ -202,7 +216,6 @@ golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.1/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/mod v0.4.2 h1:Gz96sIWK3OalVv/I/qNygP42zyoKp3xptRVCWRFEBvo=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -252,8 +265,9 @@ golang.org/x/oauth2 v0.0.0-20210218202405-ba52d332ba99/go.mod h1:KelEdhl1UZF7XfJ
 golang.org/x/oauth2 v0.0.0-20210220000619-9bb904979d93/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20210313182246-cd4f82c27b84/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
-golang.org/x/oauth2 v0.0.0-20210615190721-d04028783cf1 h1:x622Z2o4hgCr/4CiKWc51jHVKaWdtVpBNmEI8wI9Qns=
+golang.org/x/oauth2 v0.0.0-20210628180205-a41e5a781914/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
-golang.org/x/oauth2 v0.0.0-20210615190721-d04028783cf1/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
+golang.org/x/oauth2 v0.0.0-20210805134026-6f1e6394065a h1:4Kd8OPUx1xgUwrHDaviWZO8MsgoZTZYC3g+8m16RBww=
+golang.org/x/oauth2 v0.0.0-20210805134026-6f1e6394065a/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -305,8 +319,10 @@ golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210514084401-e8d321eab015/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210603125802-9665404d3644/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20210616094352-59db8d763f22 h1:RqytpXGR1iVNX7psjB3ff8y7sNFinVFvkx1c8SjBkio=
 golang.org/x/sys v0.0.0-20210616094352-59db8d763f22/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210806184541-e5e7981a1069 h1:siQdpVirKtzPhKl3lZWozZraCFObP8S1v6PRp0bLrtU=
+golang.org/x/sys v0.0.0-20210806184541-e5e7981a1069/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -368,8 +384,9 @@ golang.org/x/tools v0.0.0-20210105154028-b0ab187a4818/go.mod h1:emZCQorbCU4vsT4f
 golang.org/x/tools v0.1.0/go.mod h1:xkSsbof2nBLbhDlRMhhhyNLN/zl3eTqcnHD5viDpcZ0=
 golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.2/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
-golang.org/x/tools v0.1.3 h1:L69ShwSZEyCsLKoAxDKeMvLDZkumEe8gXUZAjab0tX8=
 golang.org/x/tools v0.1.3/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
+golang.org/x/tools v0.1.4/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
+golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
@@ -398,8 +415,10 @@ google.golang.org/api v0.41.0/go.mod h1:RkxM5lITDfTzmyKFPt+wGrCJbVfniCr2ool8kTBz
 google.golang.org/api v0.43.0/go.mod h1:nQsDGjRXMo4lvh5hP0TKqF244gqhGcr/YSIykhUk/94=
 google.golang.org/api v0.47.0/go.mod h1:Wbvgpq1HddcWVtzsVLyfLp8lDg6AA241LmgIL59tHXo=
 google.golang.org/api v0.48.0/go.mod h1:71Pr1vy+TAZRPkPs/xlCf5SsU8WjuAWv1Pfjbtukyy4=
-google.golang.org/api v0.49.0 h1:gjIBDxlTG7vnzMmEnYwTnvLTF8Rjzo+ETCgEX1YZ/fY=
+google.golang.org/api v0.50.0/go.mod h1:4bNT5pAuq5ji4SRZm+5QIkjny9JAyVD/3gaSihNefaw=
-google.golang.org/api v0.49.0/go.mod h1:BECiH72wsfwUvOVn3+btPD5WHi0LzavZReBndi42L18=
+google.golang.org/api v0.51.0/go.mod h1:t4HdrdoNgyN5cbEfm7Lum0lcLDLiise1F8qDKX00sOU=
+google.golang.org/api v0.54.0 h1:ECJUVngj71QI6XEm7b1sAf8BljU5inEhMbKPR8Lxhhk=
+google.golang.org/api v0.54.0/go.mod h1:7C4bFFOvVDGXjfDTAsgGwDgAxRDeQ4X8NvUedIt6z3k=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/appengine v1.5.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
@@ -431,6 +450,7 @@ google.golang.org/genproto v0.0.0-20200312145019-da6875a35672/go.mod h1:55QSHmfG
 google.golang.org/genproto v0.0.0-20200331122359-1ee6d9798940/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
 google.golang.org/genproto v0.0.0-20200430143042-b979b6f78d84/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
 google.golang.org/genproto v0.0.0-20200511104702-f5ebc3bea380/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
+google.golang.org/genproto v0.0.0-20200513103714-09dca8ec2884/go.mod h1:55QSHmfGQM9UVYDPBsyGGes0y52j32PQ3BqQfXhyH3c=
 google.golang.org/genproto v0.0.0-20200515170657-fc4c6c6a6587/go.mod h1:YsZOwe1myG/8QRHRsmBRE1LrgQY60beZKjly0O1fX9U=
 google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013/go.mod h1:NbSheEEYHJ7i3ixzK3sjbqSGDJWnxyFXZblF3eUsNvo=
 google.golang.org/genproto v0.0.0-20200618031413-b414f8b61790/go.mod h1:jDfRM7FcilCzHH/e9qn6dsT145K34l5v+OpcnNgKAAA=
@@ -451,9 +471,14 @@ google.golang.org/genproto v0.0.0-20210513213006-bf773b8c8384/go.mod h1:P3QM42oQ
 google.golang.org/genproto v0.0.0-20210602131652-f16073e35f0c/go.mod h1:UODoCrxHCcBojKKwX1terBiRUaqAsFqJiF615XL43r0=
 google.golang.org/genproto v0.0.0-20210604141403-392c879c8b08/go.mod h1:UODoCrxHCcBojKKwX1terBiRUaqAsFqJiF615XL43r0=
 google.golang.org/genproto v0.0.0-20210608205507-b6d2f5bf0d7d/go.mod h1:UODoCrxHCcBojKKwX1terBiRUaqAsFqJiF615XL43r0=
-google.golang.org/genproto v0.0.0-20210617175327-b9e0b3197ced/go.mod h1:SzzZ/N+nwJDaO1kznhnlzqS8ocJICar6hYhVyhi++24=
+google.golang.org/genproto v0.0.0-20210624195500-8bfb893ecb84/go.mod h1:SzzZ/N+nwJDaO1kznhnlzqS8ocJICar6hYhVyhi++24=
-google.golang.org/genproto v0.0.0-20210624174822-c5cf32407d0a h1:b5Bhxmy6Tppar7Yl4J6c6xF33YSBhkm2FtV9/ZQuBkQ=
+google.golang.org/genproto v0.0.0-20210713002101-d411969a0d9a/go.mod h1:AxrInvYm1dci+enl5hChSFPOmmUF1+uAa/UsgNRWd7k=
-google.golang.org/genproto v0.0.0-20210624174822-c5cf32407d0a/go.mod h1:SzzZ/N+nwJDaO1kznhnlzqS8ocJICar6hYhVyhi++24=
+google.golang.org/genproto v0.0.0-20210716133855-ce7ef5c701ea/go.mod h1:AxrInvYm1dci+enl5hChSFPOmmUF1+uAa/UsgNRWd7k=
+google.golang.org/genproto v0.0.0-20210728212813-7823e685a01f/go.mod h1:ob2IJxKrgPT52GcgX759i1sleT07tiKowYBGbczaW48=
+google.golang.org/genproto v0.0.0-20210805201207-89edb61ffb67/go.mod h1:ob2IJxKrgPT52GcgX759i1sleT07tiKowYBGbczaW48=
+google.golang.org/genproto v0.0.0-20210813162853-db860fec028c/go.mod h1:cFeNkxwySK631ADgubI+/XFU/xp8FD5KIVV4rj8UC5w=
+google.golang.org/genproto v0.0.0-20210825212027-de86158e7fda h1:iT5uhT54PtbqUsWddv/nnEWdE5e/MTr+Nv3vjxlBP1A=
+google.golang.org/genproto v0.0.0-20210825212027-de86158e7fda/go.mod h1:eFjDcFEctNawg4eG61bRv87N7iHBWyVhJu7u1kqDUXY=
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 google.golang.org/grpc v1.20.1/go.mod h1:10oTOabMzJvdu6/UiuZezV6QK5dSlG84ov/aaiqXj38=
 google.golang.org/grpc v1.21.1/go.mod h1:oYelfM1adQP15Ek0mdvEgi9Df8B9CZIaU1084ijfRaM=
@@ -467,6 +492,7 @@ google.golang.org/grpc v1.29.1/go.mod h1:itym6AZVZYACWQqET3MqgPpjcuV5QH3BxFS3Iji
 google.golang.org/grpc v1.30.0/go.mod h1:N36X2cJ7JwdamYAgDz+s+rVMFjt3numwzf/HckM8pak=
 google.golang.org/grpc v1.31.0/go.mod h1:N36X2cJ7JwdamYAgDz+s+rVMFjt3numwzf/HckM8pak=
 google.golang.org/grpc v1.31.1/go.mod h1:N36X2cJ7JwdamYAgDz+s+rVMFjt3numwzf/HckM8pak=
+google.golang.org/grpc v1.33.1/go.mod h1:fr5YgcSWrqhRRxogOsw7RzIpsmvOZ6IcH4kBYTpR3n0=
 google.golang.org/grpc v1.33.2/go.mod h1:JMHMWHQWaTccqQQlmk3MJZS+GWXOdAesneDmEnv2fbc=
 google.golang.org/grpc v1.34.0/go.mod h1:WotjhfgOW/POjDeRt8vscBtXq+2VjORFy659qA51WJ8=
 google.golang.org/grpc v1.35.0/go.mod h1:qjiiYl8FncCW8feJPdyg3v6XW24KsRHe+dy9BAGRRjU=
@@ -474,8 +500,11 @@ google.golang.org/grpc v1.36.0/go.mod h1:qjiiYl8FncCW8feJPdyg3v6XW24KsRHe+dy9BAG
 google.golang.org/grpc v1.36.1/go.mod h1:qjiiYl8FncCW8feJPdyg3v6XW24KsRHe+dy9BAGRRjU=
 google.golang.org/grpc v1.37.0/go.mod h1:NREThFqKR1f3iQ6oBuvc5LadQuXVGo9rkm5ZGrQdJfM=
 google.golang.org/grpc v1.37.1/go.mod h1:NREThFqKR1f3iQ6oBuvc5LadQuXVGo9rkm5ZGrQdJfM=
-google.golang.org/grpc v1.38.0 h1:/9BgsAsa5nWe26HqOlvlgJnqBuktYOLCgjCPqsa56W0=
 google.golang.org/grpc v1.38.0/go.mod h1:NREThFqKR1f3iQ6oBuvc5LadQuXVGo9rkm5ZGrQdJfM=
+google.golang.org/grpc v1.39.0/go.mod h1:PImNr+rS9TWYb2O4/emRugxiyHZ5JyHW5F+RPnDzfrE=
+google.golang.org/grpc v1.39.1/go.mod h1:PImNr+rS9TWYb2O4/emRugxiyHZ5JyHW5F+RPnDzfrE=
+google.golang.org/grpc v1.40.0 h1:AGJ0Ih4mHjSeibYkFGh1dD9KJ/eOtZ93I6hoHhukQ5Q=
+google.golang.org/grpc v1.40.0/go.mod h1:ogyxbiOoUXAkP+4+xa6PZSE9DZgIHtSpzjDTB9KAK34=
 google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.1.0/go.mod h1:6Kw0yEErY5E/yWrBtf03jp27GLLJujG4z/JK95pnjjw=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
@@ -488,12 +517,14 @@ google.golang.org/protobuf v1.23.1-0.20200526195155-81db48ad09cc/go.mod h1:EGpAD
 google.golang.org/protobuf v1.24.0/go.mod h1:r/3tXBNzIEhYS9I1OUVjXDlt8tc493IdKGjtUeSXeh4=
 google.golang.org/protobuf v1.25.0/go.mod h1:9JNX74DMeImyA3h4bdi1ymwjUzf21/xIlbajtzgsN7c=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
-google.golang.org/protobuf v1.26.0 h1:bxAC2xTBsZGibn2RTntX0oH50xLsqy1OxA9tTL3p/lk=
 google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
+google.golang.org/protobuf v1.27.1 h1:SnqbnDw1V7RiZcXPx5MEeqPv2s79L9i7BJUlG/+RurQ=
+google.golang.org/protobuf v1.27.1/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.3/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.0-20190106161140-3f1c8253044a/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=

vendor/cloud.google.com/go/storage/go110.go

@@ -1,56 +0,0 @@
-// Copyright 2017 Google LLC
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build go1.10
-
-package storage
-
-import (
-	"io"
-	"net/url"
-	"strings"
-
-	"google.golang.org/api/googleapi"
-)
-
-func shouldRetry(err error) bool {
-	if err == io.ErrUnexpectedEOF {
-		return true
-	}
-	switch e := err.(type) {
-	case *googleapi.Error:
-		// Retry on 429 and 5xx, according to
-		// https://cloud.google.com/storage/docs/exponential-backoff.
-		return e.Code == 429 || (e.Code >= 500 && e.Code < 600)
-	case *url.Error:
-		// Retry socket-level errors ECONNREFUSED and ENETUNREACH (from syscall).
-		// Unfortunately the error type is unexported, so we resort to string
-		// matching.
-		retriable := []string{"connection refused", "connection reset"}
-		for _, s := range retriable {
-			if strings.Contains(e.Error(), s) {
-				return true
-			}
-		}
-	case interface{ Temporary() bool }:
-		if e.Temporary() {
-			return true
-		}
-	}
-	// Unwrap is only supported in go1.13.x+
-	if e, ok := err.(interface{ Unwrap() error }); ok {
-		return shouldRetry(e.Unwrap())
-	}
-	return false
-}

vendor/cloud.google.com/go/storage/go_mod_tidy_hack.go

@@ -14,6 +14,7 @@
 
 // This file, and the cloud.google.com/go import, won't actually become part of
 // the resultant binary.
+//go:build modhack
 // +build modhack
 
 package storage

vendor/cloud.google.com/go/storage/internal/apiv2/doc.go

@@ -0,0 +1,140 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Code generated by protoc-gen-go_gapic. DO NOT EDIT.
+
+// Package storage is an auto-generated package for the
+// Cloud Storage API.
+//
+// Lets you store and retrieve potentially-large, immutable data objects.
+//
+//   NOTE: This package is in alpha. It is not stable, and is likely to change.
+//
+// Example usage
+//
+// To get started with this package, create a client.
+//  ctx := context.Background()
+//  c, err := storage.NewClient(ctx)
+//  if err != nil {
+//  	// TODO: Handle error.
+//  }
+//  defer c.Close()
+//
+// The client will use your default application credentials. Clients should be reused instead of created as needed.
+// The methods of Client are safe for concurrent use by multiple goroutines.
+// The returned client must be Closed when it is done being used.
+//
+// Using the Client
+//
+// The following is an example of making an API call with the newly created client.
+//
+// Use of Context
+//
+// The ctx passed to NewClient is used for authentication requests and
+// for creating the underlying connection, but is not used for subsequent calls.
+// Individual methods on the client use the ctx given to them.
+//
+// To close the open connection, use the Close() method.
+//
+// For information about setting deadlines, reusing contexts, and more
+// please visit https://pkg.go.dev/cloud.google.com/go.
+package storage // import "cloud.google.com/go/storage/internal/apiv2"
+
+import (
+	"context"
+	"os"
+	"runtime"
+	"strconv"
+	"strings"
+	"unicode"
+
+	"google.golang.org/api/option"
+	"google.golang.org/grpc/metadata"
+)
+
+// For more information on implementing a client constructor hook, see
+// https://github.com/googleapis/google-cloud-go/wiki/Customizing-constructors.
+type clientHookParams struct{}
+type clientHook func(context.Context, clientHookParams) ([]option.ClientOption, error)
+
+const versionClient = "20210821"
+
+func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {
+	out, _ := metadata.FromOutgoingContext(ctx)
+	out = out.Copy()
+	for _, md := range mds {
+		for k, v := range md {
+			out[k] = append(out[k], v...)
+		}
+	}
+	return metadata.NewOutgoingContext(ctx, out)
+}
+
+func checkDisableDeadlines() (bool, error) {
+	raw, ok := os.LookupEnv("GOOGLE_API_GO_EXPERIMENTAL_DISABLE_DEFAULT_DEADLINE")
+	if !ok {
+		return false, nil
+	}
+
+	b, err := strconv.ParseBool(raw)
+	return b, err
+}
+
+// DefaultAuthScopes reports the default set of authentication scopes to use with this package.
+func DefaultAuthScopes() []string {
+	return []string{
+		"https://www.googleapis.com/auth/cloud-platform",
+		"https://www.googleapis.com/auth/cloud-platform.read-only",
+		"https://www.googleapis.com/auth/devstorage.full_control",
+		"https://www.googleapis.com/auth/devstorage.read_only",
+		"https://www.googleapis.com/auth/devstorage.read_write",
+	}
+}
+
+// versionGo returns the Go runtime version. The returned string
+// has no whitespace, suitable for reporting in header.
+func versionGo() string {
+	const develPrefix = "devel +"
+
+	s := runtime.Version()
+	if strings.HasPrefix(s, develPrefix) {
+		s = s[len(develPrefix):]
+		if p := strings.IndexFunc(s, unicode.IsSpace); p >= 0 {
+			s = s[:p]
+		}
+		return s
+	}
+
+	notSemverRune := func(r rune) bool {
+		return !strings.ContainsRune("0123456789.", r)
+	}
+
+	if strings.HasPrefix(s, "go1") {
+		s = s[2:]
+		var prerelease string
+		if p := strings.IndexFunc(s, notSemverRune); p >= 0 {
+			s, prerelease = s[:p], s[p:]
+		}
+		if strings.HasSuffix(s, ".") {
+			s += "0"
+		} else if strings.Count(s, ".") < 2 {
+			s += ".0"
+		}
+		if prerelease != "" {
+			s += "-" + prerelease
+		}
+		return s
+	}
+	return "UNKNOWN"
+}

vendor/cloud.google.com/go/storage/internal/apiv2/gapic_metadata.json

@@ -0,0 +1,38 @@
+{
+  "schema": "1.0",
+  "comment": "This file maps proto services/RPCs to the corresponding library clients/methods.",
+  "language": "go",
+  "protoPackage": "google.storage.v2",
+  "libraryPackage": "cloud.google.com/go/storage/internal/apiv2",
+  "services": {
+    "Storage": {
+      "clients": {
+        "grpc": {
+          "libraryClient": "Client",
+          "rpcs": {
+            "QueryWriteStatus": {
+              "methods": [
+                "QueryWriteStatus"
+              ]
+            },
+            "ReadObject": {
+              "methods": [
+                "ReadObject"
+              ]
+            },
+            "StartResumableWrite": {
+              "methods": [
+                "StartResumableWrite"
+              ]
+            },
+            "WriteObject": {
+              "methods": [
+                "WriteObject"
+              ]
+            }
+          }
+        }
+      }
+    }
+  }
+}

vendor/cloud.google.com/go/storage/internal/apiv2/storage_client.go

@@ -0,0 +1,359 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Code generated by protoc-gen-go_gapic. DO NOT EDIT.
+
+package storage
+
+import (
+	"context"
+	"math"
+	"time"
+
+	gax "github.com/googleapis/gax-go/v2"
+	"google.golang.org/api/option"
+	"google.golang.org/api/option/internaloption"
+	gtransport "google.golang.org/api/transport/grpc"
+	storagepb "google.golang.org/genproto/googleapis/storage/v2"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/metadata"
+)
+
+var newClientHook clientHook
+
+// CallOptions contains the retry settings for each method of Client.
+type CallOptions struct {
+	ReadObject          []gax.CallOption
+	WriteObject         []gax.CallOption
+	StartResumableWrite []gax.CallOption
+	QueryWriteStatus    []gax.CallOption
+}
+
+func defaultGRPCClientOptions() []option.ClientOption {
+	return []option.ClientOption{
+		internaloption.WithDefaultEndpoint("storage.googleapis.com:443"),
+		internaloption.WithDefaultMTLSEndpoint("storage.mtls.googleapis.com:443"),
+		internaloption.WithDefaultAudience("https://storage.googleapis.com/"),
+		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
+		internaloption.EnableJwtWithScope(),
+		option.WithGRPCDialOption(grpc.WithDisableServiceConfig()),
+		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
+			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
+	}
+}
+
+func defaultCallOptions() *CallOptions {
+	return &CallOptions{
+		ReadObject: []gax.CallOption{
+			gax.WithRetry(func() gax.Retryer {
+				return gax.OnCodes([]codes.Code{
+					codes.DeadlineExceeded,
+					codes.Unavailable,
+				}, gax.Backoff{
+					Initial:    1000 * time.Millisecond,
+					Max:        60000 * time.Millisecond,
+					Multiplier: 2.00,
+				})
+			}),
+		},
+		WriteObject: []gax.CallOption{
+			gax.WithRetry(func() gax.Retryer {
+				return gax.OnCodes([]codes.Code{
+					codes.DeadlineExceeded,
+					codes.Unavailable,
+				}, gax.Backoff{
+					Initial:    1000 * time.Millisecond,
+					Max:        60000 * time.Millisecond,
+					Multiplier: 2.00,
+				})
+			}),
+		},
+		StartResumableWrite: []gax.CallOption{
+			gax.WithRetry(func() gax.Retryer {
+				return gax.OnCodes([]codes.Code{
+					codes.DeadlineExceeded,
+					codes.Unavailable,
+				}, gax.Backoff{
+					Initial:    1000 * time.Millisecond,
+					Max:        60000 * time.Millisecond,
+					Multiplier: 2.00,
+				})
+			}),
+		},
+		QueryWriteStatus: []gax.CallOption{
+			gax.WithRetry(func() gax.Retryer {
+				return gax.OnCodes([]codes.Code{
+					codes.DeadlineExceeded,
+					codes.Unavailable,
+				}, gax.Backoff{
+					Initial:    1000 * time.Millisecond,
+					Max:        60000 * time.Millisecond,
+					Multiplier: 2.00,
+				})
+			}),
+		},
+	}
+}
+
+// internalClient is an interface that defines the methods availaible from Cloud Storage API.
+type internalClient interface {
+	Close() error
+	setGoogleClientInfo(...string)
+	Connection() *grpc.ClientConn
+	ReadObject(context.Context, *storagepb.ReadObjectRequest, ...gax.CallOption) (storagepb.Storage_ReadObjectClient, error)
+	WriteObject(context.Context, ...gax.CallOption) (storagepb.Storage_WriteObjectClient, error)
+	StartResumableWrite(context.Context, *storagepb.StartResumableWriteRequest, ...gax.CallOption) (*storagepb.StartResumableWriteResponse, error)
+	QueryWriteStatus(context.Context, *storagepb.QueryWriteStatusRequest, ...gax.CallOption) (*storagepb.QueryWriteStatusResponse, error)
+}
+
+// Client is a client for interacting with Cloud Storage API.
+// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
+//
+// Manages Google Cloud Storage resources.
+type Client struct {
+	// The internal transport-dependent client.
+	internalClient internalClient
+
+	// The call options for this service.
+	CallOptions *CallOptions
+}
+
+// Wrapper methods routed to the internal client.
+
+// Close closes the connection to the API service. The user should invoke this when
+// the client is no longer required.
+func (c *Client) Close() error {
+	return c.internalClient.Close()
+}
+
+// setGoogleClientInfo sets the name and version of the application in
+// the `x-goog-api-client` header passed on each request. Intended for
+// use by Google-written clients.
+func (c *Client) setGoogleClientInfo(keyval ...string) {
+	c.internalClient.setGoogleClientInfo(keyval...)
+}
+
+// Connection returns a connection to the API service.
+//
+// Deprecated.
+func (c *Client) Connection() *grpc.ClientConn {
+	return c.internalClient.Connection()
+}
+
+// ReadObject reads an object’s data.
+func (c *Client) ReadObject(ctx context.Context, req *storagepb.ReadObjectRequest, opts ...gax.CallOption) (storagepb.Storage_ReadObjectClient, error) {
+	return c.internalClient.ReadObject(ctx, req, opts...)
+}
+
+// WriteObject stores a new object and metadata.
+//
+// An object can be written either in a single message stream or in a
+// resumable sequence of message streams. To write using a single stream,
+// the client should include in the first message of the stream an
+// WriteObjectSpec describing the destination bucket, object, and any
+// preconditions. Additionally, the final message must set ‘finish_write’ to
+// true, or else it is an error.
+//
+// For a resumable write, the client should instead call
+// StartResumableWrite() and provide that method an WriteObjectSpec.
+// They should then attach the returned upload_id to the first message of
+// each following call to Create. If there is an error or the connection is
+// broken during the resumable Create(), the client should check the status
+// of the Create() by calling QueryWriteStatus() and continue writing from
+// the returned committed_size. This may be less than the amount of data the
+// client previously sent.
+//
+// The service will not view the object as complete until the client has
+// sent a WriteObjectRequest with finish_write set to true. Sending any
+// requests on a stream after sending a request with finish_write set to
+// true will cause an error. The client should check the response it
+// receives to determine how much data the service was able to commit and
+// whether the service views the object as complete.
+func (c *Client) WriteObject(ctx context.Context, opts ...gax.CallOption) (storagepb.Storage_WriteObjectClient, error) {
+	return c.internalClient.WriteObject(ctx, opts...)
+}
+
+// StartResumableWrite starts a resumable write. How long the write operation remains valid, and
+// what happens when the write operation becomes invalid, are
+// service-dependent.
+func (c *Client) StartResumableWrite(ctx context.Context, req *storagepb.StartResumableWriteRequest, opts ...gax.CallOption) (*storagepb.StartResumableWriteResponse, error) {
+	return c.internalClient.StartResumableWrite(ctx, req, opts...)
+}
+
+// QueryWriteStatus determines the committed_size for an object that is being written, which
+// can then be used as the write_offset for the next Write() call.
+//
+// If the object does not exist (i.e., the object has been deleted, or the
+// first Write() has not yet reached the service), this method returns the
+// error NOT_FOUND.
+//
+// The client may call QueryWriteStatus() at any time to determine how
+// much data has been processed for this object. This is useful if the
+// client is buffering data and needs to know which data can be safely
+// evicted. For any sequence of QueryWriteStatus() calls for a given
+// object name, the sequence of returned committed_size values will be
+// non-decreasing.
+func (c *Client) QueryWriteStatus(ctx context.Context, req *storagepb.QueryWriteStatusRequest, opts ...gax.CallOption) (*storagepb.QueryWriteStatusResponse, error) {
+	return c.internalClient.QueryWriteStatus(ctx, req, opts...)
+}
+
+// gRPCClient is a client for interacting with Cloud Storage API over gRPC transport.
+//
+// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
+type gRPCClient struct {
+	// Connection pool of gRPC connections to the service.
+	connPool gtransport.ConnPool
+
+	// flag to opt out of default deadlines via GOOGLE_API_GO_EXPERIMENTAL_DISABLE_DEFAULT_DEADLINE
+	disableDeadlines bool
+
+	// Points back to the CallOptions field of the containing Client
+	CallOptions **CallOptions
+
+	// The gRPC API client.
+	client storagepb.StorageClient
+
+	// The x-goog-* metadata to be sent with each request.
+	xGoogMetadata metadata.MD
+}
+
+// NewClient creates a new storage client based on gRPC.
+// The returned client must be Closed when it is done being used to clean up its underlying connections.
+//
+// Manages Google Cloud Storage resources.
+func NewClient(ctx context.Context, opts ...option.ClientOption) (*Client, error) {
+	clientOpts := defaultGRPCClientOptions()
+	if newClientHook != nil {
+		hookOpts, err := newClientHook(ctx, clientHookParams{})
+		if err != nil {
+			return nil, err
+		}
+		clientOpts = append(clientOpts, hookOpts...)
+	}
+
+	disableDeadlines, err := checkDisableDeadlines()
+	if err != nil {
+		return nil, err
+	}
+
+	connPool, err := gtransport.DialPool(ctx, append(clientOpts, opts...)...)
+	if err != nil {
+		return nil, err
+	}
+	client := Client{CallOptions: defaultCallOptions()}
+
+	c := &gRPCClient{
+		connPool:         connPool,
+		disableDeadlines: disableDeadlines,
+		client:           storagepb.NewStorageClient(connPool),
+		CallOptions:      &client.CallOptions,
+	}
+	c.setGoogleClientInfo()
+
+	client.internalClient = c
+
+	return &client, nil
+}
+
+// Connection returns a connection to the API service.
+//
+// Deprecated.
+func (c *gRPCClient) Connection() *grpc.ClientConn {
+	return c.connPool.Conn()
+}
+
+// setGoogleClientInfo sets the name and version of the application in
+// the `x-goog-api-client` header passed on each request. Intended for
+// use by Google-written clients.
+func (c *gRPCClient) setGoogleClientInfo(keyval ...string) {
+	kv := append([]string{"gl-go", versionGo()}, keyval...)
+	kv = append(kv, "gapic", versionClient, "gax", gax.Version, "grpc", grpc.Version)
+	c.xGoogMetadata = metadata.Pairs("x-goog-api-client", gax.XGoogHeader(kv...))
+}
+
+// Close closes the connection to the API service. The user should invoke this when
+// the client is no longer required.
+func (c *gRPCClient) Close() error {
+	return c.connPool.Close()
+}
+
+func (c *gRPCClient) ReadObject(ctx context.Context, req *storagepb.ReadObjectRequest, opts ...gax.CallOption) (storagepb.Storage_ReadObjectClient, error) {
+	ctx = insertMetadata(ctx, c.xGoogMetadata)
+	var resp storagepb.Storage_ReadObjectClient
+	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
+		var err error
+		resp, err = c.client.ReadObject(ctx, req, settings.GRPC...)
+		return err
+	}, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return resp, nil
+}
+
+func (c *gRPCClient) WriteObject(ctx context.Context, opts ...gax.CallOption) (storagepb.Storage_WriteObjectClient, error) {
+	ctx = insertMetadata(ctx, c.xGoogMetadata)
+	var resp storagepb.Storage_WriteObjectClient
+	opts = append((*c.CallOptions).WriteObject[0:len((*c.CallOptions).WriteObject):len((*c.CallOptions).WriteObject)], opts...)
+	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
+		var err error
+		resp, err = c.client.WriteObject(ctx, settings.GRPC...)
+		return err
+	}, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return resp, nil
+}
+
+func (c *gRPCClient) StartResumableWrite(ctx context.Context, req *storagepb.StartResumableWriteRequest, opts ...gax.CallOption) (*storagepb.StartResumableWriteResponse, error) {
+	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
+		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
+		defer cancel()
+		ctx = cctx
+	}
+	ctx = insertMetadata(ctx, c.xGoogMetadata)
+	opts = append((*c.CallOptions).StartResumableWrite[0:len((*c.CallOptions).StartResumableWrite):len((*c.CallOptions).StartResumableWrite)], opts...)
+	var resp *storagepb.StartResumableWriteResponse
+	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
+		var err error
+		resp, err = c.client.StartResumableWrite(ctx, req, settings.GRPC...)
+		return err
+	}, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return resp, nil
+}
+
+func (c *gRPCClient) QueryWriteStatus(ctx context.Context, req *storagepb.QueryWriteStatusRequest, opts ...gax.CallOption) (*storagepb.QueryWriteStatusResponse, error) {
+	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
+		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
+		defer cancel()
+		ctx = cctx
+	}
+	ctx = insertMetadata(ctx, c.xGoogMetadata)
+	opts = append((*c.CallOptions).QueryWriteStatus[0:len((*c.CallOptions).QueryWriteStatus):len((*c.CallOptions).QueryWriteStatus)], opts...)
+	var resp *storagepb.QueryWriteStatusResponse
+	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
+		var err error
+		resp, err = c.client.QueryWriteStatus(ctx, req, settings.GRPC...)
+		return err
+	}, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return resp, nil
+}

vendor/cloud.google.com/go/storage/invoke.go

@@ -16,9 +16,15 @@ package storage
 
 import (
 	"context"
+	"io"
+	"net/url"
+	"strings"
 
 	"cloud.google.com/go/internal"
 	gax "github.com/googleapis/gax-go/v2"
+	"google.golang.org/api/googleapi"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 )
 
 // runWithRetry calls the function until it returns nil or a non-retryable error, or
@@ -35,3 +41,41 @@ func runWithRetry(ctx context.Context, call func() error) error {
 		return true, err
 	})
 }
+
+func shouldRetry(err error) bool {
+	if err == io.ErrUnexpectedEOF {
+		return true
+	}
+	switch e := err.(type) {
+	case *googleapi.Error:
+		// Retry on 429 and 5xx, according to
+		// https://cloud.google.com/storage/docs/exponential-backoff.
+		return e.Code == 429 || (e.Code >= 500 && e.Code < 600)
+	case *url.Error:
+		// Retry socket-level errors ECONNREFUSED and ENETUNREACH (from syscall).
+		// Unfortunately the error type is unexported, so we resort to string
+		// matching.
+		retriable := []string{"connection refused", "connection reset"}
+		for _, s := range retriable {
+			if strings.Contains(e.Error(), s) {
+				return true
+			}
+		}
+	case interface{ Temporary() bool }:
+		if e.Temporary() {
+			return true
+		}
+	}
+	// HTTP 429, 502, 503, and 504 all map to gRPC UNAVAILABLE per
+	// https://grpc.github.io/grpc/core/md_doc_http-grpc-status-mapping.html.
+	//
+	// This is only necessary for the experimental gRPC-based media operations.
+	if st, ok := status.FromError(err); ok && st.Code() == codes.Unavailable {
+		return true
+	}
+	// Unwrap is only supported in go1.13.x+
+	if e, ok := err.(interface{ Unwrap() error }); ok {
+		return shouldRetry(e.Unwrap())
+	}
+	return false
+}

vendor/cloud.google.com/go/storage/not_go110.go

@@ -1,42 +0,0 @@
-// Copyright 2017 Google LLC
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build !go1.10
-
-package storage
-
-import (
-	"net/url"
-	"strings"
-
-	"google.golang.org/api/googleapi"
-)
-
-func shouldRetry(err error) bool {
-	switch e := err.(type) {
-	case *googleapi.Error:
-		// Retry on 429 and 5xx, according to
-		// https://cloud.google.com/storage/docs/exponential-backoff.
-		return e.Code == 429 || (e.Code >= 500 && e.Code < 600)
-	case *url.Error:
-		// Retry on REFUSED_STREAM.
-		// Unfortunately the error type is unexported, so we resort to string
-		// matching.
-		return strings.Contains(e.Error(), "REFUSED_STREAM")
-	case interface{ Temporary() bool }:
-		return e.Temporary()
-	default:
-		return false
-	}
-}

vendor/cloud.google.com/go/storage/reader.go

@@ -29,6 +29,8 @@ import (
 
 	"cloud.google.com/go/internal/trace"
 	"google.golang.org/api/googleapi"
+	storagepb "google.golang.org/genproto/googleapis/storage/v2"
+	"google.golang.org/protobuf/proto"
 )
 
 var crc32cTable = crc32.MakeTable(crc32.Castagnoli)
@@ -94,6 +96,10 @@ func (o *ObjectHandle) NewRangeReader(ctx context.Context, offset, length int64)
 	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.Object.NewRangeReader")
 	defer func() { trace.EndSpan(ctx, err) }()
 
+	if o.c.gc != nil {
+		return o.newRangeReaderWithGRPC(ctx, offset, length)
+	}
+
 	if err := o.validate(); err != nil {
 		return nil, err
 	}
@@ -149,7 +155,14 @@ func (o *ObjectHandle) NewRangeReader(ctx context.Context, offset, length int64)
 			req.Header.Set("Range", fmt.Sprintf("bytes=%d-%d", start, offset+length-1))
 		}
 		// We wait to assign conditions here because the generation number can change in between reopen() runs.
-		req.URL.RawQuery = conditionsQuery(gen, o.conds)
+		if err := setConditionsHeaders(req.Header, o.conds); err != nil {
+			return nil, err
+		}
+		// If an object generation is specified, include generation as query string parameters.
+		if gen >= 0 {
+			req.URL.RawQuery = fmt.Sprintf("generation=%d", gen)
+		}
+
 		var res *http.Response
 		err = runWithRetry(ctx, func() error {
 			res, err = o.c.hc.Do(req)
@@ -220,6 +233,8 @@ func (o *ObjectHandle) NewRangeReader(ctx context.Context, offset, length int64)
 		if !strings.HasPrefix(cr, "bytes ") || !strings.Contains(cr, "/") {
 			return nil, fmt.Errorf("storage: invalid Content-Range %q", cr)
 		}
+		// Content range is formatted <first byte>-<last byte>/<total size>. We take
+		// the total size.
 		size, err = strconv.ParseInt(cr[strings.LastIndex(cr, "/")+1:], 10, 64)
 		if err != nil {
 			return nil, fmt.Errorf("storage: invalid Content-Range %q", cr)
@@ -324,6 +339,24 @@ func parseCRC32c(res *http.Response) (uint32, bool) {
 	return 0, false
 }
 
+// setConditionsHeaders sets precondition request headers for downloads
+// using the XML API. It assumes that the conditions have been validated.
+func setConditionsHeaders(headers http.Header, conds *Conditions) error {
+	if conds == nil {
+		return nil
+	}
+	if conds.MetagenerationMatch != 0 {
+		headers.Set("x-goog-if-metageneration-match", fmt.Sprint(conds.MetagenerationMatch))
+	}
+	switch {
+	case conds.GenerationMatch != 0:
+		headers.Set("x-goog-if-generation-match", fmt.Sprint(conds.GenerationMatch))
+	case conds.DoesNotExist:
+		headers.Set("x-goog-if-generation-match", "0")
+	}
+	return nil
+}
+
 var emptyBody = ioutil.NopCloser(strings.NewReader(""))
 
 // Reader reads a Cloud Storage object.
@@ -340,15 +373,36 @@ type Reader struct {
 	wantCRC            uint32 // the CRC32c value the server sent in the header
 	gotCRC             uint32 // running crc
 	reopen             func(seen int64) (*http.Response, error)
+
+	// The following fields are only for use in the gRPC hybrid client.
+	stream         storagepb.Storage_ReadObjectClient
+	reopenWithGRPC func(seen int64) (*readStreamResponse, context.CancelFunc, error)
+	leftovers      []byte
+	cancelStream   context.CancelFunc
+}
+
+type readStreamResponse struct {
+	stream   storagepb.Storage_ReadObjectClient
+	response *storagepb.ReadObjectResponse
 }
 
 // Close closes the Reader. It must be called when done reading.
 func (r *Reader) Close() error {
-	return r.body.Close()
+	if r.body != nil {
+		return r.body.Close()
+	}
+
+	r.closeStream()
+	return nil
 }
 
 func (r *Reader) Read(p []byte) (int, error) {
-	n, err := r.readWithRetry(p)
+	read := r.readWithRetry
+	if r.reopenWithGRPC != nil {
+		read = r.readWithGRPC
+	}
+
+	n, err := read(p)
 	if r.remain != -1 {
 		r.remain -= int64(n)
 	}
@@ -367,6 +421,136 @@ func (r *Reader) Read(p []byte) (int, error) {
 	return n, err
 }
 
+// newRangeReaderWithGRPC creates a new Reader with the given range that uses
+// gRPC to read Object content.
+//
+// This is an experimental API and not intended for public use.
+func (o *ObjectHandle) newRangeReaderWithGRPC(ctx context.Context, offset, length int64) (r *Reader, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.Object.newRangeReaderWithGRPC")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	if o.c.gc == nil {
+		err = fmt.Errorf("handle doesn't have a gRPC client initialized")
+		return
+	}
+	if err = o.validate(); err != nil {
+		return
+	}
+
+	// A negative length means "read to the end of the object", but the
+	// read_limit field it corresponds to uses zero to mean the same thing. Thus
+	// we coerce the length to 0 to read to the end of the object.
+	if length < 0 {
+		length = 0
+	}
+
+	// For now, there are only globally unique buckets, and "_" is the alias
+	// project ID for such buckets.
+	b := bucketResourceName("_", o.bucket)
+	req := &storagepb.ReadObjectRequest{
+		Bucket: b,
+		Object: o.object,
+	}
+	// The default is a negative value, which means latest.
+	if o.gen >= 0 {
+		req.Generation = o.gen
+	}
+
+	// Define a function that initiates a Read with offset and length, assuming
+	// we have already read seen bytes.
+	reopen := func(seen int64) (*readStreamResponse, context.CancelFunc, error) {
+		// If the context has already expired, return immediately without making
+		// we call.
+		if err := ctx.Err(); err != nil {
+			return nil, nil, err
+		}
+
+		cc, cancel := context.WithCancel(ctx)
+
+		start := offset + seen
+		// Only set a ReadLimit if length is greater than zero, because zero
+		// means read it all.
+		if length > 0 {
+			req.ReadLimit = length - seen
+		}
+		req.ReadOffset = start
+
+		setRequestConditions(req, o.conds)
+
+		var stream storagepb.Storage_ReadObjectClient
+		var msg *storagepb.ReadObjectResponse
+		var err error
+
+		err = runWithRetry(cc, func() error {
+			stream, err = o.c.gc.ReadObject(cc, req)
+			if err != nil {
+				return err
+			}
+
+			msg, err = stream.Recv()
+
+			return err
+		})
+		if err != nil {
+			// Close the stream context we just created to ensure we don't leak
+			// resources.
+			cancel()
+			return nil, nil, err
+		}
+
+		return &readStreamResponse{stream, msg}, cancel, nil
+	}
+
+	res, cancel, err := reopen(0)
+	if err != nil {
+		return nil, err
+	}
+
+	r = &Reader{
+		stream:         res.stream,
+		reopenWithGRPC: reopen,
+		cancelStream:   cancel,
+	}
+
+	// The first message was Recv'd on stream open, use it to populate the
+	// object metadata.
+	msg := res.response
+	obj := msg.GetMetadata()
+	// This is the size of the entire object, even if only a range was requested.
+	size := obj.GetSize()
+
+	r.Attrs = ReaderObjectAttrs{
+		Size:            size,
+		ContentType:     obj.GetContentType(),
+		ContentEncoding: obj.GetContentEncoding(),
+		CacheControl:    obj.GetCacheControl(),
+		LastModified:    obj.GetUpdateTime().AsTime(),
+		Metageneration:  obj.GetMetageneration(),
+		Generation:      obj.GetGeneration(),
+	}
+
+	r.size = size
+	cr := msg.GetContentRange()
+	if cr != nil {
+		r.Attrs.StartOffset = cr.GetStart()
+		r.remain = cr.GetEnd() - cr.GetStart() + 1
+	} else {
+		r.remain = size
+	}
+
+	// Only support checksums when reading an entire object, not a range.
+	if msg.GetObjectChecksums().Crc32C != nil && offset == 0 && length == 0 {
+		r.wantCRC = msg.GetObjectChecksums().GetCrc32C()
+		r.checkCRC = true
+	}
+
+	// Store the content from the first Recv in the client buffer for reading
+	// later.
+	r.leftovers = msg.GetChecksummedData().GetContent()
+
+	return r, nil
+}
+
 func (r *Reader) readWithRetry(p []byte) (int, error) {
 	n := 0
 	for len(p[n:]) > 0 {
@@ -390,6 +574,138 @@ func (r *Reader) readWithRetry(p []byte) (int, error) {
 	return n, nil
 }
 
+// closeStream cancels a stream's context in order for it to be closed and
+// collected.
+//
+// This is an experimental API and not intended for public use.
+func (r *Reader) closeStream() {
+	if r.cancelStream != nil {
+		r.cancelStream()
+	}
+	r.stream = nil
+}
+
+// readWithGRPC reads bytes into the user's buffer from an open gRPC stream.
+//
+// This is an experimental API and not intended for public use.
+func (r *Reader) readWithGRPC(p []byte) (int, error) {
+	// No stream to read from, either never initiliazed or Close was called.
+	// Note: There is a potential concurrency issue if multiple routines are
+	// using the same reader. One encounters an error and the stream is closed
+	// and then reopened while the other routine attempts to read from it.
+	if r.stream == nil {
+		return 0, fmt.Errorf("reader has been closed")
+	}
+
+	// The entire object has been read by this reader, return EOF.
+	if r.size != 0 && r.size == r.seen {
+		return 0, io.EOF
+	}
+
+	var n int
+	// Read leftovers and return what was available to conform to the Reader
+	// interface: https://pkg.go.dev/io#Reader.
+	if len(r.leftovers) > 0 {
+		n = copy(p, r.leftovers)
+		r.seen += int64(n)
+		r.leftovers = r.leftovers[n:]
+		return n, nil
+	}
+
+	// Attempt to Recv the next message on the stream.
+	msg, err := r.recv()
+	if err != nil {
+		return 0, err
+	}
+
+	// TODO: Determine if we need to capture incremental CRC32C for this
+	// chunk. The Object CRC32C checksum is captured when directed to read
+	// the entire Object. If directed to read a range, we may need to
+	// calculate the range's checksum for verification if the checksum is
+	// present in the response here.
+	// TODO: Figure out if we need to support decompressive transcoding
+	// https://cloud.google.com/storage/docs/transcoding.
+	content := msg.GetChecksummedData().GetContent()
+	n = copy(p[n:], content)
+	leftover := len(content) - n
+	if leftover > 0 {
+		// Wasn't able to copy all of the data in the message, store for
+		// future Read calls.
+		// TODO: Instead of acquiring a new block of memory, should we reuse
+		// the existing leftovers slice, expanding it if necessary?
+		r.leftovers = make([]byte, leftover)
+		copy(r.leftovers, content[n:])
+	}
+	r.seen += int64(n)
+
+	return n, nil
+}
+
+// recv attempts to Recv the next message on the stream. In the event
+// that a retryable error is encountered, the stream will be closed, reopened,
+// and Recv again. This will attempt to Recv until one of the following is true:
+//
+// * Recv is successful
+// * A non-retryable error is encountered
+// * The Reader's context is canceled
+//
+// The last error received is the one that is returned, which could be from
+// an attempt to reopen the stream.
+//
+// This is an experimental API and not intended for public use.
+func (r *Reader) recv() (*storagepb.ReadObjectResponse, error) {
+	msg, err := r.stream.Recv()
+	if err != nil && shouldRetry(err) {
+		// This will "close" the existing stream and immediately attempt to
+		// reopen the stream, but will backoff if further attempts are necessary.
+		// Reopening the stream Recvs the first message, so if retrying is
+		// successful, the next logical chunk will be returned.
+		msg, err = r.reopenStream(r.seen)
+	}
+
+	return msg, err
+}
+
+// reopenStream "closes" the existing stream and attempts to reopen a stream and
+// sets the Reader's stream and cancelStream properties in the process.
+//
+// This is an experimental API and not intended for public use.
+func (r *Reader) reopenStream(seen int64) (*storagepb.ReadObjectResponse, error) {
+	// Close existing stream and initialize new stream with updated offset.
+	r.closeStream()
+
+	res, cancel, err := r.reopenWithGRPC(r.seen)
+	if err != nil {
+		return nil, err
+	}
+	r.stream = res.stream
+	r.cancelStream = cancel
+	return res.response, nil
+}
+
+// setRequestConditions is used to apply the given Conditions to a gRPC request
+// message.
+//
+// This is an experimental API and not intended for public use.
+func setRequestConditions(req *storagepb.ReadObjectRequest, conds *Conditions) {
+	if conds == nil {
+		return
+	}
+	if conds.MetagenerationMatch != 0 {
+		req.IfMetagenerationMatch = proto.Int64(conds.MetagenerationMatch)
+	} else if conds.MetagenerationNotMatch != 0 {
+		req.IfMetagenerationNotMatch = proto.Int64(conds.MetagenerationNotMatch)
+	}
+	switch {
+	case conds.GenerationNotMatch != 0:
+		req.IfGenerationNotMatch = proto.Int64(conds.GenerationNotMatch)
+	case conds.GenerationMatch != 0:
+		req.IfGenerationMatch = proto.Int64(conds.GenerationMatch)
+	case conds.DoesNotExist:
+		req.IfGenerationMatch = proto.Int64(0)
+	}
+}
+
 // Size returns the size of the object in bytes.
 // The returned value is always the same and is not affected by
 // calls to Read or Close.

vendor/cloud.google.com/go/storage/storage.go

@@ -33,7 +33,6 @@ import (
 	"reflect"
 	"regexp"
 	"sort"
-	"strconv"
 	"strings"
 	"time"
 	"unicode/utf8"
@@ -41,11 +40,15 @@ import (
 	"cloud.google.com/go/internal/optional"
 	"cloud.google.com/go/internal/trace"
 	"cloud.google.com/go/internal/version"
+	gapic "cloud.google.com/go/storage/internal/apiv2"
 	"google.golang.org/api/googleapi"
 	"google.golang.org/api/option"
 	"google.golang.org/api/option/internaloption"
 	raw "google.golang.org/api/storage/v1"
 	htransport "google.golang.org/api/transport/http"
+	storagepb "google.golang.org/genproto/googleapis/storage/v2"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/types/known/timestamppb"
 )
 
 // Methods which can be used in signed URLs.
@@ -91,10 +94,13 @@ type Client struct {
 	raw *raw.Service
 	// Scheme describes the scheme under the current host.
 	scheme string
-	// EnvHost is the host set on the STORAGE_EMULATOR_HOST variable.
-	envHost string
 	// ReadHost is the default host used on the reader.
 	readHost string
+
+	// gc is an optional gRPC-based, GAPIC client.
+	//
+	// This is an experimental field and not intended for public use.
+	gc *gapic.Client
 }
 
 // NewClient creates a new Google Cloud Storage client.
@@ -104,7 +110,6 @@ type Client struct {
 // Clients should be reused instead of created as needed. The methods of Client
 // are safe for concurrent use by multiple goroutines.
 func NewClient(ctx context.Context, opts ...option.ClientOption) (*Client, error) {
-	var host, readHost, scheme string
 
 	// In general, it is recommended to use raw.NewService instead of htransport.NewClient
 	// since raw.NewService configures the correct default endpoints when initializing the
@@ -113,23 +118,35 @@ func NewClient(ctx context.Context, opts ...option.ClientOption) (*Client, error
 	// here so it can be re-used by both reader.go and raw.NewService. This means we need to
 	// manually configure the default endpoint options on the http client. Furthermore, we
 	// need to account for STORAGE_EMULATOR_HOST override when setting the default endpoints.
-	if host = os.Getenv("STORAGE_EMULATOR_HOST"); host == "" {
+	if host := os.Getenv("STORAGE_EMULATOR_HOST"); host == "" {
-		scheme = "https"
-		readHost = "storage.googleapis.com"
-
 		// Prepend default options to avoid overriding options passed by the user.
 		opts = append([]option.ClientOption{option.WithScopes(ScopeFullControl), option.WithUserAgent(userAgent)}, opts...)
 
 		opts = append(opts, internaloption.WithDefaultEndpoint("https://storage.googleapis.com/storage/v1/"))
 		opts = append(opts, internaloption.WithDefaultMTLSEndpoint("https://storage.mtls.googleapis.com/storage/v1/"))
 	} else {
-		scheme = "http"
+		var hostURL *url.URL
-		readHost = host
 
+		if strings.Contains(host, "://") {
+			h, err := url.Parse(host)
+			if err != nil {
+				return nil, err
+			}
+			hostURL = h
+		} else {
+			// Add scheme for user if not supplied in STORAGE_EMULATOR_HOST
+			// URL is only parsed correctly if it has a scheme, so we build it ourselves
+			hostURL = &url.URL{Scheme: "http", Host: host}
+		}
+
+		hostURL.Path = "storage/v1/"
+		endpoint := hostURL.String()
+
+		// Append the emulator host as default endpoint for the user
 		opts = append([]option.ClientOption{option.WithoutAuthentication()}, opts...)
 
-		opts = append(opts, internaloption.WithDefaultEndpoint(host))
+		opts = append(opts, internaloption.WithDefaultEndpoint(endpoint))
-		opts = append(opts, internaloption.WithDefaultMTLSEndpoint(host))
+		opts = append(opts, internaloption.WithDefaultMTLSEndpoint(endpoint))
 	}
 
 	// htransport selects the correct endpoint among WithEndpoint (user override), WithDefaultEndpoint, and WithDefaultMTLSEndpoint.
@@ -142,22 +159,48 @@ func NewClient(ctx context.Context, opts ...option.ClientOption) (*Client, error
 	if err != nil {
 		return nil, fmt.Errorf("storage client: %v", err)
 	}
-	// Update readHost with the chosen endpoint.
+	// Update readHost and scheme with the chosen endpoint.
 	u, err := url.Parse(ep)
 	if err != nil {
 		return nil, fmt.Errorf("supplied endpoint %q is not valid: %v", ep, err)
 	}
-	readHost = u.Host
 
 	return &Client{
 		hc:       hc,
 		raw:      rawService,
-		scheme:   scheme,
+		scheme:   u.Scheme,
-		envHost:  host,
+		readHost: u.Host,
-		readHost: readHost,
 	}, nil
 }
 
+// hybridClientOptions carries the set of client options for HTTP and gRPC clients.
+type hybridClientOptions struct {
+	HTTPOpts []option.ClientOption
+	GRPCOpts []option.ClientOption
+}
+
+// newHybridClient creates a new Storage client that initializes a gRPC-based client
+// for media upload and download operations.
+//
+// This is an experimental API and not intended for public use.
+func newHybridClient(ctx context.Context, opts *hybridClientOptions) (*Client, error) {
+	if opts == nil {
+		opts = &hybridClientOptions{}
+	}
+	c, err := NewClient(ctx, opts.HTTPOpts...)
+	if err != nil {
+		return nil, err
+	}
+
+	g, err := gapic.NewClient(ctx, opts.GRPCOpts...)
+	if err != nil {
+		return nil, err
+	}
+	c.gc = g
+
+	return c, nil
+}
+
 // Close closes the Client.
 //
 // Close need not be called at program exit.
@@ -165,6 +208,9 @@ func (c *Client) Close() error {
 	// Set fields to nil so that subsequent uses will panic.
 	c.hc = nil
 	c.raw = nil
+	if c.gc != nil {
+		return c.gc.Close()
+	}
 	return nil
 }
 
@@ -1089,6 +1135,42 @@ func (o *ObjectAttrs) toRawObject(bucket string) *raw.Object {
 	}
 }
 
+// toProtoObject copies the editable attributes from o to the proto library's Object type.
+func (o *ObjectAttrs) toProtoObject(b string) *storagepb.Object {
+	checksums := &storagepb.ObjectChecksums{Md5Hash: o.MD5}
+	if o.CRC32C > 0 {
+		checksums.Crc32C = proto.Uint32(o.CRC32C)
+	}
+
+	// For now, there are only globally unique buckets, and "_" is the alias
+	// project ID for such buckets.
+	b = bucketResourceName("_", b)
+
+	return &storagepb.Object{
+		Bucket:              b,
+		Name:                o.Name,
+		EventBasedHold:      proto.Bool(o.EventBasedHold),
+		TemporaryHold:       o.TemporaryHold,
+		ContentType:         o.ContentType,
+		ContentEncoding:     o.ContentEncoding,
+		ContentLanguage:     o.ContentLanguage,
+		CacheControl:        o.CacheControl,
+		ContentDisposition:  o.ContentDisposition,
+		StorageClass:        o.StorageClass,
+		Acl:                 toProtoObjectACL(o.ACL),
+		Metadata:            o.Metadata,
+		CreateTime:          toProtoTimestamp(o.Created),
+		CustomTime:          toProtoTimestamp(o.CustomTime),
+		DeleteTime:          toProtoTimestamp(o.Deleted),
+		RetentionExpireTime: toProtoTimestamp(o.RetentionExpirationTime),
+		UpdateTime:          toProtoTimestamp(o.Updated),
+		KmsKey:              o.KMSKeyName,
+		Generation:          o.Generation,
+		Size:                o.Size,
+		Checksums:           checksums,
+	}
+}
+
 // ObjectAttrs represents the metadata for a Google Cloud Storage (GCS) object.
 type ObjectAttrs struct {
 	// Bucket is the name of the bucket containing this GCS object.
@@ -1245,6 +1327,22 @@ func convertTime(t string) time.Time {
 	return r
 }
 
+func convertProtoTime(t *timestamppb.Timestamp) time.Time {
+	var r time.Time
+	if t != nil {
+		r = t.AsTime()
+	}
+	return r
+}
+
+func toProtoTimestamp(t time.Time) *timestamppb.Timestamp {
+	if t.IsZero() {
+		return nil
+	}
+
+	return timestamppb.New(t)
+}
+
 func newObject(o *raw.Object) *ObjectAttrs {
 	if o == nil {
 		return nil
@@ -1290,6 +1388,40 @@ func newObject(o *raw.Object) *ObjectAttrs {
 	}
 }
 
+func newObjectFromProto(r *storagepb.WriteObjectResponse) *ObjectAttrs {
+	o := r.GetResource()
+	if r == nil || o == nil {
+		return nil
+	}
+	return &ObjectAttrs{
+		Bucket:                  parseBucketName(o.Bucket),
+		Name:                    o.Name,
+		ContentType:             o.ContentType,
+		ContentLanguage:         o.ContentLanguage,
+		CacheControl:            o.CacheControl,
+		EventBasedHold:          o.GetEventBasedHold(),
+		TemporaryHold:           o.TemporaryHold,
+		RetentionExpirationTime: convertProtoTime(o.GetRetentionExpireTime()),
+		ACL:                     fromProtoToObjectACLRules(o.GetAcl()),
+		Owner:                   o.GetOwner().GetEntity(),
+		ContentEncoding:         o.ContentEncoding,
+		ContentDisposition:      o.ContentDisposition,
+		Size:                    int64(o.Size),
+		MD5:                     o.GetChecksums().GetMd5Hash(),
+		CRC32C:                  o.GetChecksums().GetCrc32C(),
+		Metadata:                o.Metadata,
+		Generation:              o.Generation,
+		Metageneration:          o.Metageneration,
+		StorageClass:            o.StorageClass,
+		CustomerKeySHA256:       o.GetCustomerEncryption().GetKeySha256(),
+		KMSKeyName:              o.GetKmsKey(),
+		Created:                 convertProtoTime(o.GetCreateTime()),
+		Deleted:                 convertProtoTime(o.GetDeleteTime()),
+		Updated:                 convertProtoTime(o.GetUpdateTime()),
+		CustomTime:              convertProtoTime(o.GetCustomTime()),
+	}
+}
+
 // Decode a uint32 encoded in Base64 in big-endian byte order.
 func decodeUint32(b64 string) (uint32, error) {
 	d, err := base64.StdEncoding.DecodeString(b64)
@@ -1596,44 +1728,6 @@ func setConditionField(call reflect.Value, name string, value interface{}) bool
 	return true
 }
 
-// conditionsQuery returns the generation and conditions as a URL query
-// string suitable for URL.RawQuery.  It assumes that the conditions
-// have been validated.
-func conditionsQuery(gen int64, conds *Conditions) string {
-	// URL escapes are elided because integer strings are URL-safe.
-	var buf []byte
-
-	appendParam := func(s string, n int64) {
-		if len(buf) > 0 {
-			buf = append(buf, '&')
-		}
-		buf = append(buf, s...)
-		buf = strconv.AppendInt(buf, n, 10)
-	}
-
-	if gen >= 0 {
-		appendParam("generation=", gen)
-	}
-	if conds == nil {
-		return string(buf)
-	}
-	switch {
-	case conds.GenerationMatch != 0:
-		appendParam("ifGenerationMatch=", conds.GenerationMatch)
-	case conds.GenerationNotMatch != 0:
-		appendParam("ifGenerationNotMatch=", conds.GenerationNotMatch)
-	case conds.DoesNotExist:
-		appendParam("ifGenerationMatch=", 0)
-	}
-	switch {
-	case conds.MetagenerationMatch != 0:
-		appendParam("ifMetagenerationMatch=", conds.MetagenerationMatch)
-	case conds.MetagenerationNotMatch != 0:
-		appendParam("ifMetagenerationNotMatch=", conds.MetagenerationNotMatch)
-	}
-	return string(buf)
-}
-
 // composeSourceObj wraps a *raw.ComposeRequestSourceObjects, but adds the methods
 // that modifyCall searches for by name.
 type composeSourceObj struct {
@@ -1681,3 +1775,16 @@ func (c *Client) ServiceAccount(ctx context.Context, projectID string) (string,
 	}
 	return res.EmailAddress, nil
 }
+
+// bucketResourceName formats the given project ID and bucketResourceName ID
+// into a Bucket resource name. This is the format necessary for the gRPC API as
+// it conforms to the Resource-oriented design practices in https://google.aip.dev/121.
+func bucketResourceName(p, b string) string {
+	return fmt.Sprintf("projects/%s/buckets/%s", p, b)
+}
+
+// parseBucketName strips the leading resource path segment and returns the
+// bucket ID, which is the simple Bucket name typical of the v1 API.
+func parseBucketName(b string) string {
+	return strings.TrimPrefix(b, "projects/_/buckets/")
+}

vendor/cloud.google.com/go/storage/writer.go

@@ -125,9 +125,6 @@ func (w *Writer) open() error {
 		if w.MD5 != nil {
 			rawObj.Md5Hash = base64.StdEncoding.EncodeToString(w.MD5)
 		}
-		if w.o.c.envHost != "" {
-			w.o.c.raw.BasePath = fmt.Sprintf("%s://%s", w.o.c.scheme, w.o.c.envHost)
-		}
 		call := w.o.c.raw.Objects.Insert(w.o.bucket, rawObj).
 			Media(pr, mediaOpts...).
 			Projection("full").

vendor/github.com/google/go-cmp/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2017 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/google/go-cmp/cmp/compare.go

@@ -0,0 +1,682 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package cmp determines equality of values.
+//
+// This package is intended to be a more powerful and safer alternative to
+// reflect.DeepEqual for comparing whether two values are semantically equal.
+// It is intended to only be used in tests, as performance is not a goal and
+// it may panic if it cannot compare the values. Its propensity towards
+// panicking means that its unsuitable for production environments where a
+// spurious panic may be fatal.
+//
+// The primary features of cmp are:
+//
+// • When the default behavior of equality does not suit the needs of the test,
+// custom equality functions can override the equality operation.
+// For example, an equality function may report floats as equal so long as they
+// are within some tolerance of each other.
+//
+// • Types that have an Equal method may use that method to determine equality.
+// This allows package authors to determine the equality operation for the types
+// that they define.
+//
+// • If no custom equality functions are used and no Equal method is defined,
+// equality is determined by recursively comparing the primitive kinds on both
+// values, much like reflect.DeepEqual. Unlike reflect.DeepEqual, unexported
+// fields are not compared by default; they result in panics unless suppressed
+// by using an Ignore option (see cmpopts.IgnoreUnexported) or explicitly
+// compared using the Exporter option.
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+
+	"github.com/google/go-cmp/cmp/internal/diff"
+	"github.com/google/go-cmp/cmp/internal/flags"
+	"github.com/google/go-cmp/cmp/internal/function"
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+// Equal reports whether x and y are equal by recursively applying the
+// following rules in the given order to x and y and all of their sub-values:
+//
+// • Let S be the set of all Ignore, Transformer, and Comparer options that
+// remain after applying all path filters, value filters, and type filters.
+// If at least one Ignore exists in S, then the comparison is ignored.
+// If the number of Transformer and Comparer options in S is greater than one,
+// then Equal panics because it is ambiguous which option to use.
+// If S contains a single Transformer, then use that to transform the current
+// values and recursively call Equal on the output values.
+// If S contains a single Comparer, then use that to compare the current values.
+// Otherwise, evaluation proceeds to the next rule.
+//
+// • If the values have an Equal method of the form "(T) Equal(T) bool" or
+// "(T) Equal(I) bool" where T is assignable to I, then use the result of
+// x.Equal(y) even if x or y is nil. Otherwise, no such method exists and
+// evaluation proceeds to the next rule.
+//
+// • Lastly, try to compare x and y based on their basic kinds.
+// Simple kinds like booleans, integers, floats, complex numbers, strings, and
+// channels are compared using the equivalent of the == operator in Go.
+// Functions are only equal if they are both nil, otherwise they are unequal.
+//
+// Structs are equal if recursively calling Equal on all fields report equal.
+// If a struct contains unexported fields, Equal panics unless an Ignore option
+// (e.g., cmpopts.IgnoreUnexported) ignores that field or the Exporter option
+// explicitly permits comparing the unexported field.
+//
+// Slices are equal if they are both nil or both non-nil, where recursively
+// calling Equal on all non-ignored slice or array elements report equal.
+// Empty non-nil slices and nil slices are not equal; to equate empty slices,
+// consider using cmpopts.EquateEmpty.
+//
+// Maps are equal if they are both nil or both non-nil, where recursively
+// calling Equal on all non-ignored map entries report equal.
+// Map keys are equal according to the == operator.
+// To use custom comparisons for map keys, consider using cmpopts.SortMaps.
+// Empty non-nil maps and nil maps are not equal; to equate empty maps,
+// consider using cmpopts.EquateEmpty.
+//
+// Pointers and interfaces are equal if they are both nil or both non-nil,
+// where they have the same underlying concrete type and recursively
+// calling Equal on the underlying values reports equal.
+//
+// Before recursing into a pointer, slice element, or map, the current path
+// is checked to detect whether the address has already been visited.
+// If there is a cycle, then the pointed at values are considered equal
+// only if both addresses were previously visited in the same path step.
+func Equal(x, y interface{}, opts ...Option) bool {
+	s := newState(opts)
+	s.compareAny(rootStep(x, y))
+	return s.result.Equal()
+}
+
+// Diff returns a human-readable report of the differences between two values:
+// y - x. It returns an empty string if and only if Equal returns true for the
+// same input values and options.
+//
+// The output is displayed as a literal in pseudo-Go syntax.
+// At the start of each line, a "-" prefix indicates an element removed from x,
+// a "+" prefix to indicates an element added from y, and the lack of a prefix
+// indicates an element common to both x and y. If possible, the output
+// uses fmt.Stringer.String or error.Error methods to produce more humanly
+// readable outputs. In such cases, the string is prefixed with either an
+// 's' or 'e' character, respectively, to indicate that the method was called.
+//
+// Do not depend on this output being stable. If you need the ability to
+// programmatically interpret the difference, consider using a custom Reporter.
+func Diff(x, y interface{}, opts ...Option) string {
+	s := newState(opts)
+
+	// Optimization: If there are no other reporters, we can optimize for the
+	// common case where the result is equal (and thus no reported difference).
+	// This avoids the expensive construction of a difference tree.
+	if len(s.reporters) == 0 {
+		s.compareAny(rootStep(x, y))
+		if s.result.Equal() {
+			return ""
+		}
+		s.result = diff.Result{} // Reset results
+	}
+
+	r := new(defaultReporter)
+	s.reporters = append(s.reporters, reporter{r})
+	s.compareAny(rootStep(x, y))
+	d := r.String()
+	if (d == "") != s.result.Equal() {
+		panic("inconsistent difference and equality results")
+	}
+	return d
+}
+
+// rootStep constructs the first path step. If x and y have differing types,
+// then they are stored within an empty interface type.
+func rootStep(x, y interface{}) PathStep {
+	vx := reflect.ValueOf(x)
+	vy := reflect.ValueOf(y)
+
+	// If the inputs are different types, auto-wrap them in an empty interface
+	// so that they have the same parent type.
+	var t reflect.Type
+	if !vx.IsValid() || !vy.IsValid() || vx.Type() != vy.Type() {
+		t = reflect.TypeOf((*interface{})(nil)).Elem()
+		if vx.IsValid() {
+			vvx := reflect.New(t).Elem()
+			vvx.Set(vx)
+			vx = vvx
+		}
+		if vy.IsValid() {
+			vvy := reflect.New(t).Elem()
+			vvy.Set(vy)
+			vy = vvy
+		}
+	} else {
+		t = vx.Type()
+	}
+
+	return &pathStep{t, vx, vy}
+}
+
+type state struct {
+	// These fields represent the "comparison state".
+	// Calling statelessCompare must not result in observable changes to these.
+	result    diff.Result // The current result of comparison
+	curPath   Path        // The current path in the value tree
+	curPtrs   pointerPath // The current set of visited pointers
+	reporters []reporter  // Optional reporters
+
+	// recChecker checks for infinite cycles applying the same set of
+	// transformers upon the output of itself.
+	recChecker recChecker
+
+	// dynChecker triggers pseudo-random checks for option correctness.
+	// It is safe for statelessCompare to mutate this value.
+	dynChecker dynChecker
+
+	// These fields, once set by processOption, will not change.
+	exporters []exporter // List of exporters for structs with unexported fields
+	opts      Options    // List of all fundamental and filter options
+}
+
+func newState(opts []Option) *state {
+	// Always ensure a validator option exists to validate the inputs.
+	s := &state{opts: Options{validator{}}}
+	s.curPtrs.Init()
+	s.processOption(Options(opts))
+	return s
+}
+
+func (s *state) processOption(opt Option) {
+	switch opt := opt.(type) {
+	case nil:
+	case Options:
+		for _, o := range opt {
+			s.processOption(o)
+		}
+	case coreOption:
+		type filtered interface {
+			isFiltered() bool
+		}
+		if fopt, ok := opt.(filtered); ok && !fopt.isFiltered() {
+			panic(fmt.Sprintf("cannot use an unfiltered option: %v", opt))
+		}
+		s.opts = append(s.opts, opt)
+	case exporter:
+		s.exporters = append(s.exporters, opt)
+	case reporter:
+		s.reporters = append(s.reporters, opt)
+	default:
+		panic(fmt.Sprintf("unknown option %T", opt))
+	}
+}
+
+// statelessCompare compares two values and returns the result.
+// This function is stateless in that it does not alter the current result,
+// or output to any registered reporters.
+func (s *state) statelessCompare(step PathStep) diff.Result {
+	// We do not save and restore curPath and curPtrs because all of the
+	// compareX methods should properly push and pop from them.
+	// It is an implementation bug if the contents of the paths differ from
+	// when calling this function to when returning from it.
+
+	oldResult, oldReporters := s.result, s.reporters
+	s.result = diff.Result{} // Reset result
+	s.reporters = nil        // Remove reporters to avoid spurious printouts
+	s.compareAny(step)
+	res := s.result
+	s.result, s.reporters = oldResult, oldReporters
+	return res
+}
+
+func (s *state) compareAny(step PathStep) {
+	// Update the path stack.
+	s.curPath.push(step)
+	defer s.curPath.pop()
+	for _, r := range s.reporters {
+		r.PushStep(step)
+		defer r.PopStep()
+	}
+	s.recChecker.Check(s.curPath)
+
+	// Cycle-detection for slice elements (see NOTE in compareSlice).
+	t := step.Type()
+	vx, vy := step.Values()
+	if si, ok := step.(SliceIndex); ok && si.isSlice && vx.IsValid() && vy.IsValid() {
+		px, py := vx.Addr(), vy.Addr()
+		if eq, visited := s.curPtrs.Push(px, py); visited {
+			s.report(eq, reportByCycle)
+			return
+		}
+		defer s.curPtrs.Pop(px, py)
+	}
+
+	// Rule 1: Check whether an option applies on this node in the value tree.
+	if s.tryOptions(t, vx, vy) {
+		return
+	}
+
+	// Rule 2: Check whether the type has a valid Equal method.
+	if s.tryMethod(t, vx, vy) {
+		return
+	}
+
+	// Rule 3: Compare based on the underlying kind.
+	switch t.Kind() {
+	case reflect.Bool:
+		s.report(vx.Bool() == vy.Bool(), 0)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		s.report(vx.Int() == vy.Int(), 0)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		s.report(vx.Uint() == vy.Uint(), 0)
+	case reflect.Float32, reflect.Float64:
+		s.report(vx.Float() == vy.Float(), 0)
+	case reflect.Complex64, reflect.Complex128:
+		s.report(vx.Complex() == vy.Complex(), 0)
+	case reflect.String:
+		s.report(vx.String() == vy.String(), 0)
+	case reflect.Chan, reflect.UnsafePointer:
+		s.report(vx.Pointer() == vy.Pointer(), 0)
+	case reflect.Func:
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+	case reflect.Struct:
+		s.compareStruct(t, vx, vy)
+	case reflect.Slice, reflect.Array:
+		s.compareSlice(t, vx, vy)
+	case reflect.Map:
+		s.compareMap(t, vx, vy)
+	case reflect.Ptr:
+		s.comparePtr(t, vx, vy)
+	case reflect.Interface:
+		s.compareInterface(t, vx, vy)
+	default:
+		panic(fmt.Sprintf("%v kind not handled", t.Kind()))
+	}
+}
+
+func (s *state) tryOptions(t reflect.Type, vx, vy reflect.Value) bool {
+	// Evaluate all filters and apply the remaining options.
+	if opt := s.opts.filter(s, t, vx, vy); opt != nil {
+		opt.apply(s, vx, vy)
+		return true
+	}
+	return false
+}
+
+func (s *state) tryMethod(t reflect.Type, vx, vy reflect.Value) bool {
+	// Check if this type even has an Equal method.
+	m, ok := t.MethodByName("Equal")
+	if !ok || !function.IsType(m.Type, function.EqualAssignable) {
+		return false
+	}
+
+	eq := s.callTTBFunc(m.Func, vx, vy)
+	s.report(eq, reportByMethod)
+	return true
+}
+
+func (s *state) callTRFunc(f, v reflect.Value, step Transform) reflect.Value {
+	v = sanitizeValue(v, f.Type().In(0))
+	if !s.dynChecker.Next() {
+		return f.Call([]reflect.Value{v})[0]
+	}
+
+	// Run the function twice and ensure that we get the same results back.
+	// We run in goroutines so that the race detector (if enabled) can detect
+	// unsafe mutations to the input.
+	c := make(chan reflect.Value)
+	go detectRaces(c, f, v)
+	got := <-c
+	want := f.Call([]reflect.Value{v})[0]
+	if step.vx, step.vy = got, want; !s.statelessCompare(step).Equal() {
+		// To avoid false-positives with non-reflexive equality operations,
+		// we sanity check whether a value is equal to itself.
+		if step.vx, step.vy = want, want; !s.statelessCompare(step).Equal() {
+			return want
+		}
+		panic(fmt.Sprintf("non-deterministic function detected: %s", function.NameOf(f)))
+	}
+	return want
+}
+
+func (s *state) callTTBFunc(f, x, y reflect.Value) bool {
+	x = sanitizeValue(x, f.Type().In(0))
+	y = sanitizeValue(y, f.Type().In(1))
+	if !s.dynChecker.Next() {
+		return f.Call([]reflect.Value{x, y})[0].Bool()
+	}
+
+	// Swapping the input arguments is sufficient to check that
+	// f is symmetric and deterministic.
+	// We run in goroutines so that the race detector (if enabled) can detect
+	// unsafe mutations to the input.
+	c := make(chan reflect.Value)
+	go detectRaces(c, f, y, x)
+	got := <-c
+	want := f.Call([]reflect.Value{x, y})[0].Bool()
+	if !got.IsValid() || got.Bool() != want {
+		panic(fmt.Sprintf("non-deterministic or non-symmetric function detected: %s", function.NameOf(f)))
+	}
+	return want
+}
+
+func detectRaces(c chan<- reflect.Value, f reflect.Value, vs ...reflect.Value) {
+	var ret reflect.Value
+	defer func() {
+		recover() // Ignore panics, let the other call to f panic instead
+		c <- ret
+	}()
+	ret = f.Call(vs)[0]
+}
+
+// sanitizeValue converts nil interfaces of type T to those of type R,
+// assuming that T is assignable to R.
+// Otherwise, it returns the input value as is.
+func sanitizeValue(v reflect.Value, t reflect.Type) reflect.Value {
+	// TODO(≥go1.10): Workaround for reflect bug (https://golang.org/issue/22143).
+	if !flags.AtLeastGo110 {
+		if v.Kind() == reflect.Interface && v.IsNil() && v.Type() != t {
+			return reflect.New(t).Elem()
+		}
+	}
+	return v
+}
+
+func (s *state) compareStruct(t reflect.Type, vx, vy reflect.Value) {
+	var addr bool
+	var vax, vay reflect.Value // Addressable versions of vx and vy
+
+	var mayForce, mayForceInit bool
+	step := StructField{&structField{}}
+	for i := 0; i < t.NumField(); i++ {
+		step.typ = t.Field(i).Type
+		step.vx = vx.Field(i)
+		step.vy = vy.Field(i)
+		step.name = t.Field(i).Name
+		step.idx = i
+		step.unexported = !isExported(step.name)
+		if step.unexported {
+			if step.name == "_" {
+				continue
+			}
+			// Defer checking of unexported fields until later to give an
+			// Ignore a chance to ignore the field.
+			if !vax.IsValid() || !vay.IsValid() {
+				// For retrieveUnexportedField to work, the parent struct must
+				// be addressable. Create a new copy of the values if
+				// necessary to make them addressable.
+				addr = vx.CanAddr() || vy.CanAddr()
+				vax = makeAddressable(vx)
+				vay = makeAddressable(vy)
+			}
+			if !mayForceInit {
+				for _, xf := range s.exporters {
+					mayForce = mayForce || xf(t)
+				}
+				mayForceInit = true
+			}
+			step.mayForce = mayForce
+			step.paddr = addr
+			step.pvx = vax
+			step.pvy = vay
+			step.field = t.Field(i)
+		}
+		s.compareAny(step)
+	}
+}
+
+func (s *state) compareSlice(t reflect.Type, vx, vy reflect.Value) {
+	isSlice := t.Kind() == reflect.Slice
+	if isSlice && (vx.IsNil() || vy.IsNil()) {
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+		return
+	}
+
+	// NOTE: It is incorrect to call curPtrs.Push on the slice header pointer
+	// since slices represents a list of pointers, rather than a single pointer.
+	// The pointer checking logic must be handled on a per-element basis
+	// in compareAny.
+	//
+	// A slice header (see reflect.SliceHeader) in Go is a tuple of a starting
+	// pointer P, a length N, and a capacity C. Supposing each slice element has
+	// a memory size of M, then the slice is equivalent to the list of pointers:
+	//	[P+i*M for i in range(N)]
+	//
+	// For example, v[:0] and v[:1] are slices with the same starting pointer,
+	// but they are clearly different values. Using the slice pointer alone
+	// violates the assumption that equal pointers implies equal values.
+
+	step := SliceIndex{&sliceIndex{pathStep: pathStep{typ: t.Elem()}, isSlice: isSlice}}
+	withIndexes := func(ix, iy int) SliceIndex {
+		if ix >= 0 {
+			step.vx, step.xkey = vx.Index(ix), ix
+		} else {
+			step.vx, step.xkey = reflect.Value{}, -1
+		}
+		if iy >= 0 {
+			step.vy, step.ykey = vy.Index(iy), iy
+		} else {
+			step.vy, step.ykey = reflect.Value{}, -1
+		}
+		return step
+	}
+
+	// Ignore options are able to ignore missing elements in a slice.
+	// However, detecting these reliably requires an optimal differencing
+	// algorithm, for which diff.Difference is not.
+	//
+	// Instead, we first iterate through both slices to detect which elements
+	// would be ignored if standing alone. The index of non-discarded elements
+	// are stored in a separate slice, which diffing is then performed on.
+	var indexesX, indexesY []int
+	var ignoredX, ignoredY []bool
+	for ix := 0; ix < vx.Len(); ix++ {
+		ignored := s.statelessCompare(withIndexes(ix, -1)).NumDiff == 0
+		if !ignored {
+			indexesX = append(indexesX, ix)
+		}
+		ignoredX = append(ignoredX, ignored)
+	}
+	for iy := 0; iy < vy.Len(); iy++ {
+		ignored := s.statelessCompare(withIndexes(-1, iy)).NumDiff == 0
+		if !ignored {
+			indexesY = append(indexesY, iy)
+		}
+		ignoredY = append(ignoredY, ignored)
+	}
+
+	// Compute an edit-script for slices vx and vy (excluding ignored elements).
+	edits := diff.Difference(len(indexesX), len(indexesY), func(ix, iy int) diff.Result {
+		return s.statelessCompare(withIndexes(indexesX[ix], indexesY[iy]))
+	})
+
+	// Replay the ignore-scripts and the edit-script.
+	var ix, iy int
+	for ix < vx.Len() || iy < vy.Len() {
+		var e diff.EditType
+		switch {
+		case ix < len(ignoredX) && ignoredX[ix]:
+			e = diff.UniqueX
+		case iy < len(ignoredY) && ignoredY[iy]:
+			e = diff.UniqueY
+		default:
+			e, edits = edits[0], edits[1:]
+		}
+		switch e {
+		case diff.UniqueX:
+			s.compareAny(withIndexes(ix, -1))
+			ix++
+		case diff.UniqueY:
+			s.compareAny(withIndexes(-1, iy))
+			iy++
+		default:
+			s.compareAny(withIndexes(ix, iy))
+			ix++
+			iy++
+		}
+	}
+}
+
+func (s *state) compareMap(t reflect.Type, vx, vy reflect.Value) {
+	if vx.IsNil() || vy.IsNil() {
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+		return
+	}
+
+	// Cycle-detection for maps.
+	if eq, visited := s.curPtrs.Push(vx, vy); visited {
+		s.report(eq, reportByCycle)
+		return
+	}
+	defer s.curPtrs.Pop(vx, vy)
+
+	// We combine and sort the two map keys so that we can perform the
+	// comparisons in a deterministic order.
+	step := MapIndex{&mapIndex{pathStep: pathStep{typ: t.Elem()}}}
+	for _, k := range value.SortKeys(append(vx.MapKeys(), vy.MapKeys()...)) {
+		step.vx = vx.MapIndex(k)
+		step.vy = vy.MapIndex(k)
+		step.key = k
+		if !step.vx.IsValid() && !step.vy.IsValid() {
+			// It is possible for both vx and vy to be invalid if the
+			// key contained a NaN value in it.
+			//
+			// Even with the ability to retrieve NaN keys in Go 1.12,
+			// there still isn't a sensible way to compare the values since
+			// a NaN key may map to multiple unordered values.
+			// The most reasonable way to compare NaNs would be to compare the
+			// set of values. However, this is impossible to do efficiently
+			// since set equality is provably an O(n^2) operation given only
+			// an Equal function. If we had a Less function or Hash function,
+			// this could be done in O(n*log(n)) or O(n), respectively.
+			//
+			// Rather than adding complex logic to deal with NaNs, make it
+			// the user's responsibility to compare such obscure maps.
+			const help = "consider providing a Comparer to compare the map"
+			panic(fmt.Sprintf("%#v has map key with NaNs\n%s", s.curPath, help))
+		}
+		s.compareAny(step)
+	}
+}
+
+func (s *state) comparePtr(t reflect.Type, vx, vy reflect.Value) {
+	if vx.IsNil() || vy.IsNil() {
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+		return
+	}
+
+	// Cycle-detection for pointers.
+	if eq, visited := s.curPtrs.Push(vx, vy); visited {
+		s.report(eq, reportByCycle)
+		return
+	}
+	defer s.curPtrs.Pop(vx, vy)
+
+	vx, vy = vx.Elem(), vy.Elem()
+	s.compareAny(Indirect{&indirect{pathStep{t.Elem(), vx, vy}}})
+}
+
+func (s *state) compareInterface(t reflect.Type, vx, vy reflect.Value) {
+	if vx.IsNil() || vy.IsNil() {
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+		return
+	}
+	vx, vy = vx.Elem(), vy.Elem()
+	if vx.Type() != vy.Type() {
+		s.report(false, 0)
+		return
+	}
+	s.compareAny(TypeAssertion{&typeAssertion{pathStep{vx.Type(), vx, vy}}})
+}
+
+func (s *state) report(eq bool, rf resultFlags) {
+	if rf&reportByIgnore == 0 {
+		if eq {
+			s.result.NumSame++
+			rf |= reportEqual
+		} else {
+			s.result.NumDiff++
+			rf |= reportUnequal
+		}
+	}
+	for _, r := range s.reporters {
+		r.Report(Result{flags: rf})
+	}
+}
+
+// recChecker tracks the state needed to periodically perform checks that
+// user provided transformers are not stuck in an infinitely recursive cycle.
+type recChecker struct{ next int }
+
+// Check scans the Path for any recursive transformers and panics when any
+// recursive transformers are detected. Note that the presence of a
+// recursive Transformer does not necessarily imply an infinite cycle.
+// As such, this check only activates after some minimal number of path steps.
+func (rc *recChecker) Check(p Path) {
+	const minLen = 1 << 16
+	if rc.next == 0 {
+		rc.next = minLen
+	}
+	if len(p) < rc.next {
+		return
+	}
+	rc.next <<= 1
+
+	// Check whether the same transformer has appeared at least twice.
+	var ss []string
+	m := map[Option]int{}
+	for _, ps := range p {
+		if t, ok := ps.(Transform); ok {
+			t := t.Option()
+			if m[t] == 1 { // Transformer was used exactly once before
+				tf := t.(*transformer).fnc.Type()
+				ss = append(ss, fmt.Sprintf("%v: %v => %v", t, tf.In(0), tf.Out(0)))
+			}
+			m[t]++
+		}
+	}
+	if len(ss) > 0 {
+		const warning = "recursive set of Transformers detected"
+		const help = "consider using cmpopts.AcyclicTransformer"
+		set := strings.Join(ss, "\n\t")
+		panic(fmt.Sprintf("%s:\n\t%s\n%s", warning, set, help))
+	}
+}
+
+// dynChecker tracks the state needed to periodically perform checks that
+// user provided functions are symmetric and deterministic.
+// The zero value is safe for immediate use.
+type dynChecker struct{ curr, next int }
+
+// Next increments the state and reports whether a check should be performed.
+//
+// Checks occur every Nth function call, where N is a triangular number:
+//	0 1 3 6 10 15 21 28 36 45 55 66 78 91 105 120 136 153 171 190 ...
+// See https://en.wikipedia.org/wiki/Triangular_number
+//
+// This sequence ensures that the cost of checks drops significantly as
+// the number of functions calls grows larger.
+func (dc *dynChecker) Next() bool {
+	ok := dc.curr == dc.next
+	if ok {
+		dc.curr = 0
+		dc.next++
+	}
+	dc.curr++
+	return ok
+}
+
+// makeAddressable returns a value that is always addressable.
+// It returns the input verbatim if it is already addressable,
+// otherwise it creates a new value and returns an addressable copy.
+func makeAddressable(v reflect.Value) reflect.Value {
+	if v.CanAddr() {
+		return v
+	}
+	vc := reflect.New(v.Type()).Elem()
+	vc.Set(v)
+	return vc
+}

vendor/github.com/google/go-cmp/cmp/export_panic.go

@@ -0,0 +1,15 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build purego
+
+package cmp
+
+import "reflect"
+
+const supportExporters = false
+
+func retrieveUnexportedField(reflect.Value, reflect.StructField, bool) reflect.Value {
+	panic("no support for forcibly accessing unexported fields")
+}

vendor/github.com/google/go-cmp/cmp/export_unsafe.go

@@ -0,0 +1,35 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !purego
+
+package cmp
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+const supportExporters = true
+
+// retrieveUnexportedField uses unsafe to forcibly retrieve any field from
+// a struct such that the value has read-write permissions.
+//
+// The parent struct, v, must be addressable, while f must be a StructField
+// describing the field to retrieve. If addr is false,
+// then the returned value will be shallowed copied to be non-addressable.
+func retrieveUnexportedField(v reflect.Value, f reflect.StructField, addr bool) reflect.Value {
+	ve := reflect.NewAt(f.Type, unsafe.Pointer(uintptr(unsafe.Pointer(v.UnsafeAddr()))+f.Offset)).Elem()
+	if !addr {
+		// A field is addressable if and only if the struct is addressable.
+		// If the original parent value was not addressable, shallow copy the
+		// value to make it non-addressable to avoid leaking an implementation
+		// detail of how forcibly exporting a field works.
+		if ve.Kind() == reflect.Interface && ve.IsNil() {
+			return reflect.Zero(f.Type)
+		}
+		return reflect.ValueOf(ve.Interface()).Convert(f.Type)
+	}
+	return ve
+}

vendor/github.com/google/go-cmp/cmp/internal/diff/debug_disable.go

@@ -0,0 +1,17 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !cmp_debug
+
+package diff
+
+var debug debugger
+
+type debugger struct{}
+
+func (debugger) Begin(_, _ int, f EqualFunc, _, _ *EditScript) EqualFunc {
+	return f
+}
+func (debugger) Update() {}
+func (debugger) Finish() {}

vendor/github.com/google/go-cmp/cmp/internal/diff/debug_enable.go

@@ -0,0 +1,122 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build cmp_debug
+
+package diff
+
+import (
+	"fmt"
+	"strings"
+	"sync"
+	"time"
+)
+
+// The algorithm can be seen running in real-time by enabling debugging:
+//	go test -tags=cmp_debug -v
+//
+// Example output:
+//	=== RUN   TestDifference/#34
+//	┌───────────────────────────────┐
+//	│ \ · · · · · · · · · · · · · · │
+//	│ · # · · · · · · · · · · · · · │
+//	│ · \ · · · · · · · · · · · · · │
+//	│ · · \ · · · · · · · · · · · · │
+//	│ · · · X # · · · · · · · · · · │
+//	│ · · · # \ · · · · · · · · · · │
+//	│ · · · · · # # · · · · · · · · │
+//	│ · · · · · # \ · · · · · · · · │
+//	│ · · · · · · · \ · · · · · · · │
+//	│ · · · · · · · · \ · · · · · · │
+//	│ · · · · · · · · · \ · · · · · │
+//	│ · · · · · · · · · · \ · · # · │
+//	│ · · · · · · · · · · · \ # # · │
+//	│ · · · · · · · · · · · # # # · │
+//	│ · · · · · · · · · · # # # # · │
+//	│ · · · · · · · · · # # # # # · │
+//	│ · · · · · · · · · · · · · · \ │
+//	└───────────────────────────────┘
+//	[.Y..M.XY......YXYXY.|]
+//
+// The grid represents the edit-graph where the horizontal axis represents
+// list X and the vertical axis represents list Y. The start of the two lists
+// is the top-left, while the ends are the bottom-right. The '·' represents
+// an unexplored node in the graph. The '\' indicates that the two symbols
+// from list X and Y are equal. The 'X' indicates that two symbols are similar
+// (but not exactly equal) to each other. The '#' indicates that the two symbols
+// are different (and not similar). The algorithm traverses this graph trying to
+// make the paths starting in the top-left and the bottom-right connect.
+//
+// The series of '.', 'X', 'Y', and 'M' characters at the bottom represents
+// the currently established path from the forward and reverse searches,
+// separated by a '|' character.
+
+const (
+	updateDelay  = 100 * time.Millisecond
+	finishDelay  = 500 * time.Millisecond
+	ansiTerminal = true // ANSI escape codes used to move terminal cursor
+)
+
+var debug debugger
+
+type debugger struct {
+	sync.Mutex
+	p1, p2           EditScript
+	fwdPath, revPath *EditScript
+	grid             []byte
+	lines            int
+}
+
+func (dbg *debugger) Begin(nx, ny int, f EqualFunc, p1, p2 *EditScript) EqualFunc {
+	dbg.Lock()
+	dbg.fwdPath, dbg.revPath = p1, p2
+	top := "┌─" + strings.Repeat("──", nx) + "┐\n"
+	row := "│ " + strings.Repeat("· ", nx) + "│\n"
+	btm := "└─" + strings.Repeat("──", nx) + "┘\n"
+	dbg.grid = []byte(top + strings.Repeat(row, ny) + btm)
+	dbg.lines = strings.Count(dbg.String(), "\n")
+	fmt.Print(dbg)
+
+	// Wrap the EqualFunc so that we can intercept each result.
+	return func(ix, iy int) (r Result) {
+		cell := dbg.grid[len(top)+iy*len(row):][len("│ ")+len("· ")*ix:][:len("·")]
+		for i := range cell {
+			cell[i] = 0 // Zero out the multiple bytes of UTF-8 middle-dot
+		}
+		switch r = f(ix, iy); {
+		case r.Equal():
+			cell[0] = '\\'
+		case r.Similar():
+			cell[0] = 'X'
+		default:
+			cell[0] = '#'
+		}
+		return
+	}
+}
+
+func (dbg *debugger) Update() {
+	dbg.print(updateDelay)
+}
+
+func (dbg *debugger) Finish() {
+	dbg.print(finishDelay)
+	dbg.Unlock()
+}
+
+func (dbg *debugger) String() string {
+	dbg.p1, dbg.p2 = *dbg.fwdPath, dbg.p2[:0]
+	for i := len(*dbg.revPath) - 1; i >= 0; i-- {
+		dbg.p2 = append(dbg.p2, (*dbg.revPath)[i])
+	}
+	return fmt.Sprintf("%s[%v|%v]\n\n", dbg.grid, dbg.p1, dbg.p2)
+}
+
+func (dbg *debugger) print(d time.Duration) {
+	if ansiTerminal {
+		fmt.Printf("\x1b[%dA", dbg.lines) // Reset terminal cursor
+	}
+	fmt.Print(dbg)
+	time.Sleep(d)
+}

vendor/github.com/google/go-cmp/cmp/internal/diff/diff.go

@@ -0,0 +1,398 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package diff implements an algorithm for producing edit-scripts.
+// The edit-script is a sequence of operations needed to transform one list
+// of symbols into another (or vice-versa). The edits allowed are insertions,
+// deletions, and modifications. The summation of all edits is called the
+// Levenshtein distance as this problem is well-known in computer science.
+//
+// This package prioritizes performance over accuracy. That is, the run time
+// is more important than obtaining a minimal Levenshtein distance.
+package diff
+
+import (
+	"math/rand"
+	"time"
+
+	"github.com/google/go-cmp/cmp/internal/flags"
+)
+
+// EditType represents a single operation within an edit-script.
+type EditType uint8
+
+const (
+	// Identity indicates that a symbol pair is identical in both list X and Y.
+	Identity EditType = iota
+	// UniqueX indicates that a symbol only exists in X and not Y.
+	UniqueX
+	// UniqueY indicates that a symbol only exists in Y and not X.
+	UniqueY
+	// Modified indicates that a symbol pair is a modification of each other.
+	Modified
+)
+
+// EditScript represents the series of differences between two lists.
+type EditScript []EditType
+
+// String returns a human-readable string representing the edit-script where
+// Identity, UniqueX, UniqueY, and Modified are represented by the
+// '.', 'X', 'Y', and 'M' characters, respectively.
+func (es EditScript) String() string {
+	b := make([]byte, len(es))
+	for i, e := range es {
+		switch e {
+		case Identity:
+			b[i] = '.'
+		case UniqueX:
+			b[i] = 'X'
+		case UniqueY:
+			b[i] = 'Y'
+		case Modified:
+			b[i] = 'M'
+		default:
+			panic("invalid edit-type")
+		}
+	}
+	return string(b)
+}
+
+// stats returns a histogram of the number of each type of edit operation.
+func (es EditScript) stats() (s struct{ NI, NX, NY, NM int }) {
+	for _, e := range es {
+		switch e {
+		case Identity:
+			s.NI++
+		case UniqueX:
+			s.NX++
+		case UniqueY:
+			s.NY++
+		case Modified:
+			s.NM++
+		default:
+			panic("invalid edit-type")
+		}
+	}
+	return
+}
+
+// Dist is the Levenshtein distance and is guaranteed to be 0 if and only if
+// lists X and Y are equal.
+func (es EditScript) Dist() int { return len(es) - es.stats().NI }
+
+// LenX is the length of the X list.
+func (es EditScript) LenX() int { return len(es) - es.stats().NY }
+
+// LenY is the length of the Y list.
+func (es EditScript) LenY() int { return len(es) - es.stats().NX }
+
+// EqualFunc reports whether the symbols at indexes ix and iy are equal.
+// When called by Difference, the index is guaranteed to be within nx and ny.
+type EqualFunc func(ix int, iy int) Result
+
+// Result is the result of comparison.
+// NumSame is the number of sub-elements that are equal.
+// NumDiff is the number of sub-elements that are not equal.
+type Result struct{ NumSame, NumDiff int }
+
+// BoolResult returns a Result that is either Equal or not Equal.
+func BoolResult(b bool) Result {
+	if b {
+		return Result{NumSame: 1} // Equal, Similar
+	} else {
+		return Result{NumDiff: 2} // Not Equal, not Similar
+	}
+}
+
+// Equal indicates whether the symbols are equal. Two symbols are equal
+// if and only if NumDiff == 0. If Equal, then they are also Similar.
+func (r Result) Equal() bool { return r.NumDiff == 0 }
+
+// Similar indicates whether two symbols are similar and may be represented
+// by using the Modified type. As a special case, we consider binary comparisons
+// (i.e., those that return Result{1, 0} or Result{0, 1}) to be similar.
+//
+// The exact ratio of NumSame to NumDiff to determine similarity may change.
+func (r Result) Similar() bool {
+	// Use NumSame+1 to offset NumSame so that binary comparisons are similar.
+	return r.NumSame+1 >= r.NumDiff
+}
+
+var randBool = rand.New(rand.NewSource(time.Now().Unix())).Intn(2) == 0
+
+// Difference reports whether two lists of lengths nx and ny are equal
+// given the definition of equality provided as f.
+//
+// This function returns an edit-script, which is a sequence of operations
+// needed to convert one list into the other. The following invariants for
+// the edit-script are maintained:
+//	• eq == (es.Dist()==0)
+//	• nx == es.LenX()
+//	• ny == es.LenY()
+//
+// This algorithm is not guaranteed to be an optimal solution (i.e., one that
+// produces an edit-script with a minimal Levenshtein distance). This algorithm
+// favors performance over optimality. The exact output is not guaranteed to
+// be stable and may change over time.
+func Difference(nx, ny int, f EqualFunc) (es EditScript) {
+	// This algorithm is based on traversing what is known as an "edit-graph".
+	// See Figure 1 from "An O(ND) Difference Algorithm and Its Variations"
+	// by Eugene W. Myers. Since D can be as large as N itself, this is
+	// effectively O(N^2). Unlike the algorithm from that paper, we are not
+	// interested in the optimal path, but at least some "decent" path.
+	//
+	// For example, let X and Y be lists of symbols:
+	//	X = [A B C A B B A]
+	//	Y = [C B A B A C]
+	//
+	// The edit-graph can be drawn as the following:
+	//	   A B C A B B A
+	//	  ┌─────────────┐
+	//	C │_|_|\|_|_|_|_│ 0
+	//	B │_|\|_|_|\|\|_│ 1
+	//	A │\|_|_|\|_|_|\│ 2
+	//	B │_|\|_|_|\|\|_│ 3
+	//	A │\|_|_|\|_|_|\│ 4
+	//	C │ | |\| | | | │ 5
+	//	  └─────────────┘ 6
+	//	   0 1 2 3 4 5 6 7
+	//
+	// List X is written along the horizontal axis, while list Y is written
+	// along the vertical axis. At any point on this grid, if the symbol in
+	// list X matches the corresponding symbol in list Y, then a '\' is drawn.
+	// The goal of any minimal edit-script algorithm is to find a path from the
+	// top-left corner to the bottom-right corner, while traveling through the
+	// fewest horizontal or vertical edges.
+	// A horizontal edge is equivalent to inserting a symbol from list X.
+	// A vertical edge is equivalent to inserting a symbol from list Y.
+	// A diagonal edge is equivalent to a matching symbol between both X and Y.
+
+	// Invariants:
+	//	• 0 ≤ fwdPath.X ≤ (fwdFrontier.X, revFrontier.X) ≤ revPath.X ≤ nx
+	//	• 0 ≤ fwdPath.Y ≤ (fwdFrontier.Y, revFrontier.Y) ≤ revPath.Y ≤ ny
+	//
+	// In general:
+	//	• fwdFrontier.X < revFrontier.X
+	//	• fwdFrontier.Y < revFrontier.Y
+	// Unless, it is time for the algorithm to terminate.
+	fwdPath := path{+1, point{0, 0}, make(EditScript, 0, (nx+ny)/2)}
+	revPath := path{-1, point{nx, ny}, make(EditScript, 0)}
+	fwdFrontier := fwdPath.point // Forward search frontier
+	revFrontier := revPath.point // Reverse search frontier
+
+	// Search budget bounds the cost of searching for better paths.
+	// The longest sequence of non-matching symbols that can be tolerated is
+	// approximately the square-root of the search budget.
+	searchBudget := 4 * (nx + ny) // O(n)
+
+	// Running the tests with the "cmp_debug" build tag prints a visualization
+	// of the algorithm running in real-time. This is educational for
+	// understanding how the algorithm works. See debug_enable.go.
+	f = debug.Begin(nx, ny, f, &fwdPath.es, &revPath.es)
+
+	// The algorithm below is a greedy, meet-in-the-middle algorithm for
+	// computing sub-optimal edit-scripts between two lists.
+	//
+	// The algorithm is approximately as follows:
+	//	• Searching for differences switches back-and-forth between
+	//	a search that starts at the beginning (the top-left corner), and
+	//	a search that starts at the end (the bottom-right corner). The goal of
+	//	the search is connect with the search from the opposite corner.
+	//	• As we search, we build a path in a greedy manner, where the first
+	//	match seen is added to the path (this is sub-optimal, but provides a
+	//	decent result in practice). When matches are found, we try the next pair
+	//	of symbols in the lists and follow all matches as far as possible.
+	//	• When searching for matches, we search along a diagonal going through
+	//	through the "frontier" point. If no matches are found, we advance the
+	//	frontier towards the opposite corner.
+	//	• This algorithm terminates when either the X coordinates or the
+	//	Y coordinates of the forward and reverse frontier points ever intersect.
+
+	// This algorithm is correct even if searching only in the forward direction
+	// or in the reverse direction. We do both because it is commonly observed
+	// that two lists commonly differ because elements were added to the front
+	// or end of the other list.
+	//
+	// Non-deterministically start with either the forward or reverse direction
+	// to introduce some deliberate instability so that we have the flexibility
+	// to change this algorithm in the future.
+	if flags.Deterministic || randBool {
+		goto forwardSearch
+	} else {
+		goto reverseSearch
+	}
+
+forwardSearch:
+	{
+		// Forward search from the beginning.
+		if fwdFrontier.X >= revFrontier.X || fwdFrontier.Y >= revFrontier.Y || searchBudget == 0 {
+			goto finishSearch
+		}
+		for stop1, stop2, i := false, false, 0; !(stop1 && stop2) && searchBudget > 0; i++ {
+			// Search in a diagonal pattern for a match.
+			z := zigzag(i)
+			p := point{fwdFrontier.X + z, fwdFrontier.Y - z}
+			switch {
+			case p.X >= revPath.X || p.Y < fwdPath.Y:
+				stop1 = true // Hit top-right corner
+			case p.Y >= revPath.Y || p.X < fwdPath.X:
+				stop2 = true // Hit bottom-left corner
+			case f(p.X, p.Y).Equal():
+				// Match found, so connect the path to this point.
+				fwdPath.connect(p, f)
+				fwdPath.append(Identity)
+				// Follow sequence of matches as far as possible.
+				for fwdPath.X < revPath.X && fwdPath.Y < revPath.Y {
+					if !f(fwdPath.X, fwdPath.Y).Equal() {
+						break
+					}
+					fwdPath.append(Identity)
+				}
+				fwdFrontier = fwdPath.point
+				stop1, stop2 = true, true
+			default:
+				searchBudget-- // Match not found
+			}
+			debug.Update()
+		}
+		// Advance the frontier towards reverse point.
+		if revPath.X-fwdFrontier.X >= revPath.Y-fwdFrontier.Y {
+			fwdFrontier.X++
+		} else {
+			fwdFrontier.Y++
+		}
+		goto reverseSearch
+	}
+
+reverseSearch:
+	{
+		// Reverse search from the end.
+		if fwdFrontier.X >= revFrontier.X || fwdFrontier.Y >= revFrontier.Y || searchBudget == 0 {
+			goto finishSearch
+		}
+		for stop1, stop2, i := false, false, 0; !(stop1 && stop2) && searchBudget > 0; i++ {
+			// Search in a diagonal pattern for a match.
+			z := zigzag(i)
+			p := point{revFrontier.X - z, revFrontier.Y + z}
+			switch {
+			case fwdPath.X >= p.X || revPath.Y < p.Y:
+				stop1 = true // Hit bottom-left corner
+			case fwdPath.Y >= p.Y || revPath.X < p.X:
+				stop2 = true // Hit top-right corner
+			case f(p.X-1, p.Y-1).Equal():
+				// Match found, so connect the path to this point.
+				revPath.connect(p, f)
+				revPath.append(Identity)
+				// Follow sequence of matches as far as possible.
+				for fwdPath.X < revPath.X && fwdPath.Y < revPath.Y {
+					if !f(revPath.X-1, revPath.Y-1).Equal() {
+						break
+					}
+					revPath.append(Identity)
+				}
+				revFrontier = revPath.point
+				stop1, stop2 = true, true
+			default:
+				searchBudget-- // Match not found
+			}
+			debug.Update()
+		}
+		// Advance the frontier towards forward point.
+		if revFrontier.X-fwdPath.X >= revFrontier.Y-fwdPath.Y {
+			revFrontier.X--
+		} else {
+			revFrontier.Y--
+		}
+		goto forwardSearch
+	}
+
+finishSearch:
+	// Join the forward and reverse paths and then append the reverse path.
+	fwdPath.connect(revPath.point, f)
+	for i := len(revPath.es) - 1; i >= 0; i-- {
+		t := revPath.es[i]
+		revPath.es = revPath.es[:i]
+		fwdPath.append(t)
+	}
+	debug.Finish()
+	return fwdPath.es
+}
+
+type path struct {
+	dir   int // +1 if forward, -1 if reverse
+	point     // Leading point of the EditScript path
+	es    EditScript
+}
+
+// connect appends any necessary Identity, Modified, UniqueX, or UniqueY types
+// to the edit-script to connect p.point to dst.
+func (p *path) connect(dst point, f EqualFunc) {
+	if p.dir > 0 {
+		// Connect in forward direction.
+		for dst.X > p.X && dst.Y > p.Y {
+			switch r := f(p.X, p.Y); {
+			case r.Equal():
+				p.append(Identity)
+			case r.Similar():
+				p.append(Modified)
+			case dst.X-p.X >= dst.Y-p.Y:
+				p.append(UniqueX)
+			default:
+				p.append(UniqueY)
+			}
+		}
+		for dst.X > p.X {
+			p.append(UniqueX)
+		}
+		for dst.Y > p.Y {
+			p.append(UniqueY)
+		}
+	} else {
+		// Connect in reverse direction.
+		for p.X > dst.X && p.Y > dst.Y {
+			switch r := f(p.X-1, p.Y-1); {
+			case r.Equal():
+				p.append(Identity)
+			case r.Similar():
+				p.append(Modified)
+			case p.Y-dst.Y >= p.X-dst.X:
+				p.append(UniqueY)
+			default:
+				p.append(UniqueX)
+			}
+		}
+		for p.X > dst.X {
+			p.append(UniqueX)
+		}
+		for p.Y > dst.Y {
+			p.append(UniqueY)
+		}
+	}
+}
+
+func (p *path) append(t EditType) {
+	p.es = append(p.es, t)
+	switch t {
+	case Identity, Modified:
+		p.add(p.dir, p.dir)
+	case UniqueX:
+		p.add(p.dir, 0)
+	case UniqueY:
+		p.add(0, p.dir)
+	}
+	debug.Update()
+}
+
+type point struct{ X, Y int }
+
+func (p *point) add(dx, dy int) { p.X += dx; p.Y += dy }
+
+// zigzag maps a consecutive sequence of integers to a zig-zag sequence.
+//	[0 1 2 3 4 5 ...] => [0 -1 +1 -2 +2 ...]
+func zigzag(x int) int {
+	if x&1 != 0 {
+		x = ^x
+	}
+	return x >> 1
+}

vendor/github.com/google/go-cmp/cmp/internal/flags/flags.go

@@ -0,0 +1,9 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flags
+
+// Deterministic controls whether the output of Diff should be deterministic.
+// This is only used for testing.
+var Deterministic bool

vendor/github.com/google/go-cmp/cmp/internal/flags/toolchain_legacy.go

@@ -0,0 +1,10 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.10
+
+package flags
+
+// AtLeastGo110 reports whether the Go toolchain is at least Go 1.10.
+const AtLeastGo110 = false

vendor/github.com/google/go-cmp/cmp/internal/flags/toolchain_recent.go

@@ -0,0 +1,10 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.10
+
+package flags
+
+// AtLeastGo110 reports whether the Go toolchain is at least Go 1.10.
+const AtLeastGo110 = true

vendor/github.com/google/go-cmp/cmp/internal/function/func.go

@@ -0,0 +1,99 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package function provides functionality for identifying function types.
+package function
+
+import (
+	"reflect"
+	"regexp"
+	"runtime"
+	"strings"
+)
+
+type funcType int
+
+const (
+	_ funcType = iota
+
+	tbFunc  // func(T) bool
+	ttbFunc // func(T, T) bool
+	trbFunc // func(T, R) bool
+	tibFunc // func(T, I) bool
+	trFunc  // func(T) R
+
+	Equal             = ttbFunc // func(T, T) bool
+	EqualAssignable   = tibFunc // func(T, I) bool; encapsulates func(T, T) bool
+	Transformer       = trFunc  // func(T) R
+	ValueFilter       = ttbFunc // func(T, T) bool
+	Less              = ttbFunc // func(T, T) bool
+	ValuePredicate    = tbFunc  // func(T) bool
+	KeyValuePredicate = trbFunc // func(T, R) bool
+)
+
+var boolType = reflect.TypeOf(true)
+
+// IsType reports whether the reflect.Type is of the specified function type.
+func IsType(t reflect.Type, ft funcType) bool {
+	if t == nil || t.Kind() != reflect.Func || t.IsVariadic() {
+		return false
+	}
+	ni, no := t.NumIn(), t.NumOut()
+	switch ft {
+	case tbFunc: // func(T) bool
+		if ni == 1 && no == 1 && t.Out(0) == boolType {
+			return true
+		}
+	case ttbFunc: // func(T, T) bool
+		if ni == 2 && no == 1 && t.In(0) == t.In(1) && t.Out(0) == boolType {
+			return true
+		}
+	case trbFunc: // func(T, R) bool
+		if ni == 2 && no == 1 && t.Out(0) == boolType {
+			return true
+		}
+	case tibFunc: // func(T, I) bool
+		if ni == 2 && no == 1 && t.In(0).AssignableTo(t.In(1)) && t.Out(0) == boolType {
+			return true
+		}
+	case trFunc: // func(T) R
+		if ni == 1 && no == 1 {
+			return true
+		}
+	}
+	return false
+}
+
+var lastIdentRx = regexp.MustCompile(`[_\p{L}][_\p{L}\p{N}]*$`)
+
+// NameOf returns the name of the function value.
+func NameOf(v reflect.Value) string {
+	fnc := runtime.FuncForPC(v.Pointer())
+	if fnc == nil {
+		return "<unknown>"
+	}
+	fullName := fnc.Name() // e.g., "long/path/name/mypkg.(*MyType).(long/path/name/mypkg.myMethod)-fm"
+
+	// Method closures have a "-fm" suffix.
+	fullName = strings.TrimSuffix(fullName, "-fm")
+
+	var name string
+	for len(fullName) > 0 {
+		inParen := strings.HasSuffix(fullName, ")")
+		fullName = strings.TrimSuffix(fullName, ")")
+
+		s := lastIdentRx.FindString(fullName)
+		if s == "" {
+			break
+		}
+		name = s + "." + name
+		fullName = strings.TrimSuffix(fullName, s)
+
+		if i := strings.LastIndexByte(fullName, '('); inParen && i >= 0 {
+			fullName = fullName[:i]
+		}
+		fullName = strings.TrimSuffix(fullName, ".")
+	}
+	return strings.TrimSuffix(name, ".")
+}

vendor/github.com/google/go-cmp/cmp/internal/value/name.go

@@ -0,0 +1,157 @@
+// Copyright 2020, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package value
+
+import (
+	"reflect"
+	"strconv"
+)
+
+// TypeString is nearly identical to reflect.Type.String,
+// but has an additional option to specify that full type names be used.
+func TypeString(t reflect.Type, qualified bool) string {
+	return string(appendTypeName(nil, t, qualified, false))
+}
+
+func appendTypeName(b []byte, t reflect.Type, qualified, elideFunc bool) []byte {
+	// BUG: Go reflection provides no way to disambiguate two named types
+	// of the same name and within the same package,
+	// but declared within the namespace of different functions.
+
+	// Named type.
+	if t.Name() != "" {
+		if qualified && t.PkgPath() != "" {
+			b = append(b, '"')
+			b = append(b, t.PkgPath()...)
+			b = append(b, '"')
+			b = append(b, '.')
+			b = append(b, t.Name()...)
+		} else {
+			b = append(b, t.String()...)
+		}
+		return b
+	}
+
+	// Unnamed type.
+	switch k := t.Kind(); k {
+	case reflect.Bool, reflect.String, reflect.UnsafePointer,
+		reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr,
+		reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
+		b = append(b, k.String()...)
+	case reflect.Chan:
+		if t.ChanDir() == reflect.RecvDir {
+			b = append(b, "<-"...)
+		}
+		b = append(b, "chan"...)
+		if t.ChanDir() == reflect.SendDir {
+			b = append(b, "<-"...)
+		}
+		b = append(b, ' ')
+		b = appendTypeName(b, t.Elem(), qualified, false)
+	case reflect.Func:
+		if !elideFunc {
+			b = append(b, "func"...)
+		}
+		b = append(b, '(')
+		for i := 0; i < t.NumIn(); i++ {
+			if i > 0 {
+				b = append(b, ", "...)
+			}
+			if i == t.NumIn()-1 && t.IsVariadic() {
+				b = append(b, "..."...)
+				b = appendTypeName(b, t.In(i).Elem(), qualified, false)
+			} else {
+				b = appendTypeName(b, t.In(i), qualified, false)
+			}
+		}
+		b = append(b, ')')
+		switch t.NumOut() {
+		case 0:
+			// Do nothing
+		case 1:
+			b = append(b, ' ')
+			b = appendTypeName(b, t.Out(0), qualified, false)
+		default:
+			b = append(b, " ("...)
+			for i := 0; i < t.NumOut(); i++ {
+				if i > 0 {
+					b = append(b, ", "...)
+				}
+				b = appendTypeName(b, t.Out(i), qualified, false)
+			}
+			b = append(b, ')')
+		}
+	case reflect.Struct:
+		b = append(b, "struct{ "...)
+		for i := 0; i < t.NumField(); i++ {
+			if i > 0 {
+				b = append(b, "; "...)
+			}
+			sf := t.Field(i)
+			if !sf.Anonymous {
+				if qualified && sf.PkgPath != "" {
+					b = append(b, '"')
+					b = append(b, sf.PkgPath...)
+					b = append(b, '"')
+					b = append(b, '.')
+				}
+				b = append(b, sf.Name...)
+				b = append(b, ' ')
+			}
+			b = appendTypeName(b, sf.Type, qualified, false)
+			if sf.Tag != "" {
+				b = append(b, ' ')
+				b = strconv.AppendQuote(b, string(sf.Tag))
+			}
+		}
+		if b[len(b)-1] == ' ' {
+			b = b[:len(b)-1]
+		} else {
+			b = append(b, ' ')
+		}
+		b = append(b, '}')
+	case reflect.Slice, reflect.Array:
+		b = append(b, '[')
+		if k == reflect.Array {
+			b = strconv.AppendUint(b, uint64(t.Len()), 10)
+		}
+		b = append(b, ']')
+		b = appendTypeName(b, t.Elem(), qualified, false)
+	case reflect.Map:
+		b = append(b, "map["...)
+		b = appendTypeName(b, t.Key(), qualified, false)
+		b = append(b, ']')
+		b = appendTypeName(b, t.Elem(), qualified, false)
+	case reflect.Ptr:
+		b = append(b, '*')
+		b = appendTypeName(b, t.Elem(), qualified, false)
+	case reflect.Interface:
+		b = append(b, "interface{ "...)
+		for i := 0; i < t.NumMethod(); i++ {
+			if i > 0 {
+				b = append(b, "; "...)
+			}
+			m := t.Method(i)
+			if qualified && m.PkgPath != "" {
+				b = append(b, '"')
+				b = append(b, m.PkgPath...)
+				b = append(b, '"')
+				b = append(b, '.')
+			}
+			b = append(b, m.Name...)
+			b = appendTypeName(b, m.Type, qualified, true)
+		}
+		if b[len(b)-1] == ' ' {
+			b = b[:len(b)-1]
+		} else {
+			b = append(b, ' ')
+		}
+		b = append(b, '}')
+	default:
+		panic("invalid kind: " + k.String())
+	}
+	return b
+}

vendor/github.com/google/go-cmp/cmp/internal/value/pointer_purego.go

@@ -0,0 +1,33 @@
+// Copyright 2018, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build purego
+
+package value
+
+import "reflect"
+
+// Pointer is an opaque typed pointer and is guaranteed to be comparable.
+type Pointer struct {
+	p uintptr
+	t reflect.Type
+}
+
+// PointerOf returns a Pointer from v, which must be a
+// reflect.Ptr, reflect.Slice, or reflect.Map.
+func PointerOf(v reflect.Value) Pointer {
+	// NOTE: Storing a pointer as an uintptr is technically incorrect as it
+	// assumes that the GC implementation does not use a moving collector.
+	return Pointer{v.Pointer(), v.Type()}
+}
+
+// IsNil reports whether the pointer is nil.
+func (p Pointer) IsNil() bool {
+	return p.p == 0
+}
+
+// Uintptr returns the pointer as a uintptr.
+func (p Pointer) Uintptr() uintptr {
+	return p.p
+}

vendor/github.com/google/go-cmp/cmp/internal/value/pointer_unsafe.go

@@ -0,0 +1,36 @@
+// Copyright 2018, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !purego
+
+package value
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+// Pointer is an opaque typed pointer and is guaranteed to be comparable.
+type Pointer struct {
+	p unsafe.Pointer
+	t reflect.Type
+}
+
+// PointerOf returns a Pointer from v, which must be a
+// reflect.Ptr, reflect.Slice, or reflect.Map.
+func PointerOf(v reflect.Value) Pointer {
+	// The proper representation of a pointer is unsafe.Pointer,
+	// which is necessary if the GC ever uses a moving collector.
+	return Pointer{unsafe.Pointer(v.Pointer()), v.Type()}
+}
+
+// IsNil reports whether the pointer is nil.
+func (p Pointer) IsNil() bool {
+	return p.p == nil
+}
+
+// Uintptr returns the pointer as a uintptr.
+func (p Pointer) Uintptr() uintptr {
+	return uintptr(p.p)
+}

vendor/github.com/google/go-cmp/cmp/internal/value/sort.go

@@ -0,0 +1,106 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package value
+
+import (
+	"fmt"
+	"math"
+	"reflect"
+	"sort"
+)
+
+// SortKeys sorts a list of map keys, deduplicating keys if necessary.
+// The type of each value must be comparable.
+func SortKeys(vs []reflect.Value) []reflect.Value {
+	if len(vs) == 0 {
+		return vs
+	}
+
+	// Sort the map keys.
+	sort.SliceStable(vs, func(i, j int) bool { return isLess(vs[i], vs[j]) })
+
+	// Deduplicate keys (fails for NaNs).
+	vs2 := vs[:1]
+	for _, v := range vs[1:] {
+		if isLess(vs2[len(vs2)-1], v) {
+			vs2 = append(vs2, v)
+		}
+	}
+	return vs2
+}
+
+// isLess is a generic function for sorting arbitrary map keys.
+// The inputs must be of the same type and must be comparable.
+func isLess(x, y reflect.Value) bool {
+	switch x.Type().Kind() {
+	case reflect.Bool:
+		return !x.Bool() && y.Bool()
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return x.Int() < y.Int()
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return x.Uint() < y.Uint()
+	case reflect.Float32, reflect.Float64:
+		// NOTE: This does not sort -0 as less than +0
+		// since Go maps treat -0 and +0 as equal keys.
+		fx, fy := x.Float(), y.Float()
+		return fx < fy || math.IsNaN(fx) && !math.IsNaN(fy)
+	case reflect.Complex64, reflect.Complex128:
+		cx, cy := x.Complex(), y.Complex()
+		rx, ix, ry, iy := real(cx), imag(cx), real(cy), imag(cy)
+		if rx == ry || (math.IsNaN(rx) && math.IsNaN(ry)) {
+			return ix < iy || math.IsNaN(ix) && !math.IsNaN(iy)
+		}
+		return rx < ry || math.IsNaN(rx) && !math.IsNaN(ry)
+	case reflect.Ptr, reflect.UnsafePointer, reflect.Chan:
+		return x.Pointer() < y.Pointer()
+	case reflect.String:
+		return x.String() < y.String()
+	case reflect.Array:
+		for i := 0; i < x.Len(); i++ {
+			if isLess(x.Index(i), y.Index(i)) {
+				return true
+			}
+			if isLess(y.Index(i), x.Index(i)) {
+				return false
+			}
+		}
+		return false
+	case reflect.Struct:
+		for i := 0; i < x.NumField(); i++ {
+			if isLess(x.Field(i), y.Field(i)) {
+				return true
+			}
+			if isLess(y.Field(i), x.Field(i)) {
+				return false
+			}
+		}
+		return false
+	case reflect.Interface:
+		vx, vy := x.Elem(), y.Elem()
+		if !vx.IsValid() || !vy.IsValid() {
+			return !vx.IsValid() && vy.IsValid()
+		}
+		tx, ty := vx.Type(), vy.Type()
+		if tx == ty {
+			return isLess(x.Elem(), y.Elem())
+		}
+		if tx.Kind() != ty.Kind() {
+			return vx.Kind() < vy.Kind()
+		}
+		if tx.String() != ty.String() {
+			return tx.String() < ty.String()
+		}
+		if tx.PkgPath() != ty.PkgPath() {
+			return tx.PkgPath() < ty.PkgPath()
+		}
+		// This can happen in rare situations, so we fallback to just comparing
+		// the unique pointer for a reflect.Type. This guarantees deterministic
+		// ordering within a program, but it is obviously not stable.
+		return reflect.ValueOf(vx.Type()).Pointer() < reflect.ValueOf(vy.Type()).Pointer()
+	default:
+		// Must be Func, Map, or Slice; which are not comparable.
+		panic(fmt.Sprintf("%T is not comparable", x.Type()))
+	}
+}

vendor/github.com/google/go-cmp/cmp/internal/value/zero.go

@@ -0,0 +1,48 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package value
+
+import (
+	"math"
+	"reflect"
+)
+
+// IsZero reports whether v is the zero value.
+// This does not rely on Interface and so can be used on unexported fields.
+func IsZero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Bool:
+		return v.Bool() == false
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return v.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return math.Float64bits(v.Float()) == 0
+	case reflect.Complex64, reflect.Complex128:
+		return math.Float64bits(real(v.Complex())) == 0 && math.Float64bits(imag(v.Complex())) == 0
+	case reflect.String:
+		return v.String() == ""
+	case reflect.UnsafePointer:
+		return v.Pointer() == 0
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Ptr, reflect.Map, reflect.Slice:
+		return v.IsNil()
+	case reflect.Array:
+		for i := 0; i < v.Len(); i++ {
+			if !IsZero(v.Index(i)) {
+				return false
+			}
+		}
+		return true
+	case reflect.Struct:
+		for i := 0; i < v.NumField(); i++ {
+			if !IsZero(v.Field(i)) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}

vendor/github.com/google/go-cmp/cmp/options.go

@@ -0,0 +1,552 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+	"regexp"
+	"strings"
+
+	"github.com/google/go-cmp/cmp/internal/function"
+)
+
+// Option configures for specific behavior of Equal and Diff. In particular,
+// the fundamental Option functions (Ignore, Transformer, and Comparer),
+// configure how equality is determined.
+//
+// The fundamental options may be composed with filters (FilterPath and
+// FilterValues) to control the scope over which they are applied.
+//
+// The cmp/cmpopts package provides helper functions for creating options that
+// may be used with Equal and Diff.
+type Option interface {
+	// filter applies all filters and returns the option that remains.
+	// Each option may only read s.curPath and call s.callTTBFunc.
+	//
+	// An Options is returned only if multiple comparers or transformers
+	// can apply simultaneously and will only contain values of those types
+	// or sub-Options containing values of those types.
+	filter(s *state, t reflect.Type, vx, vy reflect.Value) applicableOption
+}
+
+// applicableOption represents the following types:
+//	Fundamental: ignore | validator | *comparer | *transformer
+//	Grouping:    Options
+type applicableOption interface {
+	Option
+
+	// apply executes the option, which may mutate s or panic.
+	apply(s *state, vx, vy reflect.Value)
+}
+
+// coreOption represents the following types:
+//	Fundamental: ignore | validator | *comparer | *transformer
+//	Filters:     *pathFilter | *valuesFilter
+type coreOption interface {
+	Option
+	isCore()
+}
+
+type core struct{}
+
+func (core) isCore() {}
+
+// Options is a list of Option values that also satisfies the Option interface.
+// Helper comparison packages may return an Options value when packing multiple
+// Option values into a single Option. When this package processes an Options,
+// it will be implicitly expanded into a flat list.
+//
+// Applying a filter on an Options is equivalent to applying that same filter
+// on all individual options held within.
+type Options []Option
+
+func (opts Options) filter(s *state, t reflect.Type, vx, vy reflect.Value) (out applicableOption) {
+	for _, opt := range opts {
+		switch opt := opt.filter(s, t, vx, vy); opt.(type) {
+		case ignore:
+			return ignore{} // Only ignore can short-circuit evaluation
+		case validator:
+			out = validator{} // Takes precedence over comparer or transformer
+		case *comparer, *transformer, Options:
+			switch out.(type) {
+			case nil:
+				out = opt
+			case validator:
+				// Keep validator
+			case *comparer, *transformer, Options:
+				out = Options{out, opt} // Conflicting comparers or transformers
+			}
+		}
+	}
+	return out
+}
+
+func (opts Options) apply(s *state, _, _ reflect.Value) {
+	const warning = "ambiguous set of applicable options"
+	const help = "consider using filters to ensure at most one Comparer or Transformer may apply"
+	var ss []string
+	for _, opt := range flattenOptions(nil, opts) {
+		ss = append(ss, fmt.Sprint(opt))
+	}
+	set := strings.Join(ss, "\n\t")
+	panic(fmt.Sprintf("%s at %#v:\n\t%s\n%s", warning, s.curPath, set, help))
+}
+
+func (opts Options) String() string {
+	var ss []string
+	for _, opt := range opts {
+		ss = append(ss, fmt.Sprint(opt))
+	}
+	return fmt.Sprintf("Options{%s}", strings.Join(ss, ", "))
+}
+
+// FilterPath returns a new Option where opt is only evaluated if filter f
+// returns true for the current Path in the value tree.
+//
+// This filter is called even if a slice element or map entry is missing and
+// provides an opportunity to ignore such cases. The filter function must be
+// symmetric such that the filter result is identical regardless of whether the
+// missing value is from x or y.
+//
+// The option passed in may be an Ignore, Transformer, Comparer, Options, or
+// a previously filtered Option.
+func FilterPath(f func(Path) bool, opt Option) Option {
+	if f == nil {
+		panic("invalid path filter function")
+	}
+	if opt := normalizeOption(opt); opt != nil {
+		return &pathFilter{fnc: f, opt: opt}
+	}
+	return nil
+}
+
+type pathFilter struct {
+	core
+	fnc func(Path) bool
+	opt Option
+}
+
+func (f pathFilter) filter(s *state, t reflect.Type, vx, vy reflect.Value) applicableOption {
+	if f.fnc(s.curPath) {
+		return f.opt.filter(s, t, vx, vy)
+	}
+	return nil
+}
+
+func (f pathFilter) String() string {
+	return fmt.Sprintf("FilterPath(%s, %v)", function.NameOf(reflect.ValueOf(f.fnc)), f.opt)
+}
+
+// FilterValues returns a new Option where opt is only evaluated if filter f,
+// which is a function of the form "func(T, T) bool", returns true for the
+// current pair of values being compared. If either value is invalid or
+// the type of the values is not assignable to T, then this filter implicitly
+// returns false.
+//
+// The filter function must be
+// symmetric (i.e., agnostic to the order of the inputs) and
+// deterministic (i.e., produces the same result when given the same inputs).
+// If T is an interface, it is possible that f is called with two values with
+// different concrete types that both implement T.
+//
+// The option passed in may be an Ignore, Transformer, Comparer, Options, or
+// a previously filtered Option.
+func FilterValues(f interface{}, opt Option) Option {
+	v := reflect.ValueOf(f)
+	if !function.IsType(v.Type(), function.ValueFilter) || v.IsNil() {
+		panic(fmt.Sprintf("invalid values filter function: %T", f))
+	}
+	if opt := normalizeOption(opt); opt != nil {
+		vf := &valuesFilter{fnc: v, opt: opt}
+		if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+			vf.typ = ti
+		}
+		return vf
+	}
+	return nil
+}
+
+type valuesFilter struct {
+	core
+	typ reflect.Type  // T
+	fnc reflect.Value // func(T, T) bool
+	opt Option
+}
+
+func (f valuesFilter) filter(s *state, t reflect.Type, vx, vy reflect.Value) applicableOption {
+	if !vx.IsValid() || !vx.CanInterface() || !vy.IsValid() || !vy.CanInterface() {
+		return nil
+	}
+	if (f.typ == nil || t.AssignableTo(f.typ)) && s.callTTBFunc(f.fnc, vx, vy) {
+		return f.opt.filter(s, t, vx, vy)
+	}
+	return nil
+}
+
+func (f valuesFilter) String() string {
+	return fmt.Sprintf("FilterValues(%s, %v)", function.NameOf(f.fnc), f.opt)
+}
+
+// Ignore is an Option that causes all comparisons to be ignored.
+// This value is intended to be combined with FilterPath or FilterValues.
+// It is an error to pass an unfiltered Ignore option to Equal.
+func Ignore() Option { return ignore{} }
+
+type ignore struct{ core }
+
+func (ignore) isFiltered() bool                                                     { return false }
+func (ignore) filter(_ *state, _ reflect.Type, _, _ reflect.Value) applicableOption { return ignore{} }
+func (ignore) apply(s *state, _, _ reflect.Value)                                   { s.report(true, reportByIgnore) }
+func (ignore) String() string                                                       { return "Ignore()" }
+
+// validator is a sentinel Option type to indicate that some options could not
+// be evaluated due to unexported fields, missing slice elements, or
+// missing map entries. Both values are validator only for unexported fields.
+type validator struct{ core }
+
+func (validator) filter(_ *state, _ reflect.Type, vx, vy reflect.Value) applicableOption {
+	if !vx.IsValid() || !vy.IsValid() {
+		return validator{}
+	}
+	if !vx.CanInterface() || !vy.CanInterface() {
+		return validator{}
+	}
+	return nil
+}
+func (validator) apply(s *state, vx, vy reflect.Value) {
+	// Implies missing slice element or map entry.
+	if !vx.IsValid() || !vy.IsValid() {
+		s.report(vx.IsValid() == vy.IsValid(), 0)
+		return
+	}
+
+	// Unable to Interface implies unexported field without visibility access.
+	if !vx.CanInterface() || !vy.CanInterface() {
+		help := "consider using a custom Comparer; if you control the implementation of type, you can also consider using an Exporter, AllowUnexported, or cmpopts.IgnoreUnexported"
+		var name string
+		if t := s.curPath.Index(-2).Type(); t.Name() != "" {
+			// Named type with unexported fields.
+			name = fmt.Sprintf("%q.%v", t.PkgPath(), t.Name()) // e.g., "path/to/package".MyType
+			if _, ok := reflect.New(t).Interface().(error); ok {
+				help = "consider using cmpopts.EquateErrors to compare error values"
+			}
+		} else {
+			// Unnamed type with unexported fields. Derive PkgPath from field.
+			var pkgPath string
+			for i := 0; i < t.NumField() && pkgPath == ""; i++ {
+				pkgPath = t.Field(i).PkgPath
+			}
+			name = fmt.Sprintf("%q.(%v)", pkgPath, t.String()) // e.g., "path/to/package".(struct { a int })
+		}
+		panic(fmt.Sprintf("cannot handle unexported field at %#v:\n\t%v\n%s", s.curPath, name, help))
+	}
+
+	panic("not reachable")
+}
+
+// identRx represents a valid identifier according to the Go specification.
+const identRx = `[_\p{L}][_\p{L}\p{N}]*`
+
+var identsRx = regexp.MustCompile(`^` + identRx + `(\.` + identRx + `)*$`)
+
+// Transformer returns an Option that applies a transformation function that
+// converts values of a certain type into that of another.
+//
+// The transformer f must be a function "func(T) R" that converts values of
+// type T to those of type R and is implicitly filtered to input values
+// assignable to T. The transformer must not mutate T in any way.
+//
+// To help prevent some cases of infinite recursive cycles applying the
+// same transform to the output of itself (e.g., in the case where the
+// input and output types are the same), an implicit filter is added such that
+// a transformer is applicable only if that exact transformer is not already
+// in the tail of the Path since the last non-Transform step.
+// For situations where the implicit filter is still insufficient,
+// consider using cmpopts.AcyclicTransformer, which adds a filter
+// to prevent the transformer from being recursively applied upon itself.
+//
+// The name is a user provided label that is used as the Transform.Name in the
+// transformation PathStep (and eventually shown in the Diff output).
+// The name must be a valid identifier or qualified identifier in Go syntax.
+// If empty, an arbitrary name is used.
+func Transformer(name string, f interface{}) Option {
+	v := reflect.ValueOf(f)
+	if !function.IsType(v.Type(), function.Transformer) || v.IsNil() {
+		panic(fmt.Sprintf("invalid transformer function: %T", f))
+	}
+	if name == "" {
+		name = function.NameOf(v)
+		if !identsRx.MatchString(name) {
+			name = "λ" // Lambda-symbol as placeholder name
+		}
+	} else if !identsRx.MatchString(name) {
+		panic(fmt.Sprintf("invalid name: %q", name))
+	}
+	tr := &transformer{name: name, fnc: reflect.ValueOf(f)}
+	if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+		tr.typ = ti
+	}
+	return tr
+}
+
+type transformer struct {
+	core
+	name string
+	typ  reflect.Type  // T
+	fnc  reflect.Value // func(T) R
+}
+
+func (tr *transformer) isFiltered() bool { return tr.typ != nil }
+
+func (tr *transformer) filter(s *state, t reflect.Type, _, _ reflect.Value) applicableOption {
+	for i := len(s.curPath) - 1; i >= 0; i-- {
+		if t, ok := s.curPath[i].(Transform); !ok {
+			break // Hit most recent non-Transform step
+		} else if tr == t.trans {
+			return nil // Cannot directly use same Transform
+		}
+	}
+	if tr.typ == nil || t.AssignableTo(tr.typ) {
+		return tr
+	}
+	return nil
+}
+
+func (tr *transformer) apply(s *state, vx, vy reflect.Value) {
+	step := Transform{&transform{pathStep{typ: tr.fnc.Type().Out(0)}, tr}}
+	vvx := s.callTRFunc(tr.fnc, vx, step)
+	vvy := s.callTRFunc(tr.fnc, vy, step)
+	step.vx, step.vy = vvx, vvy
+	s.compareAny(step)
+}
+
+func (tr transformer) String() string {
+	return fmt.Sprintf("Transformer(%s, %s)", tr.name, function.NameOf(tr.fnc))
+}
+
+// Comparer returns an Option that determines whether two values are equal
+// to each other.
+//
+// The comparer f must be a function "func(T, T) bool" and is implicitly
+// filtered to input values assignable to T. If T is an interface, it is
+// possible that f is called with two values of different concrete types that
+// both implement T.
+//
+// The equality function must be:
+//	• Symmetric: equal(x, y) == equal(y, x)
+//	• Deterministic: equal(x, y) == equal(x, y)
+//	• Pure: equal(x, y) does not modify x or y
+func Comparer(f interface{}) Option {
+	v := reflect.ValueOf(f)
+	if !function.IsType(v.Type(), function.Equal) || v.IsNil() {
+		panic(fmt.Sprintf("invalid comparer function: %T", f))
+	}
+	cm := &comparer{fnc: v}
+	if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+		cm.typ = ti
+	}
+	return cm
+}
+
+type comparer struct {
+	core
+	typ reflect.Type  // T
+	fnc reflect.Value // func(T, T) bool
+}
+
+func (cm *comparer) isFiltered() bool { return cm.typ != nil }
+
+func (cm *comparer) filter(_ *state, t reflect.Type, _, _ reflect.Value) applicableOption {
+	if cm.typ == nil || t.AssignableTo(cm.typ) {
+		return cm
+	}
+	return nil
+}
+
+func (cm *comparer) apply(s *state, vx, vy reflect.Value) {
+	eq := s.callTTBFunc(cm.fnc, vx, vy)
+	s.report(eq, reportByFunc)
+}
+
+func (cm comparer) String() string {
+	return fmt.Sprintf("Comparer(%s)", function.NameOf(cm.fnc))
+}
+
+// Exporter returns an Option that specifies whether Equal is allowed to
+// introspect into the unexported fields of certain struct types.
+//
+// Users of this option must understand that comparing on unexported fields
+// from external packages is not safe since changes in the internal
+// implementation of some external package may cause the result of Equal
+// to unexpectedly change. However, it may be valid to use this option on types
+// defined in an internal package where the semantic meaning of an unexported
+// field is in the control of the user.
+//
+// In many cases, a custom Comparer should be used instead that defines
+// equality as a function of the public API of a type rather than the underlying
+// unexported implementation.
+//
+// For example, the reflect.Type documentation defines equality to be determined
+// by the == operator on the interface (essentially performing a shallow pointer
+// comparison) and most attempts to compare *regexp.Regexp types are interested
+// in only checking that the regular expression strings are equal.
+// Both of these are accomplished using Comparers:
+//
+//	Comparer(func(x, y reflect.Type) bool { return x == y })
+//	Comparer(func(x, y *regexp.Regexp) bool { return x.String() == y.String() })
+//
+// In other cases, the cmpopts.IgnoreUnexported option can be used to ignore
+// all unexported fields on specified struct types.
+func Exporter(f func(reflect.Type) bool) Option {
+	if !supportExporters {
+		panic("Exporter is not supported on purego builds")
+	}
+	return exporter(f)
+}
+
+type exporter func(reflect.Type) bool
+
+func (exporter) filter(_ *state, _ reflect.Type, _, _ reflect.Value) applicableOption {
+	panic("not implemented")
+}
+
+// AllowUnexported returns an Options that allows Equal to forcibly introspect
+// unexported fields of the specified struct types.
+//
+// See Exporter for the proper use of this option.
+func AllowUnexported(types ...interface{}) Option {
+	m := make(map[reflect.Type]bool)
+	for _, typ := range types {
+		t := reflect.TypeOf(typ)
+		if t.Kind() != reflect.Struct {
+			panic(fmt.Sprintf("invalid struct type: %T", typ))
+		}
+		m[t] = true
+	}
+	return exporter(func(t reflect.Type) bool { return m[t] })
+}
+
+// Result represents the comparison result for a single node and
+// is provided by cmp when calling Result (see Reporter).
+type Result struct {
+	_     [0]func() // Make Result incomparable
+	flags resultFlags
+}
+
+// Equal reports whether the node was determined to be equal or not.
+// As a special case, ignored nodes are considered equal.
+func (r Result) Equal() bool {
+	return r.flags&(reportEqual|reportByIgnore) != 0
+}
+
+// ByIgnore reports whether the node is equal because it was ignored.
+// This never reports true if Equal reports false.
+func (r Result) ByIgnore() bool {
+	return r.flags&reportByIgnore != 0
+}
+
+// ByMethod reports whether the Equal method determined equality.
+func (r Result) ByMethod() bool {
+	return r.flags&reportByMethod != 0
+}
+
+// ByFunc reports whether a Comparer function determined equality.
+func (r Result) ByFunc() bool {
+	return r.flags&reportByFunc != 0
+}
+
+// ByCycle reports whether a reference cycle was detected.
+func (r Result) ByCycle() bool {
+	return r.flags&reportByCycle != 0
+}
+
+type resultFlags uint
+
+const (
+	_ resultFlags = (1 << iota) / 2
+
+	reportEqual
+	reportUnequal
+	reportByIgnore
+	reportByMethod
+	reportByFunc
+	reportByCycle
+)
+
+// Reporter is an Option that can be passed to Equal. When Equal traverses
+// the value trees, it calls PushStep as it descends into each node in the
+// tree and PopStep as it ascend out of the node. The leaves of the tree are
+// either compared (determined to be equal or not equal) or ignored and reported
+// as such by calling the Report method.
+func Reporter(r interface {
+	// PushStep is called when a tree-traversal operation is performed.
+	// The PathStep itself is only valid until the step is popped.
+	// The PathStep.Values are valid for the duration of the entire traversal
+	// and must not be mutated.
+	//
+	// Equal always calls PushStep at the start to provide an operation-less
+	// PathStep used to report the root values.
+	//
+	// Within a slice, the exact set of inserted, removed, or modified elements
+	// is unspecified and may change in future implementations.
+	// The entries of a map are iterated through in an unspecified order.
+	PushStep(PathStep)
+
+	// Report is called exactly once on leaf nodes to report whether the
+	// comparison identified the node as equal, unequal, or ignored.
+	// A leaf node is one that is immediately preceded by and followed by
+	// a pair of PushStep and PopStep calls.
+	Report(Result)
+
+	// PopStep ascends back up the value tree.
+	// There is always a matching pop call for every push call.
+	PopStep()
+}) Option {
+	return reporter{r}
+}
+
+type reporter struct{ reporterIface }
+type reporterIface interface {
+	PushStep(PathStep)
+	Report(Result)
+	PopStep()
+}
+
+func (reporter) filter(_ *state, _ reflect.Type, _, _ reflect.Value) applicableOption {
+	panic("not implemented")
+}
+
+// normalizeOption normalizes the input options such that all Options groups
+// are flattened and groups with a single element are reduced to that element.
+// Only coreOptions and Options containing coreOptions are allowed.
+func normalizeOption(src Option) Option {
+	switch opts := flattenOptions(nil, Options{src}); len(opts) {
+	case 0:
+		return nil
+	case 1:
+		return opts[0]
+	default:
+		return opts
+	}
+}
+
+// flattenOptions copies all options in src to dst as a flat list.
+// Only coreOptions and Options containing coreOptions are allowed.
+func flattenOptions(dst, src Options) Options {
+	for _, opt := range src {
+		switch opt := opt.(type) {
+		case nil:
+			continue
+		case Options:
+			dst = flattenOptions(dst, opt)
+		case coreOption:
+			dst = append(dst, opt)
+		default:
+			panic(fmt.Sprintf("invalid option type: %T", opt))
+		}
+	}
+	return dst
+}

vendor/github.com/google/go-cmp/cmp/path.go

@@ -0,0 +1,378 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+// Path is a list of PathSteps describing the sequence of operations to get
+// from some root type to the current position in the value tree.
+// The first Path element is always an operation-less PathStep that exists
+// simply to identify the initial type.
+//
+// When traversing structs with embedded structs, the embedded struct will
+// always be accessed as a field before traversing the fields of the
+// embedded struct themselves. That is, an exported field from the
+// embedded struct will never be accessed directly from the parent struct.
+type Path []PathStep
+
+// PathStep is a union-type for specific operations to traverse
+// a value's tree structure. Users of this package never need to implement
+// these types as values of this type will be returned by this package.
+//
+// Implementations of this interface are
+// StructField, SliceIndex, MapIndex, Indirect, TypeAssertion, and Transform.
+type PathStep interface {
+	String() string
+
+	// Type is the resulting type after performing the path step.
+	Type() reflect.Type
+
+	// Values is the resulting values after performing the path step.
+	// The type of each valid value is guaranteed to be identical to Type.
+	//
+	// In some cases, one or both may be invalid or have restrictions:
+	//	• For StructField, both are not interface-able if the current field
+	//	is unexported and the struct type is not explicitly permitted by
+	//	an Exporter to traverse unexported fields.
+	//	• For SliceIndex, one may be invalid if an element is missing from
+	//	either the x or y slice.
+	//	• For MapIndex, one may be invalid if an entry is missing from
+	//	either the x or y map.
+	//
+	// The provided values must not be mutated.
+	Values() (vx, vy reflect.Value)
+}
+
+var (
+	_ PathStep = StructField{}
+	_ PathStep = SliceIndex{}
+	_ PathStep = MapIndex{}
+	_ PathStep = Indirect{}
+	_ PathStep = TypeAssertion{}
+	_ PathStep = Transform{}
+)
+
+func (pa *Path) push(s PathStep) {
+	*pa = append(*pa, s)
+}
+
+func (pa *Path) pop() {
+	*pa = (*pa)[:len(*pa)-1]
+}
+
+// Last returns the last PathStep in the Path.
+// If the path is empty, this returns a non-nil PathStep that reports a nil Type.
+func (pa Path) Last() PathStep {
+	return pa.Index(-1)
+}
+
+// Index returns the ith step in the Path and supports negative indexing.
+// A negative index starts counting from the tail of the Path such that -1
+// refers to the last step, -2 refers to the second-to-last step, and so on.
+// If index is invalid, this returns a non-nil PathStep that reports a nil Type.
+func (pa Path) Index(i int) PathStep {
+	if i < 0 {
+		i = len(pa) + i
+	}
+	if i < 0 || i >= len(pa) {
+		return pathStep{}
+	}
+	return pa[i]
+}
+
+// String returns the simplified path to a node.
+// The simplified path only contains struct field accesses.
+//
+// For example:
+//	MyMap.MySlices.MyField
+func (pa Path) String() string {
+	var ss []string
+	for _, s := range pa {
+		if _, ok := s.(StructField); ok {
+			ss = append(ss, s.String())
+		}
+	}
+	return strings.TrimPrefix(strings.Join(ss, ""), ".")
+}
+
+// GoString returns the path to a specific node using Go syntax.
+//
+// For example:
+//	(*root.MyMap["key"].(*mypkg.MyStruct).MySlices)[2][3].MyField
+func (pa Path) GoString() string {
+	var ssPre, ssPost []string
+	var numIndirect int
+	for i, s := range pa {
+		var nextStep PathStep
+		if i+1 < len(pa) {
+			nextStep = pa[i+1]
+		}
+		switch s := s.(type) {
+		case Indirect:
+			numIndirect++
+			pPre, pPost := "(", ")"
+			switch nextStep.(type) {
+			case Indirect:
+				continue // Next step is indirection, so let them batch up
+			case StructField:
+				numIndirect-- // Automatic indirection on struct fields
+			case nil:
+				pPre, pPost = "", "" // Last step; no need for parenthesis
+			}
+			if numIndirect > 0 {
+				ssPre = append(ssPre, pPre+strings.Repeat("*", numIndirect))
+				ssPost = append(ssPost, pPost)
+			}
+			numIndirect = 0
+			continue
+		case Transform:
+			ssPre = append(ssPre, s.trans.name+"(")
+			ssPost = append(ssPost, ")")
+			continue
+		}
+		ssPost = append(ssPost, s.String())
+	}
+	for i, j := 0, len(ssPre)-1; i < j; i, j = i+1, j-1 {
+		ssPre[i], ssPre[j] = ssPre[j], ssPre[i]
+	}
+	return strings.Join(ssPre, "") + strings.Join(ssPost, "")
+}
+
+type pathStep struct {
+	typ    reflect.Type
+	vx, vy reflect.Value
+}
+
+func (ps pathStep) Type() reflect.Type             { return ps.typ }
+func (ps pathStep) Values() (vx, vy reflect.Value) { return ps.vx, ps.vy }
+func (ps pathStep) String() string {
+	if ps.typ == nil {
+		return "<nil>"
+	}
+	s := ps.typ.String()
+	if s == "" || strings.ContainsAny(s, "{}\n") {
+		return "root" // Type too simple or complex to print
+	}
+	return fmt.Sprintf("{%s}", s)
+}
+
+// StructField represents a struct field access on a field called Name.
+type StructField struct{ *structField }
+type structField struct {
+	pathStep
+	name string
+	idx  int
+
+	// These fields are used for forcibly accessing an unexported field.
+	// pvx, pvy, and field are only valid if unexported is true.
+	unexported bool
+	mayForce   bool                // Forcibly allow visibility
+	paddr      bool                // Was parent addressable?
+	pvx, pvy   reflect.Value       // Parent values (always addressible)
+	field      reflect.StructField // Field information
+}
+
+func (sf StructField) Type() reflect.Type { return sf.typ }
+func (sf StructField) Values() (vx, vy reflect.Value) {
+	if !sf.unexported {
+		return sf.vx, sf.vy // CanInterface reports true
+	}
+
+	// Forcibly obtain read-write access to an unexported struct field.
+	if sf.mayForce {
+		vx = retrieveUnexportedField(sf.pvx, sf.field, sf.paddr)
+		vy = retrieveUnexportedField(sf.pvy, sf.field, sf.paddr)
+		return vx, vy // CanInterface reports true
+	}
+	return sf.vx, sf.vy // CanInterface reports false
+}
+func (sf StructField) String() string { return fmt.Sprintf(".%s", sf.name) }
+
+// Name is the field name.
+func (sf StructField) Name() string { return sf.name }
+
+// Index is the index of the field in the parent struct type.
+// See reflect.Type.Field.
+func (sf StructField) Index() int { return sf.idx }
+
+// SliceIndex is an index operation on a slice or array at some index Key.
+type SliceIndex struct{ *sliceIndex }
+type sliceIndex struct {
+	pathStep
+	xkey, ykey int
+	isSlice    bool // False for reflect.Array
+}
+
+func (si SliceIndex) Type() reflect.Type             { return si.typ }
+func (si SliceIndex) Values() (vx, vy reflect.Value) { return si.vx, si.vy }
+func (si SliceIndex) String() string {
+	switch {
+	case si.xkey == si.ykey:
+		return fmt.Sprintf("[%d]", si.xkey)
+	case si.ykey == -1:
+		// [5->?] means "I don't know where X[5] went"
+		return fmt.Sprintf("[%d->?]", si.xkey)
+	case si.xkey == -1:
+		// [?->3] means "I don't know where Y[3] came from"
+		return fmt.Sprintf("[?->%d]", si.ykey)
+	default:
+		// [5->3] means "X[5] moved to Y[3]"
+		return fmt.Sprintf("[%d->%d]", si.xkey, si.ykey)
+	}
+}
+
+// Key is the index key; it may return -1 if in a split state
+func (si SliceIndex) Key() int {
+	if si.xkey != si.ykey {
+		return -1
+	}
+	return si.xkey
+}
+
+// SplitKeys are the indexes for indexing into slices in the
+// x and y values, respectively. These indexes may differ due to the
+// insertion or removal of an element in one of the slices, causing
+// all of the indexes to be shifted. If an index is -1, then that
+// indicates that the element does not exist in the associated slice.
+//
+// Key is guaranteed to return -1 if and only if the indexes returned
+// by SplitKeys are not the same. SplitKeys will never return -1 for
+// both indexes.
+func (si SliceIndex) SplitKeys() (ix, iy int) { return si.xkey, si.ykey }
+
+// MapIndex is an index operation on a map at some index Key.
+type MapIndex struct{ *mapIndex }
+type mapIndex struct {
+	pathStep
+	key reflect.Value
+}
+
+func (mi MapIndex) Type() reflect.Type             { return mi.typ }
+func (mi MapIndex) Values() (vx, vy reflect.Value) { return mi.vx, mi.vy }
+func (mi MapIndex) String() string                 { return fmt.Sprintf("[%#v]", mi.key) }
+
+// Key is the value of the map key.
+func (mi MapIndex) Key() reflect.Value { return mi.key }
+
+// Indirect represents pointer indirection on the parent type.
+type Indirect struct{ *indirect }
+type indirect struct {
+	pathStep
+}
+
+func (in Indirect) Type() reflect.Type             { return in.typ }
+func (in Indirect) Values() (vx, vy reflect.Value) { return in.vx, in.vy }
+func (in Indirect) String() string                 { return "*" }
+
+// TypeAssertion represents a type assertion on an interface.
+type TypeAssertion struct{ *typeAssertion }
+type typeAssertion struct {
+	pathStep
+}
+
+func (ta TypeAssertion) Type() reflect.Type             { return ta.typ }
+func (ta TypeAssertion) Values() (vx, vy reflect.Value) { return ta.vx, ta.vy }
+func (ta TypeAssertion) String() string                 { return fmt.Sprintf(".(%v)", ta.typ) }
+
+// Transform is a transformation from the parent type to the current type.
+type Transform struct{ *transform }
+type transform struct {
+	pathStep
+	trans *transformer
+}
+
+func (tf Transform) Type() reflect.Type             { return tf.typ }
+func (tf Transform) Values() (vx, vy reflect.Value) { return tf.vx, tf.vy }
+func (tf Transform) String() string                 { return fmt.Sprintf("%s()", tf.trans.name) }
+
+// Name is the name of the Transformer.
+func (tf Transform) Name() string { return tf.trans.name }
+
+// Func is the function pointer to the transformer function.
+func (tf Transform) Func() reflect.Value { return tf.trans.fnc }
+
+// Option returns the originally constructed Transformer option.
+// The == operator can be used to detect the exact option used.
+func (tf Transform) Option() Option { return tf.trans }
+
+// pointerPath represents a dual-stack of pointers encountered when
+// recursively traversing the x and y values. This data structure supports
+// detection of cycles and determining whether the cycles are equal.
+// In Go, cycles can occur via pointers, slices, and maps.
+//
+// The pointerPath uses a map to represent a stack; where descension into a
+// pointer pushes the address onto the stack, and ascension from a pointer
+// pops the address from the stack. Thus, when traversing into a pointer from
+// reflect.Ptr, reflect.Slice element, or reflect.Map, we can detect cycles
+// by checking whether the pointer has already been visited. The cycle detection
+// uses a separate stack for the x and y values.
+//
+// If a cycle is detected we need to determine whether the two pointers
+// should be considered equal. The definition of equality chosen by Equal
+// requires two graphs to have the same structure. To determine this, both the
+// x and y values must have a cycle where the previous pointers were also
+// encountered together as a pair.
+//
+// Semantically, this is equivalent to augmenting Indirect, SliceIndex, and
+// MapIndex with pointer information for the x and y values.
+// Suppose px and py are two pointers to compare, we then search the
+// Path for whether px was ever encountered in the Path history of x, and
+// similarly so with py. If either side has a cycle, the comparison is only
+// equal if both px and py have a cycle resulting from the same PathStep.
+//
+// Using a map as a stack is more performant as we can perform cycle detection
+// in O(1) instead of O(N) where N is len(Path).
+type pointerPath struct {
+	// mx is keyed by x pointers, where the value is the associated y pointer.
+	mx map[value.Pointer]value.Pointer
+	// my is keyed by y pointers, where the value is the associated x pointer.
+	my map[value.Pointer]value.Pointer
+}
+
+func (p *pointerPath) Init() {
+	p.mx = make(map[value.Pointer]value.Pointer)
+	p.my = make(map[value.Pointer]value.Pointer)
+}
+
+// Push indicates intent to descend into pointers vx and vy where
+// visited reports whether either has been seen before. If visited before,
+// equal reports whether both pointers were encountered together.
+// Pop must be called if and only if the pointers were never visited.
+//
+// The pointers vx and vy must be a reflect.Ptr, reflect.Slice, or reflect.Map
+// and be non-nil.
+func (p pointerPath) Push(vx, vy reflect.Value) (equal, visited bool) {
+	px := value.PointerOf(vx)
+	py := value.PointerOf(vy)
+	_, ok1 := p.mx[px]
+	_, ok2 := p.my[py]
+	if ok1 || ok2 {
+		equal = p.mx[px] == py && p.my[py] == px // Pointers paired together
+		return equal, true
+	}
+	p.mx[px] = py
+	p.my[py] = px
+	return false, false
+}
+
+// Pop ascends from pointers vx and vy.
+func (p pointerPath) Pop(vx, vy reflect.Value) {
+	delete(p.mx, value.PointerOf(vx))
+	delete(p.my, value.PointerOf(vy))
+}
+
+// isExported reports whether the identifier is exported.
+func isExported(id string) bool {
+	r, _ := utf8.DecodeRuneInString(id)
+	return unicode.IsUpper(r)
+}

vendor/github.com/google/go-cmp/cmp/report.go

@@ -0,0 +1,54 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+// defaultReporter implements the reporter interface.
+//
+// As Equal serially calls the PushStep, Report, and PopStep methods, the
+// defaultReporter constructs a tree-based representation of the compared value
+// and the result of each comparison (see valueNode).
+//
+// When the String method is called, the FormatDiff method transforms the
+// valueNode tree into a textNode tree, which is a tree-based representation
+// of the textual output (see textNode).
+//
+// Lastly, the textNode.String method produces the final report as a string.
+type defaultReporter struct {
+	root *valueNode
+	curr *valueNode
+}
+
+func (r *defaultReporter) PushStep(ps PathStep) {
+	r.curr = r.curr.PushStep(ps)
+	if r.root == nil {
+		r.root = r.curr
+	}
+}
+func (r *defaultReporter) Report(rs Result) {
+	r.curr.Report(rs)
+}
+func (r *defaultReporter) PopStep() {
+	r.curr = r.curr.PopStep()
+}
+
+// String provides a full report of the differences detected as a structured
+// literal in pseudo-Go syntax. String may only be called after the entire tree
+// has been traversed.
+func (r *defaultReporter) String() string {
+	assert(r.root != nil && r.curr == nil)
+	if r.root.NumDiff == 0 {
+		return ""
+	}
+	ptrs := new(pointerReferences)
+	text := formatOptions{}.FormatDiff(r.root, ptrs)
+	resolveReferences(text)
+	return text.String()
+}
+
+func assert(ok bool) {
+	if !ok {
+		panic("assertion failure")
+	}
+}

vendor/github.com/google/go-cmp/cmp/report_compare.go

@@ -0,0 +1,432 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+// numContextRecords is the number of surrounding equal records to print.
+const numContextRecords = 2
+
+type diffMode byte
+
+const (
+	diffUnknown   diffMode = 0
+	diffIdentical diffMode = ' '
+	diffRemoved   diffMode = '-'
+	diffInserted  diffMode = '+'
+)
+
+type typeMode int
+
+const (
+	// emitType always prints the type.
+	emitType typeMode = iota
+	// elideType never prints the type.
+	elideType
+	// autoType prints the type only for composite kinds
+	// (i.e., structs, slices, arrays, and maps).
+	autoType
+)
+
+type formatOptions struct {
+	// DiffMode controls the output mode of FormatDiff.
+	//
+	// If diffUnknown,   then produce a diff of the x and y values.
+	// If diffIdentical, then emit values as if they were equal.
+	// If diffRemoved,   then only emit x values (ignoring y values).
+	// If diffInserted,  then only emit y values (ignoring x values).
+	DiffMode diffMode
+
+	// TypeMode controls whether to print the type for the current node.
+	//
+	// As a general rule of thumb, we always print the type of the next node
+	// after an interface, and always elide the type of the next node after
+	// a slice or map node.
+	TypeMode typeMode
+
+	// formatValueOptions are options specific to printing reflect.Values.
+	formatValueOptions
+}
+
+func (opts formatOptions) WithDiffMode(d diffMode) formatOptions {
+	opts.DiffMode = d
+	return opts
+}
+func (opts formatOptions) WithTypeMode(t typeMode) formatOptions {
+	opts.TypeMode = t
+	return opts
+}
+func (opts formatOptions) WithVerbosity(level int) formatOptions {
+	opts.VerbosityLevel = level
+	opts.LimitVerbosity = true
+	return opts
+}
+func (opts formatOptions) verbosity() uint {
+	switch {
+	case opts.VerbosityLevel < 0:
+		return 0
+	case opts.VerbosityLevel > 16:
+		return 16 // some reasonable maximum to avoid shift overflow
+	default:
+		return uint(opts.VerbosityLevel)
+	}
+}
+
+const maxVerbosityPreset = 6
+
+// verbosityPreset modifies the verbosity settings given an index
+// between 0 and maxVerbosityPreset, inclusive.
+func verbosityPreset(opts formatOptions, i int) formatOptions {
+	opts.VerbosityLevel = int(opts.verbosity()) + 2*i
+	if i > 0 {
+		opts.AvoidStringer = true
+	}
+	if i >= maxVerbosityPreset {
+		opts.PrintAddresses = true
+		opts.QualifiedNames = true
+	}
+	return opts
+}
+
+// FormatDiff converts a valueNode tree into a textNode tree, where the later
+// is a textual representation of the differences detected in the former.
+func (opts formatOptions) FormatDiff(v *valueNode, ptrs *pointerReferences) (out textNode) {
+	if opts.DiffMode == diffIdentical {
+		opts = opts.WithVerbosity(1)
+	} else if opts.verbosity() < 3 {
+		opts = opts.WithVerbosity(3)
+	}
+
+	// Check whether we have specialized formatting for this node.
+	// This is not necessary, but helpful for producing more readable outputs.
+	if opts.CanFormatDiffSlice(v) {
+		return opts.FormatDiffSlice(v)
+	}
+
+	var parentKind reflect.Kind
+	if v.parent != nil && v.parent.TransformerName == "" {
+		parentKind = v.parent.Type.Kind()
+	}
+
+	// For leaf nodes, format the value based on the reflect.Values alone.
+	if v.MaxDepth == 0 {
+		switch opts.DiffMode {
+		case diffUnknown, diffIdentical:
+			// Format Equal.
+			if v.NumDiff == 0 {
+				outx := opts.FormatValue(v.ValueX, parentKind, ptrs)
+				outy := opts.FormatValue(v.ValueY, parentKind, ptrs)
+				if v.NumIgnored > 0 && v.NumSame == 0 {
+					return textEllipsis
+				} else if outx.Len() < outy.Len() {
+					return outx
+				} else {
+					return outy
+				}
+			}
+
+			// Format unequal.
+			assert(opts.DiffMode == diffUnknown)
+			var list textList
+			outx := opts.WithTypeMode(elideType).FormatValue(v.ValueX, parentKind, ptrs)
+			outy := opts.WithTypeMode(elideType).FormatValue(v.ValueY, parentKind, ptrs)
+			for i := 0; i <= maxVerbosityPreset && outx != nil && outy != nil && outx.Equal(outy); i++ {
+				opts2 := verbosityPreset(opts, i).WithTypeMode(elideType)
+				outx = opts2.FormatValue(v.ValueX, parentKind, ptrs)
+				outy = opts2.FormatValue(v.ValueY, parentKind, ptrs)
+			}
+			if outx != nil {
+				list = append(list, textRecord{Diff: '-', Value: outx})
+			}
+			if outy != nil {
+				list = append(list, textRecord{Diff: '+', Value: outy})
+			}
+			return opts.WithTypeMode(emitType).FormatType(v.Type, list)
+		case diffRemoved:
+			return opts.FormatValue(v.ValueX, parentKind, ptrs)
+		case diffInserted:
+			return opts.FormatValue(v.ValueY, parentKind, ptrs)
+		default:
+			panic("invalid diff mode")
+		}
+	}
+
+	// Register slice element to support cycle detection.
+	if parentKind == reflect.Slice {
+		ptrRefs := ptrs.PushPair(v.ValueX, v.ValueY, opts.DiffMode, true)
+		defer ptrs.Pop()
+		defer func() { out = wrapTrunkReferences(ptrRefs, out) }()
+	}
+
+	// Descend into the child value node.
+	if v.TransformerName != "" {
+		out := opts.WithTypeMode(emitType).FormatDiff(v.Value, ptrs)
+		out = &textWrap{Prefix: "Inverse(" + v.TransformerName + ", ", Value: out, Suffix: ")"}
+		return opts.FormatType(v.Type, out)
+	} else {
+		switch k := v.Type.Kind(); k {
+		case reflect.Struct, reflect.Array, reflect.Slice:
+			out = opts.formatDiffList(v.Records, k, ptrs)
+			out = opts.FormatType(v.Type, out)
+		case reflect.Map:
+			// Register map to support cycle detection.
+			ptrRefs := ptrs.PushPair(v.ValueX, v.ValueY, opts.DiffMode, false)
+			defer ptrs.Pop()
+
+			out = opts.formatDiffList(v.Records, k, ptrs)
+			out = wrapTrunkReferences(ptrRefs, out)
+			out = opts.FormatType(v.Type, out)
+		case reflect.Ptr:
+			// Register pointer to support cycle detection.
+			ptrRefs := ptrs.PushPair(v.ValueX, v.ValueY, opts.DiffMode, false)
+			defer ptrs.Pop()
+
+			out = opts.FormatDiff(v.Value, ptrs)
+			out = wrapTrunkReferences(ptrRefs, out)
+			out = &textWrap{Prefix: "&", Value: out}
+		case reflect.Interface:
+			out = opts.WithTypeMode(emitType).FormatDiff(v.Value, ptrs)
+		default:
+			panic(fmt.Sprintf("%v cannot have children", k))
+		}
+		return out
+	}
+}
+
+func (opts formatOptions) formatDiffList(recs []reportRecord, k reflect.Kind, ptrs *pointerReferences) textNode {
+	// Derive record name based on the data structure kind.
+	var name string
+	var formatKey func(reflect.Value) string
+	switch k {
+	case reflect.Struct:
+		name = "field"
+		opts = opts.WithTypeMode(autoType)
+		formatKey = func(v reflect.Value) string { return v.String() }
+	case reflect.Slice, reflect.Array:
+		name = "element"
+		opts = opts.WithTypeMode(elideType)
+		formatKey = func(reflect.Value) string { return "" }
+	case reflect.Map:
+		name = "entry"
+		opts = opts.WithTypeMode(elideType)
+		formatKey = func(v reflect.Value) string { return formatMapKey(v, false, ptrs) }
+	}
+
+	maxLen := -1
+	if opts.LimitVerbosity {
+		if opts.DiffMode == diffIdentical {
+			maxLen = ((1 << opts.verbosity()) >> 1) << 2 // 0, 4, 8, 16, 32, etc...
+		} else {
+			maxLen = (1 << opts.verbosity()) << 1 // 2, 4, 8, 16, 32, 64, etc...
+		}
+		opts.VerbosityLevel--
+	}
+
+	// Handle unification.
+	switch opts.DiffMode {
+	case diffIdentical, diffRemoved, diffInserted:
+		var list textList
+		var deferredEllipsis bool // Add final "..." to indicate records were dropped
+		for _, r := range recs {
+			if len(list) == maxLen {
+				deferredEllipsis = true
+				break
+			}
+
+			// Elide struct fields that are zero value.
+			if k == reflect.Struct {
+				var isZero bool
+				switch opts.DiffMode {
+				case diffIdentical:
+					isZero = value.IsZero(r.Value.ValueX) || value.IsZero(r.Value.ValueY)
+				case diffRemoved:
+					isZero = value.IsZero(r.Value.ValueX)
+				case diffInserted:
+					isZero = value.IsZero(r.Value.ValueY)
+				}
+				if isZero {
+					continue
+				}
+			}
+			// Elide ignored nodes.
+			if r.Value.NumIgnored > 0 && r.Value.NumSame+r.Value.NumDiff == 0 {
+				deferredEllipsis = !(k == reflect.Slice || k == reflect.Array)
+				if !deferredEllipsis {
+					list.AppendEllipsis(diffStats{})
+				}
+				continue
+			}
+			if out := opts.FormatDiff(r.Value, ptrs); out != nil {
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+			}
+		}
+		if deferredEllipsis {
+			list.AppendEllipsis(diffStats{})
+		}
+		return &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+	case diffUnknown:
+	default:
+		panic("invalid diff mode")
+	}
+
+	// Handle differencing.
+	var numDiffs int
+	var list textList
+	var keys []reflect.Value // invariant: len(list) == len(keys)
+	groups := coalesceAdjacentRecords(name, recs)
+	maxGroup := diffStats{Name: name}
+	for i, ds := range groups {
+		if maxLen >= 0 && numDiffs >= maxLen {
+			maxGroup = maxGroup.Append(ds)
+			continue
+		}
+
+		// Handle equal records.
+		if ds.NumDiff() == 0 {
+			// Compute the number of leading and trailing records to print.
+			var numLo, numHi int
+			numEqual := ds.NumIgnored + ds.NumIdentical
+			for numLo < numContextRecords && numLo+numHi < numEqual && i != 0 {
+				if r := recs[numLo].Value; r.NumIgnored > 0 && r.NumSame+r.NumDiff == 0 {
+					break
+				}
+				numLo++
+			}
+			for numHi < numContextRecords && numLo+numHi < numEqual && i != len(groups)-1 {
+				if r := recs[numEqual-numHi-1].Value; r.NumIgnored > 0 && r.NumSame+r.NumDiff == 0 {
+					break
+				}
+				numHi++
+			}
+			if numEqual-(numLo+numHi) == 1 && ds.NumIgnored == 0 {
+				numHi++ // Avoid pointless coalescing of a single equal record
+			}
+
+			// Format the equal values.
+			for _, r := range recs[:numLo] {
+				out := opts.WithDiffMode(diffIdentical).FormatDiff(r.Value, ptrs)
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+				keys = append(keys, r.Key)
+			}
+			if numEqual > numLo+numHi {
+				ds.NumIdentical -= numLo + numHi
+				list.AppendEllipsis(ds)
+				for len(keys) < len(list) {
+					keys = append(keys, reflect.Value{})
+				}
+			}
+			for _, r := range recs[numEqual-numHi : numEqual] {
+				out := opts.WithDiffMode(diffIdentical).FormatDiff(r.Value, ptrs)
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+				keys = append(keys, r.Key)
+			}
+			recs = recs[numEqual:]
+			continue
+		}
+
+		// Handle unequal records.
+		for _, r := range recs[:ds.NumDiff()] {
+			switch {
+			case opts.CanFormatDiffSlice(r.Value):
+				out := opts.FormatDiffSlice(r.Value)
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+				keys = append(keys, r.Key)
+			case r.Value.NumChildren == r.Value.MaxDepth:
+				outx := opts.WithDiffMode(diffRemoved).FormatDiff(r.Value, ptrs)
+				outy := opts.WithDiffMode(diffInserted).FormatDiff(r.Value, ptrs)
+				for i := 0; i <= maxVerbosityPreset && outx != nil && outy != nil && outx.Equal(outy); i++ {
+					opts2 := verbosityPreset(opts, i)
+					outx = opts2.WithDiffMode(diffRemoved).FormatDiff(r.Value, ptrs)
+					outy = opts2.WithDiffMode(diffInserted).FormatDiff(r.Value, ptrs)
+				}
+				if outx != nil {
+					list = append(list, textRecord{Diff: diffRemoved, Key: formatKey(r.Key), Value: outx})
+					keys = append(keys, r.Key)
+				}
+				if outy != nil {
+					list = append(list, textRecord{Diff: diffInserted, Key: formatKey(r.Key), Value: outy})
+					keys = append(keys, r.Key)
+				}
+			default:
+				out := opts.FormatDiff(r.Value, ptrs)
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+				keys = append(keys, r.Key)
+			}
+		}
+		recs = recs[ds.NumDiff():]
+		numDiffs += ds.NumDiff()
+	}
+	if maxGroup.IsZero() {
+		assert(len(recs) == 0)
+	} else {
+		list.AppendEllipsis(maxGroup)
+		for len(keys) < len(list) {
+			keys = append(keys, reflect.Value{})
+		}
+	}
+	assert(len(list) == len(keys))
+
+	// For maps, the default formatting logic uses fmt.Stringer which may
+	// produce ambiguous output. Avoid calling String to disambiguate.
+	if k == reflect.Map {
+		var ambiguous bool
+		seenKeys := map[string]reflect.Value{}
+		for i, currKey := range keys {
+			if currKey.IsValid() {
+				strKey := list[i].Key
+				prevKey, seen := seenKeys[strKey]
+				if seen && prevKey.CanInterface() && currKey.CanInterface() {
+					ambiguous = prevKey.Interface() != currKey.Interface()
+					if ambiguous {
+						break
+					}
+				}
+				seenKeys[strKey] = currKey
+			}
+		}
+		if ambiguous {
+			for i, k := range keys {
+				if k.IsValid() {
+					list[i].Key = formatMapKey(k, true, ptrs)
+				}
+			}
+		}
+	}
+
+	return &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+}
+
+// coalesceAdjacentRecords coalesces the list of records into groups of
+// adjacent equal, or unequal counts.
+func coalesceAdjacentRecords(name string, recs []reportRecord) (groups []diffStats) {
+	var prevCase int // Arbitrary index into which case last occurred
+	lastStats := func(i int) *diffStats {
+		if prevCase != i {
+			groups = append(groups, diffStats{Name: name})
+			prevCase = i
+		}
+		return &groups[len(groups)-1]
+	}
+	for _, r := range recs {
+		switch rv := r.Value; {
+		case rv.NumIgnored > 0 && rv.NumSame+rv.NumDiff == 0:
+			lastStats(1).NumIgnored++
+		case rv.NumDiff == 0:
+			lastStats(1).NumIdentical++
+		case rv.NumDiff > 0 && !rv.ValueY.IsValid():
+			lastStats(2).NumRemoved++
+		case rv.NumDiff > 0 && !rv.ValueX.IsValid():
+			lastStats(2).NumInserted++
+		default:
+			lastStats(2).NumModified++
+		}
+	}
+	return groups
+}

vendor/github.com/google/go-cmp/cmp/report_references.go

@@ -0,0 +1,264 @@
+// Copyright 2020, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+
+	"github.com/google/go-cmp/cmp/internal/flags"
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+const (
+	pointerDelimPrefix = "⟪"
+	pointerDelimSuffix = "⟫"
+)
+
+// formatPointer prints the address of the pointer.
+func formatPointer(p value.Pointer, withDelims bool) string {
+	v := p.Uintptr()
+	if flags.Deterministic {
+		v = 0xdeadf00f // Only used for stable testing purposes
+	}
+	if withDelims {
+		return pointerDelimPrefix + formatHex(uint64(v)) + pointerDelimSuffix
+	}
+	return formatHex(uint64(v))
+}
+
+// pointerReferences is a stack of pointers visited so far.
+type pointerReferences [][2]value.Pointer
+
+func (ps *pointerReferences) PushPair(vx, vy reflect.Value, d diffMode, deref bool) (pp [2]value.Pointer) {
+	if deref && vx.IsValid() {
+		vx = vx.Addr()
+	}
+	if deref && vy.IsValid() {
+		vy = vy.Addr()
+	}
+	switch d {
+	case diffUnknown, diffIdentical:
+		pp = [2]value.Pointer{value.PointerOf(vx), value.PointerOf(vy)}
+	case diffRemoved:
+		pp = [2]value.Pointer{value.PointerOf(vx), value.Pointer{}}
+	case diffInserted:
+		pp = [2]value.Pointer{value.Pointer{}, value.PointerOf(vy)}
+	}
+	*ps = append(*ps, pp)
+	return pp
+}
+
+func (ps *pointerReferences) Push(v reflect.Value) (p value.Pointer, seen bool) {
+	p = value.PointerOf(v)
+	for _, pp := range *ps {
+		if p == pp[0] || p == pp[1] {
+			return p, true
+		}
+	}
+	*ps = append(*ps, [2]value.Pointer{p, p})
+	return p, false
+}
+
+func (ps *pointerReferences) Pop() {
+	*ps = (*ps)[:len(*ps)-1]
+}
+
+// trunkReferences is metadata for a textNode indicating that the sub-tree
+// represents the value for either pointer in a pair of references.
+type trunkReferences struct{ pp [2]value.Pointer }
+
+// trunkReference is metadata for a textNode indicating that the sub-tree
+// represents the value for the given pointer reference.
+type trunkReference struct{ p value.Pointer }
+
+// leafReference is metadata for a textNode indicating that the value is
+// truncated as it refers to another part of the tree (i.e., a trunk).
+type leafReference struct{ p value.Pointer }
+
+func wrapTrunkReferences(pp [2]value.Pointer, s textNode) textNode {
+	switch {
+	case pp[0].IsNil():
+		return &textWrap{Value: s, Metadata: trunkReference{pp[1]}}
+	case pp[1].IsNil():
+		return &textWrap{Value: s, Metadata: trunkReference{pp[0]}}
+	case pp[0] == pp[1]:
+		return &textWrap{Value: s, Metadata: trunkReference{pp[0]}}
+	default:
+		return &textWrap{Value: s, Metadata: trunkReferences{pp}}
+	}
+}
+func wrapTrunkReference(p value.Pointer, printAddress bool, s textNode) textNode {
+	var prefix string
+	if printAddress {
+		prefix = formatPointer(p, true)
+	}
+	return &textWrap{Prefix: prefix, Value: s, Metadata: trunkReference{p}}
+}
+func makeLeafReference(p value.Pointer, printAddress bool) textNode {
+	out := &textWrap{Prefix: "(", Value: textEllipsis, Suffix: ")"}
+	var prefix string
+	if printAddress {
+		prefix = formatPointer(p, true)
+	}
+	return &textWrap{Prefix: prefix, Value: out, Metadata: leafReference{p}}
+}
+
+// resolveReferences walks the textNode tree searching for any leaf reference
+// metadata and resolves each against the corresponding trunk references.
+// Since pointer addresses in memory are not particularly readable to the user,
+// it replaces each pointer value with an arbitrary and unique reference ID.
+func resolveReferences(s textNode) {
+	var walkNodes func(textNode, func(textNode))
+	walkNodes = func(s textNode, f func(textNode)) {
+		f(s)
+		switch s := s.(type) {
+		case *textWrap:
+			walkNodes(s.Value, f)
+		case textList:
+			for _, r := range s {
+				walkNodes(r.Value, f)
+			}
+		}
+	}
+
+	// Collect all trunks and leaves with reference metadata.
+	var trunks, leaves []*textWrap
+	walkNodes(s, func(s textNode) {
+		if s, ok := s.(*textWrap); ok {
+			switch s.Metadata.(type) {
+			case leafReference:
+				leaves = append(leaves, s)
+			case trunkReference, trunkReferences:
+				trunks = append(trunks, s)
+			}
+		}
+	})
+
+	// No leaf references to resolve.
+	if len(leaves) == 0 {
+		return
+	}
+
+	// Collect the set of all leaf references to resolve.
+	leafPtrs := make(map[value.Pointer]bool)
+	for _, leaf := range leaves {
+		leafPtrs[leaf.Metadata.(leafReference).p] = true
+	}
+
+	// Collect the set of trunk pointers that are always paired together.
+	// This allows us to assign a single ID to both pointers for brevity.
+	// If a pointer in a pair ever occurs by itself or as a different pair,
+	// then the pair is broken.
+	pairedTrunkPtrs := make(map[value.Pointer]value.Pointer)
+	unpair := func(p value.Pointer) {
+		if !pairedTrunkPtrs[p].IsNil() {
+			pairedTrunkPtrs[pairedTrunkPtrs[p]] = value.Pointer{} // invalidate other half
+		}
+		pairedTrunkPtrs[p] = value.Pointer{} // invalidate this half
+	}
+	for _, trunk := range trunks {
+		switch p := trunk.Metadata.(type) {
+		case trunkReference:
+			unpair(p.p) // standalone pointer cannot be part of a pair
+		case trunkReferences:
+			p0, ok0 := pairedTrunkPtrs[p.pp[0]]
+			p1, ok1 := pairedTrunkPtrs[p.pp[1]]
+			switch {
+			case !ok0 && !ok1:
+				// Register the newly seen pair.
+				pairedTrunkPtrs[p.pp[0]] = p.pp[1]
+				pairedTrunkPtrs[p.pp[1]] = p.pp[0]
+			case ok0 && ok1 && p0 == p.pp[1] && p1 == p.pp[0]:
+				// Exact pair already seen; do nothing.
+			default:
+				// Pair conflicts with some other pair; break all pairs.
+				unpair(p.pp[0])
+				unpair(p.pp[1])
+			}
+		}
+	}
+
+	// Correlate each pointer referenced by leaves to a unique identifier,
+	// and print the IDs for each trunk that matches those pointers.
+	var nextID uint
+	ptrIDs := make(map[value.Pointer]uint)
+	newID := func() uint {
+		id := nextID
+		nextID++
+		return id
+	}
+	for _, trunk := range trunks {
+		switch p := trunk.Metadata.(type) {
+		case trunkReference:
+			if print := leafPtrs[p.p]; print {
+				id, ok := ptrIDs[p.p]
+				if !ok {
+					id = newID()
+					ptrIDs[p.p] = id
+				}
+				trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id))
+			}
+		case trunkReferences:
+			print0 := leafPtrs[p.pp[0]]
+			print1 := leafPtrs[p.pp[1]]
+			if print0 || print1 {
+				id0, ok0 := ptrIDs[p.pp[0]]
+				id1, ok1 := ptrIDs[p.pp[1]]
+				isPair := pairedTrunkPtrs[p.pp[0]] == p.pp[1] && pairedTrunkPtrs[p.pp[1]] == p.pp[0]
+				if isPair {
+					var id uint
+					assert(ok0 == ok1) // must be seen together or not at all
+					if ok0 {
+						assert(id0 == id1) // must have the same ID
+						id = id0
+					} else {
+						id = newID()
+						ptrIDs[p.pp[0]] = id
+						ptrIDs[p.pp[1]] = id
+					}
+					trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id))
+				} else {
+					if print0 && !ok0 {
+						id0 = newID()
+						ptrIDs[p.pp[0]] = id0
+					}
+					if print1 && !ok1 {
+						id1 = newID()
+						ptrIDs[p.pp[1]] = id1
+					}
+					switch {
+					case print0 && print1:
+						trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id0)+","+formatReference(id1))
+					case print0:
+						trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id0))
+					case print1:
+						trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id1))
+					}
+				}
+			}
+		}
+	}
+
+	// Update all leaf references with the unique identifier.
+	for _, leaf := range leaves {
+		if id, ok := ptrIDs[leaf.Metadata.(leafReference).p]; ok {
+			leaf.Prefix = updateReferencePrefix(leaf.Prefix, formatReference(id))
+		}
+	}
+}
+
+func formatReference(id uint) string {
+	return fmt.Sprintf("ref#%d", id)
+}
+
+func updateReferencePrefix(prefix, ref string) string {
+	if prefix == "" {
+		return pointerDelimPrefix + ref + pointerDelimSuffix
+	}
+	suffix := strings.TrimPrefix(prefix, pointerDelimPrefix)
+	return pointerDelimPrefix + ref + ": " + suffix
+}

vendor/github.com/google/go-cmp/cmp/report_reflect.go

@@ -0,0 +1,402 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"bytes"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+type formatValueOptions struct {
+	// AvoidStringer controls whether to avoid calling custom stringer
+	// methods like error.Error or fmt.Stringer.String.
+	AvoidStringer bool
+
+	// PrintAddresses controls whether to print the address of all pointers,
+	// slice elements, and maps.
+	PrintAddresses bool
+
+	// QualifiedNames controls whether FormatType uses the fully qualified name
+	// (including the full package path as opposed to just the package name).
+	QualifiedNames bool
+
+	// VerbosityLevel controls the amount of output to produce.
+	// A higher value produces more output. A value of zero or lower produces
+	// no output (represented using an ellipsis).
+	// If LimitVerbosity is false, then the level is treated as infinite.
+	VerbosityLevel int
+
+	// LimitVerbosity specifies that formatting should respect VerbosityLevel.
+	LimitVerbosity bool
+}
+
+// FormatType prints the type as if it were wrapping s.
+// This may return s as-is depending on the current type and TypeMode mode.
+func (opts formatOptions) FormatType(t reflect.Type, s textNode) textNode {
+	// Check whether to emit the type or not.
+	switch opts.TypeMode {
+	case autoType:
+		switch t.Kind() {
+		case reflect.Struct, reflect.Slice, reflect.Array, reflect.Map:
+			if s.Equal(textNil) {
+				return s
+			}
+		default:
+			return s
+		}
+		if opts.DiffMode == diffIdentical {
+			return s // elide type for identical nodes
+		}
+	case elideType:
+		return s
+	}
+
+	// Determine the type label, applying special handling for unnamed types.
+	typeName := value.TypeString(t, opts.QualifiedNames)
+	if t.Name() == "" {
+		// According to Go grammar, certain type literals contain symbols that
+		// do not strongly bind to the next lexicographical token (e.g., *T).
+		switch t.Kind() {
+		case reflect.Chan, reflect.Func, reflect.Ptr:
+			typeName = "(" + typeName + ")"
+		}
+	}
+	return &textWrap{Prefix: typeName, Value: wrapParens(s)}
+}
+
+// wrapParens wraps s with a set of parenthesis, but avoids it if the
+// wrapped node itself is already surrounded by a pair of parenthesis or braces.
+// It handles unwrapping one level of pointer-reference nodes.
+func wrapParens(s textNode) textNode {
+	var refNode *textWrap
+	if s2, ok := s.(*textWrap); ok {
+		// Unwrap a single pointer reference node.
+		switch s2.Metadata.(type) {
+		case leafReference, trunkReference, trunkReferences:
+			refNode = s2
+			if s3, ok := refNode.Value.(*textWrap); ok {
+				s2 = s3
+			}
+		}
+
+		// Already has delimiters that make parenthesis unnecessary.
+		hasParens := strings.HasPrefix(s2.Prefix, "(") && strings.HasSuffix(s2.Suffix, ")")
+		hasBraces := strings.HasPrefix(s2.Prefix, "{") && strings.HasSuffix(s2.Suffix, "}")
+		if hasParens || hasBraces {
+			return s
+		}
+	}
+	if refNode != nil {
+		refNode.Value = &textWrap{Prefix: "(", Value: refNode.Value, Suffix: ")"}
+		return s
+	}
+	return &textWrap{Prefix: "(", Value: s, Suffix: ")"}
+}
+
+// FormatValue prints the reflect.Value, taking extra care to avoid descending
+// into pointers already in ptrs. As pointers are visited, ptrs is also updated.
+func (opts formatOptions) FormatValue(v reflect.Value, parentKind reflect.Kind, ptrs *pointerReferences) (out textNode) {
+	if !v.IsValid() {
+		return nil
+	}
+	t := v.Type()
+
+	// Check slice element for cycles.
+	if parentKind == reflect.Slice {
+		ptrRef, visited := ptrs.Push(v.Addr())
+		if visited {
+			return makeLeafReference(ptrRef, false)
+		}
+		defer ptrs.Pop()
+		defer func() { out = wrapTrunkReference(ptrRef, false, out) }()
+	}
+
+	// Check whether there is an Error or String method to call.
+	if !opts.AvoidStringer && v.CanInterface() {
+		// Avoid calling Error or String methods on nil receivers since many
+		// implementations crash when doing so.
+		if (t.Kind() != reflect.Ptr && t.Kind() != reflect.Interface) || !v.IsNil() {
+			var prefix, strVal string
+			func() {
+				// Swallow and ignore any panics from String or Error.
+				defer func() { recover() }()
+				switch v := v.Interface().(type) {
+				case error:
+					strVal = v.Error()
+					prefix = "e"
+				case fmt.Stringer:
+					strVal = v.String()
+					prefix = "s"
+				}
+			}()
+			if prefix != "" {
+				return opts.formatString(prefix, strVal)
+			}
+		}
+	}
+
+	// Check whether to explicitly wrap the result with the type.
+	var skipType bool
+	defer func() {
+		if !skipType {
+			out = opts.FormatType(t, out)
+		}
+	}()
+
+	switch t.Kind() {
+	case reflect.Bool:
+		return textLine(fmt.Sprint(v.Bool()))
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return textLine(fmt.Sprint(v.Int()))
+	case reflect.Uint, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return textLine(fmt.Sprint(v.Uint()))
+	case reflect.Uint8:
+		if parentKind == reflect.Slice || parentKind == reflect.Array {
+			return textLine(formatHex(v.Uint()))
+		}
+		return textLine(fmt.Sprint(v.Uint()))
+	case reflect.Uintptr:
+		return textLine(formatHex(v.Uint()))
+	case reflect.Float32, reflect.Float64:
+		return textLine(fmt.Sprint(v.Float()))
+	case reflect.Complex64, reflect.Complex128:
+		return textLine(fmt.Sprint(v.Complex()))
+	case reflect.String:
+		return opts.formatString("", v.String())
+	case reflect.UnsafePointer, reflect.Chan, reflect.Func:
+		return textLine(formatPointer(value.PointerOf(v), true))
+	case reflect.Struct:
+		var list textList
+		v := makeAddressable(v) // needed for retrieveUnexportedField
+		maxLen := v.NumField()
+		if opts.LimitVerbosity {
+			maxLen = ((1 << opts.verbosity()) >> 1) << 2 // 0, 4, 8, 16, 32, etc...
+			opts.VerbosityLevel--
+		}
+		for i := 0; i < v.NumField(); i++ {
+			vv := v.Field(i)
+			if value.IsZero(vv) {
+				continue // Elide fields with zero values
+			}
+			if len(list) == maxLen {
+				list.AppendEllipsis(diffStats{})
+				break
+			}
+			sf := t.Field(i)
+			if supportExporters && !isExported(sf.Name) {
+				vv = retrieveUnexportedField(v, sf, true)
+			}
+			s := opts.WithTypeMode(autoType).FormatValue(vv, t.Kind(), ptrs)
+			list = append(list, textRecord{Key: sf.Name, Value: s})
+		}
+		return &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+	case reflect.Slice:
+		if v.IsNil() {
+			return textNil
+		}
+
+		// Check whether this is a []byte of text data.
+		if t.Elem() == reflect.TypeOf(byte(0)) {
+			b := v.Bytes()
+			isPrintSpace := func(r rune) bool { return unicode.IsPrint(r) && unicode.IsSpace(r) }
+			if len(b) > 0 && utf8.Valid(b) && len(bytes.TrimFunc(b, isPrintSpace)) == 0 {
+				out = opts.formatString("", string(b))
+				return opts.WithTypeMode(emitType).FormatType(t, out)
+			}
+		}
+
+		fallthrough
+	case reflect.Array:
+		maxLen := v.Len()
+		if opts.LimitVerbosity {
+			maxLen = ((1 << opts.verbosity()) >> 1) << 2 // 0, 4, 8, 16, 32, etc...
+			opts.VerbosityLevel--
+		}
+		var list textList
+		for i := 0; i < v.Len(); i++ {
+			if len(list) == maxLen {
+				list.AppendEllipsis(diffStats{})
+				break
+			}
+			s := opts.WithTypeMode(elideType).FormatValue(v.Index(i), t.Kind(), ptrs)
+			list = append(list, textRecord{Value: s})
+		}
+
+		out = &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+		if t.Kind() == reflect.Slice && opts.PrintAddresses {
+			header := fmt.Sprintf("ptr:%v, len:%d, cap:%d", formatPointer(value.PointerOf(v), false), v.Len(), v.Cap())
+			out = &textWrap{Prefix: pointerDelimPrefix + header + pointerDelimSuffix, Value: out}
+		}
+		return out
+	case reflect.Map:
+		if v.IsNil() {
+			return textNil
+		}
+
+		// Check pointer for cycles.
+		ptrRef, visited := ptrs.Push(v)
+		if visited {
+			return makeLeafReference(ptrRef, opts.PrintAddresses)
+		}
+		defer ptrs.Pop()
+
+		maxLen := v.Len()
+		if opts.LimitVerbosity {
+			maxLen = ((1 << opts.verbosity()) >> 1) << 2 // 0, 4, 8, 16, 32, etc...
+			opts.VerbosityLevel--
+		}
+		var list textList
+		for _, k := range value.SortKeys(v.MapKeys()) {
+			if len(list) == maxLen {
+				list.AppendEllipsis(diffStats{})
+				break
+			}
+			sk := formatMapKey(k, false, ptrs)
+			sv := opts.WithTypeMode(elideType).FormatValue(v.MapIndex(k), t.Kind(), ptrs)
+			list = append(list, textRecord{Key: sk, Value: sv})
+		}
+
+		out = &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+		out = wrapTrunkReference(ptrRef, opts.PrintAddresses, out)
+		return out
+	case reflect.Ptr:
+		if v.IsNil() {
+			return textNil
+		}
+
+		// Check pointer for cycles.
+		ptrRef, visited := ptrs.Push(v)
+		if visited {
+			out = makeLeafReference(ptrRef, opts.PrintAddresses)
+			return &textWrap{Prefix: "&", Value: out}
+		}
+		defer ptrs.Pop()
+
+		skipType = true // Let the underlying value print the type instead
+		out = opts.FormatValue(v.Elem(), t.Kind(), ptrs)
+		out = wrapTrunkReference(ptrRef, opts.PrintAddresses, out)
+		out = &textWrap{Prefix: "&", Value: out}
+		return out
+	case reflect.Interface:
+		if v.IsNil() {
+			return textNil
+		}
+		// Interfaces accept different concrete types,
+		// so configure the underlying value to explicitly print the type.
+		skipType = true // Print the concrete type instead
+		return opts.WithTypeMode(emitType).FormatValue(v.Elem(), t.Kind(), ptrs)
+	default:
+		panic(fmt.Sprintf("%v kind not handled", v.Kind()))
+	}
+}
+
+func (opts formatOptions) formatString(prefix, s string) textNode {
+	maxLen := len(s)
+	maxLines := strings.Count(s, "\n") + 1
+	if opts.LimitVerbosity {
+		maxLen = (1 << opts.verbosity()) << 5   // 32, 64, 128, 256, etc...
+		maxLines = (1 << opts.verbosity()) << 2 //  4, 8, 16, 32, 64, etc...
+	}
+
+	// For multiline strings, use the triple-quote syntax,
+	// but only use it when printing removed or inserted nodes since
+	// we only want the extra verbosity for those cases.
+	lines := strings.Split(strings.TrimSuffix(s, "\n"), "\n")
+	isTripleQuoted := len(lines) >= 4 && (opts.DiffMode == '-' || opts.DiffMode == '+')
+	for i := 0; i < len(lines) && isTripleQuoted; i++ {
+		lines[i] = strings.TrimPrefix(strings.TrimSuffix(lines[i], "\r"), "\r") // trim leading/trailing carriage returns for legacy Windows endline support
+		isPrintable := func(r rune) bool {
+			return unicode.IsPrint(r) || r == '\t' // specially treat tab as printable
+		}
+		line := lines[i]
+		isTripleQuoted = !strings.HasPrefix(strings.TrimPrefix(line, prefix), `"""`) && !strings.HasPrefix(line, "...") && strings.TrimFunc(line, isPrintable) == "" && len(line) <= maxLen
+	}
+	if isTripleQuoted {
+		var list textList
+		list = append(list, textRecord{Diff: opts.DiffMode, Value: textLine(prefix + `"""`), ElideComma: true})
+		for i, line := range lines {
+			if numElided := len(lines) - i; i == maxLines-1 && numElided > 1 {
+				comment := commentString(fmt.Sprintf("%d elided lines", numElided))
+				list = append(list, textRecord{Diff: opts.DiffMode, Value: textEllipsis, ElideComma: true, Comment: comment})
+				break
+			}
+			list = append(list, textRecord{Diff: opts.DiffMode, Value: textLine(line), ElideComma: true})
+		}
+		list = append(list, textRecord{Diff: opts.DiffMode, Value: textLine(prefix + `"""`), ElideComma: true})
+		return &textWrap{Prefix: "(", Value: list, Suffix: ")"}
+	}
+
+	// Format the string as a single-line quoted string.
+	if len(s) > maxLen+len(textEllipsis) {
+		return textLine(prefix + formatString(s[:maxLen]) + string(textEllipsis))
+	}
+	return textLine(prefix + formatString(s))
+}
+
+// formatMapKey formats v as if it were a map key.
+// The result is guaranteed to be a single line.
+func formatMapKey(v reflect.Value, disambiguate bool, ptrs *pointerReferences) string {
+	var opts formatOptions
+	opts.DiffMode = diffIdentical
+	opts.TypeMode = elideType
+	opts.PrintAddresses = disambiguate
+	opts.AvoidStringer = disambiguate
+	opts.QualifiedNames = disambiguate
+	opts.VerbosityLevel = maxVerbosityPreset
+	opts.LimitVerbosity = true
+	s := opts.FormatValue(v, reflect.Map, ptrs).String()
+	return strings.TrimSpace(s)
+}
+
+// formatString prints s as a double-quoted or backtick-quoted string.
+func formatString(s string) string {
+	// Use quoted string if it the same length as a raw string literal.
+	// Otherwise, attempt to use the raw string form.
+	qs := strconv.Quote(s)
+	if len(qs) == 1+len(s)+1 {
+		return qs
+	}
+
+	// Disallow newlines to ensure output is a single line.
+	// Only allow printable runes for readability purposes.
+	rawInvalid := func(r rune) bool {
+		return r == '`' || r == '\n' || !(unicode.IsPrint(r) || r == '\t')
+	}
+	if utf8.ValidString(s) && strings.IndexFunc(s, rawInvalid) < 0 {
+		return "`" + s + "`"
+	}
+	return qs
+}
+
+// formatHex prints u as a hexadecimal integer in Go notation.
+func formatHex(u uint64) string {
+	var f string
+	switch {
+	case u <= 0xff:
+		f = "0x%02x"
+	case u <= 0xffff:
+		f = "0x%04x"
+	case u <= 0xffffff:
+		f = "0x%06x"
+	case u <= 0xffffffff:
+		f = "0x%08x"
+	case u <= 0xffffffffff:
+		f = "0x%010x"
+	case u <= 0xffffffffffff:
+		f = "0x%012x"
+	case u <= 0xffffffffffffff:
+		f = "0x%014x"
+	case u <= 0xffffffffffffffff:
+		f = "0x%016x"
+	}
+	return fmt.Sprintf(f, u)
+}

vendor/github.com/google/go-cmp/cmp/report_slices.go

@@ -0,0 +1,613 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"bytes"
+	"fmt"
+	"math"
+	"reflect"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp/internal/diff"
+)
+
+// CanFormatDiffSlice reports whether we support custom formatting for nodes
+// that are slices of primitive kinds or strings.
+func (opts formatOptions) CanFormatDiffSlice(v *valueNode) bool {
+	switch {
+	case opts.DiffMode != diffUnknown:
+		return false // Must be formatting in diff mode
+	case v.NumDiff == 0:
+		return false // No differences detected
+	case !v.ValueX.IsValid() || !v.ValueY.IsValid():
+		return false // Both values must be valid
+	case v.NumIgnored > 0:
+		return false // Some ignore option was used
+	case v.NumTransformed > 0:
+		return false // Some transform option was used
+	case v.NumCompared > 1:
+		return false // More than one comparison was used
+	case v.NumCompared == 1 && v.Type.Name() != "":
+		// The need for cmp to check applicability of options on every element
+		// in a slice is a significant performance detriment for large []byte.
+		// The workaround is to specify Comparer(bytes.Equal),
+		// which enables cmp to compare []byte more efficiently.
+		// If they differ, we still want to provide batched diffing.
+		// The logic disallows named types since they tend to have their own
+		// String method, with nicer formatting than what this provides.
+		return false
+	}
+
+	// Check whether this is an interface with the same concrete types.
+	t := v.Type
+	vx, vy := v.ValueX, v.ValueY
+	if t.Kind() == reflect.Interface && !vx.IsNil() && !vy.IsNil() && vx.Elem().Type() == vy.Elem().Type() {
+		vx, vy = vx.Elem(), vy.Elem()
+		t = vx.Type()
+	}
+
+	// Check whether we provide specialized diffing for this type.
+	switch t.Kind() {
+	case reflect.String:
+	case reflect.Array, reflect.Slice:
+		// Only slices of primitive types have specialized handling.
+		switch t.Elem().Kind() {
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+			reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr,
+			reflect.Bool, reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
+		default:
+			return false
+		}
+
+		// Both slice values have to be non-empty.
+		if t.Kind() == reflect.Slice && (vx.Len() == 0 || vy.Len() == 0) {
+			return false
+		}
+
+		// If a sufficient number of elements already differ,
+		// use specialized formatting even if length requirement is not met.
+		if v.NumDiff > v.NumSame {
+			return true
+		}
+	default:
+		return false
+	}
+
+	// Use specialized string diffing for longer slices or strings.
+	const minLength = 64
+	return vx.Len() >= minLength && vy.Len() >= minLength
+}
+
+// FormatDiffSlice prints a diff for the slices (or strings) represented by v.
+// This provides custom-tailored logic to make printing of differences in
+// textual strings and slices of primitive kinds more readable.
+func (opts formatOptions) FormatDiffSlice(v *valueNode) textNode {
+	assert(opts.DiffMode == diffUnknown)
+	t, vx, vy := v.Type, v.ValueX, v.ValueY
+	if t.Kind() == reflect.Interface {
+		vx, vy = vx.Elem(), vy.Elem()
+		t = vx.Type()
+		opts = opts.WithTypeMode(emitType)
+	}
+
+	// Auto-detect the type of the data.
+	var sx, sy string
+	var ssx, ssy []string
+	var isString, isMostlyText, isPureLinedText, isBinary bool
+	switch {
+	case t.Kind() == reflect.String:
+		sx, sy = vx.String(), vy.String()
+		isString = true
+	case t.Kind() == reflect.Slice && t.Elem() == reflect.TypeOf(byte(0)):
+		sx, sy = string(vx.Bytes()), string(vy.Bytes())
+		isString = true
+	case t.Kind() == reflect.Array:
+		// Arrays need to be addressable for slice operations to work.
+		vx2, vy2 := reflect.New(t).Elem(), reflect.New(t).Elem()
+		vx2.Set(vx)
+		vy2.Set(vy)
+		vx, vy = vx2, vy2
+	}
+	if isString {
+		var numTotalRunes, numValidRunes, numLines, lastLineIdx, maxLineLen int
+		for i, r := range sx + sy {
+			numTotalRunes++
+			if (unicode.IsPrint(r) || unicode.IsSpace(r)) && r != utf8.RuneError {
+				numValidRunes++
+			}
+			if r == '\n' {
+				if maxLineLen < i-lastLineIdx {
+					maxLineLen = i - lastLineIdx
+				}
+				lastLineIdx = i + 1
+				numLines++
+			}
+		}
+		isPureText := numValidRunes == numTotalRunes
+		isMostlyText = float64(numValidRunes) > math.Floor(0.90*float64(numTotalRunes))
+		isPureLinedText = isPureText && numLines >= 4 && maxLineLen <= 1024
+		isBinary = !isMostlyText
+
+		// Avoid diffing by lines if it produces a significantly more complex
+		// edit script than diffing by bytes.
+		if isPureLinedText {
+			ssx = strings.Split(sx, "\n")
+			ssy = strings.Split(sy, "\n")
+			esLines := diff.Difference(len(ssx), len(ssy), func(ix, iy int) diff.Result {
+				return diff.BoolResult(ssx[ix] == ssy[iy])
+			})
+			esBytes := diff.Difference(len(sx), len(sy), func(ix, iy int) diff.Result {
+				return diff.BoolResult(sx[ix] == sy[iy])
+			})
+			efficiencyLines := float64(esLines.Dist()) / float64(len(esLines))
+			efficiencyBytes := float64(esBytes.Dist()) / float64(len(esBytes))
+			isPureLinedText = efficiencyLines < 4*efficiencyBytes
+		}
+	}
+
+	// Format the string into printable records.
+	var list textList
+	var delim string
+	switch {
+	// If the text appears to be multi-lined text,
+	// then perform differencing across individual lines.
+	case isPureLinedText:
+		list = opts.formatDiffSlice(
+			reflect.ValueOf(ssx), reflect.ValueOf(ssy), 1, "line",
+			func(v reflect.Value, d diffMode) textRecord {
+				s := formatString(v.Index(0).String())
+				return textRecord{Diff: d, Value: textLine(s)}
+			},
+		)
+		delim = "\n"
+
+		// If possible, use a custom triple-quote (""") syntax for printing
+		// differences in a string literal. This format is more readable,
+		// but has edge-cases where differences are visually indistinguishable.
+		// This format is avoided under the following conditions:
+		//	• A line starts with `"""`
+		//	• A line starts with "..."
+		//	• A line contains non-printable characters
+		//	• Adjacent different lines differ only by whitespace
+		//
+		// For example:
+		//		"""
+		//		... // 3 identical lines
+		//		foo
+		//		bar
+		//	-	baz
+		//	+	BAZ
+		//		"""
+		isTripleQuoted := true
+		prevRemoveLines := map[string]bool{}
+		prevInsertLines := map[string]bool{}
+		var list2 textList
+		list2 = append(list2, textRecord{Value: textLine(`"""`), ElideComma: true})
+		for _, r := range list {
+			if !r.Value.Equal(textEllipsis) {
+				line, _ := strconv.Unquote(string(r.Value.(textLine)))
+				line = strings.TrimPrefix(strings.TrimSuffix(line, "\r"), "\r") // trim leading/trailing carriage returns for legacy Windows endline support
+				normLine := strings.Map(func(r rune) rune {
+					if unicode.IsSpace(r) {
+						return -1 // drop whitespace to avoid visually indistinguishable output
+					}
+					return r
+				}, line)
+				isPrintable := func(r rune) bool {
+					return unicode.IsPrint(r) || r == '\t' // specially treat tab as printable
+				}
+				isTripleQuoted = !strings.HasPrefix(line, `"""`) && !strings.HasPrefix(line, "...") && strings.TrimFunc(line, isPrintable) == ""
+				switch r.Diff {
+				case diffRemoved:
+					isTripleQuoted = isTripleQuoted && !prevInsertLines[normLine]
+					prevRemoveLines[normLine] = true
+				case diffInserted:
+					isTripleQuoted = isTripleQuoted && !prevRemoveLines[normLine]
+					prevInsertLines[normLine] = true
+				}
+				if !isTripleQuoted {
+					break
+				}
+				r.Value = textLine(line)
+				r.ElideComma = true
+			}
+			if !(r.Diff == diffRemoved || r.Diff == diffInserted) { // start a new non-adjacent difference group
+				prevRemoveLines = map[string]bool{}
+				prevInsertLines = map[string]bool{}
+			}
+			list2 = append(list2, r)
+		}
+		if r := list2[len(list2)-1]; r.Diff == diffIdentical && len(r.Value.(textLine)) == 0 {
+			list2 = list2[:len(list2)-1] // elide single empty line at the end
+		}
+		list2 = append(list2, textRecord{Value: textLine(`"""`), ElideComma: true})
+		if isTripleQuoted {
+			var out textNode = &textWrap{Prefix: "(", Value: list2, Suffix: ")"}
+			switch t.Kind() {
+			case reflect.String:
+				if t != reflect.TypeOf(string("")) {
+					out = opts.FormatType(t, out)
+				}
+			case reflect.Slice:
+				// Always emit type for slices since the triple-quote syntax
+				// looks like a string (not a slice).
+				opts = opts.WithTypeMode(emitType)
+				out = opts.FormatType(t, out)
+			}
+			return out
+		}
+
+	// If the text appears to be single-lined text,
+	// then perform differencing in approximately fixed-sized chunks.
+	// The output is printed as quoted strings.
+	case isMostlyText:
+		list = opts.formatDiffSlice(
+			reflect.ValueOf(sx), reflect.ValueOf(sy), 64, "byte",
+			func(v reflect.Value, d diffMode) textRecord {
+				s := formatString(v.String())
+				return textRecord{Diff: d, Value: textLine(s)}
+			},
+		)
+
+	// If the text appears to be binary data,
+	// then perform differencing in approximately fixed-sized chunks.
+	// The output is inspired by hexdump.
+	case isBinary:
+		list = opts.formatDiffSlice(
+			reflect.ValueOf(sx), reflect.ValueOf(sy), 16, "byte",
+			func(v reflect.Value, d diffMode) textRecord {
+				var ss []string
+				for i := 0; i < v.Len(); i++ {
+					ss = append(ss, formatHex(v.Index(i).Uint()))
+				}
+				s := strings.Join(ss, ", ")
+				comment := commentString(fmt.Sprintf("%c|%v|", d, formatASCII(v.String())))
+				return textRecord{Diff: d, Value: textLine(s), Comment: comment}
+			},
+		)
+
+	// For all other slices of primitive types,
+	// then perform differencing in approximately fixed-sized chunks.
+	// The size of each chunk depends on the width of the element kind.
+	default:
+		var chunkSize int
+		if t.Elem().Kind() == reflect.Bool {
+			chunkSize = 16
+		} else {
+			switch t.Elem().Bits() {
+			case 8:
+				chunkSize = 16
+			case 16:
+				chunkSize = 12
+			case 32:
+				chunkSize = 8
+			default:
+				chunkSize = 8
+			}
+		}
+		list = opts.formatDiffSlice(
+			vx, vy, chunkSize, t.Elem().Kind().String(),
+			func(v reflect.Value, d diffMode) textRecord {
+				var ss []string
+				for i := 0; i < v.Len(); i++ {
+					switch t.Elem().Kind() {
+					case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+						ss = append(ss, fmt.Sprint(v.Index(i).Int()))
+					case reflect.Uint, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+						ss = append(ss, fmt.Sprint(v.Index(i).Uint()))
+					case reflect.Uint8, reflect.Uintptr:
+						ss = append(ss, formatHex(v.Index(i).Uint()))
+					case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
+						ss = append(ss, fmt.Sprint(v.Index(i).Interface()))
+					}
+				}
+				s := strings.Join(ss, ", ")
+				return textRecord{Diff: d, Value: textLine(s)}
+			},
+		)
+	}
+
+	// Wrap the output with appropriate type information.
+	var out textNode = &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+	if !isMostlyText {
+		// The "{...}" byte-sequence literal is not valid Go syntax for strings.
+		// Emit the type for extra clarity (e.g. "string{...}").
+		if t.Kind() == reflect.String {
+			opts = opts.WithTypeMode(emitType)
+		}
+		return opts.FormatType(t, out)
+	}
+	switch t.Kind() {
+	case reflect.String:
+		out = &textWrap{Prefix: "strings.Join(", Value: out, Suffix: fmt.Sprintf(", %q)", delim)}
+		if t != reflect.TypeOf(string("")) {
+			out = opts.FormatType(t, out)
+		}
+	case reflect.Slice:
+		out = &textWrap{Prefix: "bytes.Join(", Value: out, Suffix: fmt.Sprintf(", %q)", delim)}
+		if t != reflect.TypeOf([]byte(nil)) {
+			out = opts.FormatType(t, out)
+		}
+	}
+	return out
+}
+
+// formatASCII formats s as an ASCII string.
+// This is useful for printing binary strings in a semi-legible way.
+func formatASCII(s string) string {
+	b := bytes.Repeat([]byte{'.'}, len(s))
+	for i := 0; i < len(s); i++ {
+		if ' ' <= s[i] && s[i] <= '~' {
+			b[i] = s[i]
+		}
+	}
+	return string(b)
+}
+
+func (opts formatOptions) formatDiffSlice(
+	vx, vy reflect.Value, chunkSize int, name string,
+	makeRec func(reflect.Value, diffMode) textRecord,
+) (list textList) {
+	eq := func(ix, iy int) bool {
+		return vx.Index(ix).Interface() == vy.Index(iy).Interface()
+	}
+	es := diff.Difference(vx.Len(), vy.Len(), func(ix, iy int) diff.Result {
+		return diff.BoolResult(eq(ix, iy))
+	})
+
+	appendChunks := func(v reflect.Value, d diffMode) int {
+		n0 := v.Len()
+		for v.Len() > 0 {
+			n := chunkSize
+			if n > v.Len() {
+				n = v.Len()
+			}
+			list = append(list, makeRec(v.Slice(0, n), d))
+			v = v.Slice(n, v.Len())
+		}
+		return n0 - v.Len()
+	}
+
+	var numDiffs int
+	maxLen := -1
+	if opts.LimitVerbosity {
+		maxLen = (1 << opts.verbosity()) << 2 // 4, 8, 16, 32, 64, etc...
+		opts.VerbosityLevel--
+	}
+
+	groups := coalesceAdjacentEdits(name, es)
+	groups = coalesceInterveningIdentical(groups, chunkSize/4)
+	groups = cleanupSurroundingIdentical(groups, eq)
+	maxGroup := diffStats{Name: name}
+	for i, ds := range groups {
+		if maxLen >= 0 && numDiffs >= maxLen {
+			maxGroup = maxGroup.Append(ds)
+			continue
+		}
+
+		// Print equal.
+		if ds.NumDiff() == 0 {
+			// Compute the number of leading and trailing equal bytes to print.
+			var numLo, numHi int
+			numEqual := ds.NumIgnored + ds.NumIdentical
+			for numLo < chunkSize*numContextRecords && numLo+numHi < numEqual && i != 0 {
+				numLo++
+			}
+			for numHi < chunkSize*numContextRecords && numLo+numHi < numEqual && i != len(groups)-1 {
+				numHi++
+			}
+			if numEqual-(numLo+numHi) <= chunkSize && ds.NumIgnored == 0 {
+				numHi = numEqual - numLo // Avoid pointless coalescing of single equal row
+			}
+
+			// Print the equal bytes.
+			appendChunks(vx.Slice(0, numLo), diffIdentical)
+			if numEqual > numLo+numHi {
+				ds.NumIdentical -= numLo + numHi
+				list.AppendEllipsis(ds)
+			}
+			appendChunks(vx.Slice(numEqual-numHi, numEqual), diffIdentical)
+			vx = vx.Slice(numEqual, vx.Len())
+			vy = vy.Slice(numEqual, vy.Len())
+			continue
+		}
+
+		// Print unequal.
+		len0 := len(list)
+		nx := appendChunks(vx.Slice(0, ds.NumIdentical+ds.NumRemoved+ds.NumModified), diffRemoved)
+		vx = vx.Slice(nx, vx.Len())
+		ny := appendChunks(vy.Slice(0, ds.NumIdentical+ds.NumInserted+ds.NumModified), diffInserted)
+		vy = vy.Slice(ny, vy.Len())
+		numDiffs += len(list) - len0
+	}
+	if maxGroup.IsZero() {
+		assert(vx.Len() == 0 && vy.Len() == 0)
+	} else {
+		list.AppendEllipsis(maxGroup)
+	}
+	return list
+}
+
+// coalesceAdjacentEdits coalesces the list of edits into groups of adjacent
+// equal or unequal counts.
+//
+// Example:
+//
+//	Input:  "..XXY...Y"
+//	Output: [
+//		{NumIdentical: 2},
+//		{NumRemoved: 2, NumInserted 1},
+//		{NumIdentical: 3},
+//		{NumInserted: 1},
+//	]
+//
+func coalesceAdjacentEdits(name string, es diff.EditScript) (groups []diffStats) {
+	var prevMode byte
+	lastStats := func(mode byte) *diffStats {
+		if prevMode != mode {
+			groups = append(groups, diffStats{Name: name})
+			prevMode = mode
+		}
+		return &groups[len(groups)-1]
+	}
+	for _, e := range es {
+		switch e {
+		case diff.Identity:
+			lastStats('=').NumIdentical++
+		case diff.UniqueX:
+			lastStats('!').NumRemoved++
+		case diff.UniqueY:
+			lastStats('!').NumInserted++
+		case diff.Modified:
+			lastStats('!').NumModified++
+		}
+	}
+	return groups
+}
+
+// coalesceInterveningIdentical coalesces sufficiently short (<= windowSize)
+// equal groups into adjacent unequal groups that currently result in a
+// dual inserted/removed printout. This acts as a high-pass filter to smooth
+// out high-frequency changes within the windowSize.
+//
+// Example:
+//
+//	WindowSize: 16,
+//	Input: [
+//		{NumIdentical: 61},              // group 0
+//		{NumRemoved: 3, NumInserted: 1}, // group 1
+//		{NumIdentical: 6},               // ├── coalesce
+//		{NumInserted: 2},                // ├── coalesce
+//		{NumIdentical: 1},               // ├── coalesce
+//		{NumRemoved: 9},                 // └── coalesce
+//		{NumIdentical: 64},              // group 2
+//		{NumRemoved: 3, NumInserted: 1}, // group 3
+//		{NumIdentical: 6},               // ├── coalesce
+//		{NumInserted: 2},                // ├── coalesce
+//		{NumIdentical: 1},               // ├── coalesce
+//		{NumRemoved: 7},                 // ├── coalesce
+//		{NumIdentical: 1},               // ├── coalesce
+//		{NumRemoved: 2},                 // └── coalesce
+//		{NumIdentical: 63},              // group 4
+//	]
+//	Output: [
+//		{NumIdentical: 61},
+//		{NumIdentical: 7, NumRemoved: 12, NumInserted: 3},
+//		{NumIdentical: 64},
+//		{NumIdentical: 8, NumRemoved: 12, NumInserted: 3},
+//		{NumIdentical: 63},
+//	]
+//
+func coalesceInterveningIdentical(groups []diffStats, windowSize int) []diffStats {
+	groups, groupsOrig := groups[:0], groups
+	for i, ds := range groupsOrig {
+		if len(groups) >= 2 && ds.NumDiff() > 0 {
+			prev := &groups[len(groups)-2] // Unequal group
+			curr := &groups[len(groups)-1] // Equal group
+			next := &groupsOrig[i]         // Unequal group
+			hadX, hadY := prev.NumRemoved > 0, prev.NumInserted > 0
+			hasX, hasY := next.NumRemoved > 0, next.NumInserted > 0
+			if ((hadX || hasX) && (hadY || hasY)) && curr.NumIdentical <= windowSize {
+				*prev = prev.Append(*curr).Append(*next)
+				groups = groups[:len(groups)-1] // Truncate off equal group
+				continue
+			}
+		}
+		groups = append(groups, ds)
+	}
+	return groups
+}
+
+// cleanupSurroundingIdentical scans through all unequal groups, and
+// moves any leading sequence of equal elements to the preceding equal group and
+// moves and trailing sequence of equal elements to the succeeding equal group.
+//
+// This is necessary since coalesceInterveningIdentical may coalesce edit groups
+// together such that leading/trailing spans of equal elements becomes possible.
+// Note that this can occur even with an optimal diffing algorithm.
+//
+// Example:
+//
+//	Input: [
+//		{NumIdentical: 61},
+//		{NumIdentical: 1 , NumRemoved: 11, NumInserted: 2}, // assume 3 leading identical elements
+//		{NumIdentical: 67},
+//		{NumIdentical: 7, NumRemoved: 12, NumInserted: 3},  // assume 10 trailing identical elements
+//		{NumIdentical: 54},
+//	]
+//	Output: [
+//		{NumIdentical: 64}, // incremented by 3
+//		{NumRemoved: 9},
+//		{NumIdentical: 67},
+//		{NumRemoved: 9},
+//		{NumIdentical: 64}, // incremented by 10
+//	]
+//
+func cleanupSurroundingIdentical(groups []diffStats, eq func(i, j int) bool) []diffStats {
+	var ix, iy int // indexes into sequence x and y
+	for i, ds := range groups {
+		// Handle equal group.
+		if ds.NumDiff() == 0 {
+			ix += ds.NumIdentical
+			iy += ds.NumIdentical
+			continue
+		}
+
+		// Handle unequal group.
+		nx := ds.NumIdentical + ds.NumRemoved + ds.NumModified
+		ny := ds.NumIdentical + ds.NumInserted + ds.NumModified
+		var numLeadingIdentical, numTrailingIdentical int
+		for i := 0; i < nx && i < ny && eq(ix+i, iy+i); i++ {
+			numLeadingIdentical++
+		}
+		for i := 0; i < nx && i < ny && eq(ix+nx-1-i, iy+ny-1-i); i++ {
+			numTrailingIdentical++
+		}
+		if numIdentical := numLeadingIdentical + numTrailingIdentical; numIdentical > 0 {
+			if numLeadingIdentical > 0 {
+				// Remove leading identical span from this group and
+				// insert it into the preceding group.
+				if i-1 >= 0 {
+					groups[i-1].NumIdentical += numLeadingIdentical
+				} else {
+					// No preceding group exists, so prepend a new group,
+					// but do so after we finish iterating over all groups.
+					defer func() {
+						groups = append([]diffStats{{Name: groups[0].Name, NumIdentical: numLeadingIdentical}}, groups...)
+					}()
+				}
+				// Increment indexes since the preceding group would have handled this.
+				ix += numLeadingIdentical
+				iy += numLeadingIdentical
+			}
+			if numTrailingIdentical > 0 {
+				// Remove trailing identical span from this group and
+				// insert it into the succeeding group.
+				if i+1 < len(groups) {
+					groups[i+1].NumIdentical += numTrailingIdentical
+				} else {
+					// No succeeding group exists, so append a new group,
+					// but do so after we finish iterating over all groups.
+					defer func() {
+						groups = append(groups, diffStats{Name: groups[len(groups)-1].Name, NumIdentical: numTrailingIdentical})
+					}()
+				}
+				// Do not increment indexes since the succeeding group will handle this.
+			}
+
+			// Update this group since some identical elements were removed.
+			nx -= numIdentical
+			ny -= numIdentical
+			groups[i] = diffStats{Name: ds.Name, NumRemoved: nx, NumInserted: ny}
+		}
+		ix += nx
+		iy += ny
+	}
+	return groups
+}

vendor/github.com/google/go-cmp/cmp/report_text.go

@@ -0,0 +1,431 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"bytes"
+	"fmt"
+	"math/rand"
+	"strings"
+	"time"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp/internal/flags"
+)
+
+var randBool = rand.New(rand.NewSource(time.Now().Unix())).Intn(2) == 0
+
+const maxColumnLength = 80
+
+type indentMode int
+
+func (n indentMode) appendIndent(b []byte, d diffMode) []byte {
+	// The output of Diff is documented as being unstable to provide future
+	// flexibility in changing the output for more humanly readable reports.
+	// This logic intentionally introduces instability to the exact output
+	// so that users can detect accidental reliance on stability early on,
+	// rather than much later when an actual change to the format occurs.
+	if flags.Deterministic || randBool {
+		// Use regular spaces (U+0020).
+		switch d {
+		case diffUnknown, diffIdentical:
+			b = append(b, "  "...)
+		case diffRemoved:
+			b = append(b, "- "...)
+		case diffInserted:
+			b = append(b, "+ "...)
+		}
+	} else {
+		// Use non-breaking spaces (U+00a0).
+		switch d {
+		case diffUnknown, diffIdentical:
+			b = append(b, "  "...)
+		case diffRemoved:
+			b = append(b, "- "...)
+		case diffInserted:
+			b = append(b, "+ "...)
+		}
+	}
+	return repeatCount(n).appendChar(b, '\t')
+}
+
+type repeatCount int
+
+func (n repeatCount) appendChar(b []byte, c byte) []byte {
+	for ; n > 0; n-- {
+		b = append(b, c)
+	}
+	return b
+}
+
+// textNode is a simplified tree-based representation of structured text.
+// Possible node types are textWrap, textList, or textLine.
+type textNode interface {
+	// Len reports the length in bytes of a single-line version of the tree.
+	// Nested textRecord.Diff and textRecord.Comment fields are ignored.
+	Len() int
+	// Equal reports whether the two trees are structurally identical.
+	// Nested textRecord.Diff and textRecord.Comment fields are compared.
+	Equal(textNode) bool
+	// String returns the string representation of the text tree.
+	// It is not guaranteed that len(x.String()) == x.Len(),
+	// nor that x.String() == y.String() implies that x.Equal(y).
+	String() string
+
+	// formatCompactTo formats the contents of the tree as a single-line string
+	// to the provided buffer. Any nested textRecord.Diff and textRecord.Comment
+	// fields are ignored.
+	//
+	// However, not all nodes in the tree should be collapsed as a single-line.
+	// If a node can be collapsed as a single-line, it is replaced by a textLine
+	// node. Since the top-level node cannot replace itself, this also returns
+	// the current node itself.
+	//
+	// This does not mutate the receiver.
+	formatCompactTo([]byte, diffMode) ([]byte, textNode)
+	// formatExpandedTo formats the contents of the tree as a multi-line string
+	// to the provided buffer. In order for column alignment to operate well,
+	// formatCompactTo must be called before calling formatExpandedTo.
+	formatExpandedTo([]byte, diffMode, indentMode) []byte
+}
+
+// textWrap is a wrapper that concatenates a prefix and/or a suffix
+// to the underlying node.
+type textWrap struct {
+	Prefix   string      // e.g., "bytes.Buffer{"
+	Value    textNode    // textWrap | textList | textLine
+	Suffix   string      // e.g., "}"
+	Metadata interface{} // arbitrary metadata; has no effect on formatting
+}
+
+func (s *textWrap) Len() int {
+	return len(s.Prefix) + s.Value.Len() + len(s.Suffix)
+}
+func (s1 *textWrap) Equal(s2 textNode) bool {
+	if s2, ok := s2.(*textWrap); ok {
+		return s1.Prefix == s2.Prefix && s1.Value.Equal(s2.Value) && s1.Suffix == s2.Suffix
+	}
+	return false
+}
+func (s *textWrap) String() string {
+	var d diffMode
+	var n indentMode
+	_, s2 := s.formatCompactTo(nil, d)
+	b := n.appendIndent(nil, d)      // Leading indent
+	b = s2.formatExpandedTo(b, d, n) // Main body
+	b = append(b, '\n')              // Trailing newline
+	return string(b)
+}
+func (s *textWrap) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) {
+	n0 := len(b) // Original buffer length
+	b = append(b, s.Prefix...)
+	b, s.Value = s.Value.formatCompactTo(b, d)
+	b = append(b, s.Suffix...)
+	if _, ok := s.Value.(textLine); ok {
+		return b, textLine(b[n0:])
+	}
+	return b, s
+}
+func (s *textWrap) formatExpandedTo(b []byte, d diffMode, n indentMode) []byte {
+	b = append(b, s.Prefix...)
+	b = s.Value.formatExpandedTo(b, d, n)
+	b = append(b, s.Suffix...)
+	return b
+}
+
+// textList is a comma-separated list of textWrap or textLine nodes.
+// The list may be formatted as multi-lines or single-line at the discretion
+// of the textList.formatCompactTo method.
+type textList []textRecord
+type textRecord struct {
+	Diff       diffMode     // e.g., 0 or '-' or '+'
+	Key        string       // e.g., "MyField"
+	Value      textNode     // textWrap | textLine
+	ElideComma bool         // avoid trailing comma
+	Comment    fmt.Stringer // e.g., "6 identical fields"
+}
+
+// AppendEllipsis appends a new ellipsis node to the list if none already
+// exists at the end. If cs is non-zero it coalesces the statistics with the
+// previous diffStats.
+func (s *textList) AppendEllipsis(ds diffStats) {
+	hasStats := !ds.IsZero()
+	if len(*s) == 0 || !(*s)[len(*s)-1].Value.Equal(textEllipsis) {
+		if hasStats {
+			*s = append(*s, textRecord{Value: textEllipsis, ElideComma: true, Comment: ds})
+		} else {
+			*s = append(*s, textRecord{Value: textEllipsis, ElideComma: true})
+		}
+		return
+	}
+	if hasStats {
+		(*s)[len(*s)-1].Comment = (*s)[len(*s)-1].Comment.(diffStats).Append(ds)
+	}
+}
+
+func (s textList) Len() (n int) {
+	for i, r := range s {
+		n += len(r.Key)
+		if r.Key != "" {
+			n += len(": ")
+		}
+		n += r.Value.Len()
+		if i < len(s)-1 {
+			n += len(", ")
+		}
+	}
+	return n
+}
+
+func (s1 textList) Equal(s2 textNode) bool {
+	if s2, ok := s2.(textList); ok {
+		if len(s1) != len(s2) {
+			return false
+		}
+		for i := range s1 {
+			r1, r2 := s1[i], s2[i]
+			if !(r1.Diff == r2.Diff && r1.Key == r2.Key && r1.Value.Equal(r2.Value) && r1.Comment == r2.Comment) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}
+
+func (s textList) String() string {
+	return (&textWrap{Prefix: "{", Value: s, Suffix: "}"}).String()
+}
+
+func (s textList) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) {
+	s = append(textList(nil), s...) // Avoid mutating original
+
+	// Determine whether we can collapse this list as a single line.
+	n0 := len(b) // Original buffer length
+	var multiLine bool
+	for i, r := range s {
+		if r.Diff == diffInserted || r.Diff == diffRemoved {
+			multiLine = true
+		}
+		b = append(b, r.Key...)
+		if r.Key != "" {
+			b = append(b, ": "...)
+		}
+		b, s[i].Value = r.Value.formatCompactTo(b, d|r.Diff)
+		if _, ok := s[i].Value.(textLine); !ok {
+			multiLine = true
+		}
+		if r.Comment != nil {
+			multiLine = true
+		}
+		if i < len(s)-1 {
+			b = append(b, ", "...)
+		}
+	}
+	// Force multi-lined output when printing a removed/inserted node that
+	// is sufficiently long.
+	if (d == diffInserted || d == diffRemoved) && len(b[n0:]) > maxColumnLength {
+		multiLine = true
+	}
+	if !multiLine {
+		return b, textLine(b[n0:])
+	}
+	return b, s
+}
+
+func (s textList) formatExpandedTo(b []byte, d diffMode, n indentMode) []byte {
+	alignKeyLens := s.alignLens(
+		func(r textRecord) bool {
+			_, isLine := r.Value.(textLine)
+			return r.Key == "" || !isLine
+		},
+		func(r textRecord) int { return utf8.RuneCountInString(r.Key) },
+	)
+	alignValueLens := s.alignLens(
+		func(r textRecord) bool {
+			_, isLine := r.Value.(textLine)
+			return !isLine || r.Value.Equal(textEllipsis) || r.Comment == nil
+		},
+		func(r textRecord) int { return utf8.RuneCount(r.Value.(textLine)) },
+	)
+
+	// Format lists of simple lists in a batched form.
+	// If the list is sequence of only textLine values,
+	// then batch multiple values on a single line.
+	var isSimple bool
+	for _, r := range s {
+		_, isLine := r.Value.(textLine)
+		isSimple = r.Diff == 0 && r.Key == "" && isLine && r.Comment == nil
+		if !isSimple {
+			break
+		}
+	}
+	if isSimple {
+		n++
+		var batch []byte
+		emitBatch := func() {
+			if len(batch) > 0 {
+				b = n.appendIndent(append(b, '\n'), d)
+				b = append(b, bytes.TrimRight(batch, " ")...)
+				batch = batch[:0]
+			}
+		}
+		for _, r := range s {
+			line := r.Value.(textLine)
+			if len(batch)+len(line)+len(", ") > maxColumnLength {
+				emitBatch()
+			}
+			batch = append(batch, line...)
+			batch = append(batch, ", "...)
+		}
+		emitBatch()
+		n--
+		return n.appendIndent(append(b, '\n'), d)
+	}
+
+	// Format the list as a multi-lined output.
+	n++
+	for i, r := range s {
+		b = n.appendIndent(append(b, '\n'), d|r.Diff)
+		if r.Key != "" {
+			b = append(b, r.Key+": "...)
+		}
+		b = alignKeyLens[i].appendChar(b, ' ')
+
+		b = r.Value.formatExpandedTo(b, d|r.Diff, n)
+		if !r.ElideComma {
+			b = append(b, ',')
+		}
+		b = alignValueLens[i].appendChar(b, ' ')
+
+		if r.Comment != nil {
+			b = append(b, " // "+r.Comment.String()...)
+		}
+	}
+	n--
+
+	return n.appendIndent(append(b, '\n'), d)
+}
+
+func (s textList) alignLens(
+	skipFunc func(textRecord) bool,
+	lenFunc func(textRecord) int,
+) []repeatCount {
+	var startIdx, endIdx, maxLen int
+	lens := make([]repeatCount, len(s))
+	for i, r := range s {
+		if skipFunc(r) {
+			for j := startIdx; j < endIdx && j < len(s); j++ {
+				lens[j] = repeatCount(maxLen - lenFunc(s[j]))
+			}
+			startIdx, endIdx, maxLen = i+1, i+1, 0
+		} else {
+			if maxLen < lenFunc(r) {
+				maxLen = lenFunc(r)
+			}
+			endIdx = i + 1
+		}
+	}
+	for j := startIdx; j < endIdx && j < len(s); j++ {
+		lens[j] = repeatCount(maxLen - lenFunc(s[j]))
+	}
+	return lens
+}
+
+// textLine is a single-line segment of text and is always a leaf node
+// in the textNode tree.
+type textLine []byte
+
+var (
+	textNil      = textLine("nil")
+	textEllipsis = textLine("...")
+)
+
+func (s textLine) Len() int {
+	return len(s)
+}
+func (s1 textLine) Equal(s2 textNode) bool {
+	if s2, ok := s2.(textLine); ok {
+		return bytes.Equal([]byte(s1), []byte(s2))
+	}
+	return false
+}
+func (s textLine) String() string {
+	return string(s)
+}
+func (s textLine) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) {
+	return append(b, s...), s
+}
+func (s textLine) formatExpandedTo(b []byte, _ diffMode, _ indentMode) []byte {
+	return append(b, s...)
+}
+
+type diffStats struct {
+	Name         string
+	NumIgnored   int
+	NumIdentical int
+	NumRemoved   int
+	NumInserted  int
+	NumModified  int
+}
+
+func (s diffStats) IsZero() bool {
+	s.Name = ""
+	return s == diffStats{}
+}
+
+func (s diffStats) NumDiff() int {
+	return s.NumRemoved + s.NumInserted + s.NumModified
+}
+
+func (s diffStats) Append(ds diffStats) diffStats {
+	assert(s.Name == ds.Name)
+	s.NumIgnored += ds.NumIgnored
+	s.NumIdentical += ds.NumIdentical
+	s.NumRemoved += ds.NumRemoved
+	s.NumInserted += ds.NumInserted
+	s.NumModified += ds.NumModified
+	return s
+}
+
+// String prints a humanly-readable summary of coalesced records.
+//
+// Example:
+//	diffStats{Name: "Field", NumIgnored: 5}.String() => "5 ignored fields"
+func (s diffStats) String() string {
+	var ss []string
+	var sum int
+	labels := [...]string{"ignored", "identical", "removed", "inserted", "modified"}
+	counts := [...]int{s.NumIgnored, s.NumIdentical, s.NumRemoved, s.NumInserted, s.NumModified}
+	for i, n := range counts {
+		if n > 0 {
+			ss = append(ss, fmt.Sprintf("%d %v", n, labels[i]))
+		}
+		sum += n
+	}
+
+	// Pluralize the name (adjusting for some obscure English grammar rules).
+	name := s.Name
+	if sum > 1 {
+		name += "s"
+		if strings.HasSuffix(name, "ys") {
+			name = name[:len(name)-2] + "ies" // e.g., "entrys" => "entries"
+		}
+	}
+
+	// Format the list according to English grammar (with Oxford comma).
+	switch n := len(ss); n {
+	case 0:
+		return ""
+	case 1, 2:
+		return strings.Join(ss, " and ") + " " + name
+	default:
+		return strings.Join(ss[:n-1], ", ") + ", and " + ss[n-1] + " " + name
+	}
+}
+
+type commentString string
+
+func (s commentString) String() string { return string(s) }

vendor/github.com/google/go-cmp/cmp/report_value.go

@@ -0,0 +1,121 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import "reflect"
+
+// valueNode represents a single node within a report, which is a
+// structured representation of the value tree, containing information
+// regarding which nodes are equal or not.
+type valueNode struct {
+	parent *valueNode
+
+	Type   reflect.Type
+	ValueX reflect.Value
+	ValueY reflect.Value
+
+	// NumSame is the number of leaf nodes that are equal.
+	// All descendants are equal only if NumDiff is 0.
+	NumSame int
+	// NumDiff is the number of leaf nodes that are not equal.
+	NumDiff int
+	// NumIgnored is the number of leaf nodes that are ignored.
+	NumIgnored int
+	// NumCompared is the number of leaf nodes that were compared
+	// using an Equal method or Comparer function.
+	NumCompared int
+	// NumTransformed is the number of non-leaf nodes that were transformed.
+	NumTransformed int
+	// NumChildren is the number of transitive descendants of this node.
+	// This counts from zero; thus, leaf nodes have no descendants.
+	NumChildren int
+	// MaxDepth is the maximum depth of the tree. This counts from zero;
+	// thus, leaf nodes have a depth of zero.
+	MaxDepth int
+
+	// Records is a list of struct fields, slice elements, or map entries.
+	Records []reportRecord // If populated, implies Value is not populated
+
+	// Value is the result of a transformation, pointer indirect, of
+	// type assertion.
+	Value *valueNode // If populated, implies Records is not populated
+
+	// TransformerName is the name of the transformer.
+	TransformerName string // If non-empty, implies Value is populated
+}
+type reportRecord struct {
+	Key   reflect.Value // Invalid for slice element
+	Value *valueNode
+}
+
+func (parent *valueNode) PushStep(ps PathStep) (child *valueNode) {
+	vx, vy := ps.Values()
+	child = &valueNode{parent: parent, Type: ps.Type(), ValueX: vx, ValueY: vy}
+	switch s := ps.(type) {
+	case StructField:
+		assert(parent.Value == nil)
+		parent.Records = append(parent.Records, reportRecord{Key: reflect.ValueOf(s.Name()), Value: child})
+	case SliceIndex:
+		assert(parent.Value == nil)
+		parent.Records = append(parent.Records, reportRecord{Value: child})
+	case MapIndex:
+		assert(parent.Value == nil)
+		parent.Records = append(parent.Records, reportRecord{Key: s.Key(), Value: child})
+	case Indirect:
+		assert(parent.Value == nil && parent.Records == nil)
+		parent.Value = child
+	case TypeAssertion:
+		assert(parent.Value == nil && parent.Records == nil)
+		parent.Value = child
+	case Transform:
+		assert(parent.Value == nil && parent.Records == nil)
+		parent.Value = child
+		parent.TransformerName = s.Name()
+		parent.NumTransformed++
+	default:
+		assert(parent == nil) // Must be the root step
+	}
+	return child
+}
+
+func (r *valueNode) Report(rs Result) {
+	assert(r.MaxDepth == 0) // May only be called on leaf nodes
+
+	if rs.ByIgnore() {
+		r.NumIgnored++
+	} else {
+		if rs.Equal() {
+			r.NumSame++
+		} else {
+			r.NumDiff++
+		}
+	}
+	assert(r.NumSame+r.NumDiff+r.NumIgnored == 1)
+
+	if rs.ByMethod() {
+		r.NumCompared++
+	}
+	if rs.ByFunc() {
+		r.NumCompared++
+	}
+	assert(r.NumCompared <= 1)
+}
+
+func (child *valueNode) PopStep() (parent *valueNode) {
+	if child.parent == nil {
+		return nil
+	}
+	parent = child.parent
+	parent.NumSame += child.NumSame
+	parent.NumDiff += child.NumDiff
+	parent.NumIgnored += child.NumIgnored
+	parent.NumCompared += child.NumCompared
+	parent.NumTransformed += child.NumTransformed
+	parent.NumChildren += child.NumChildren + 1
+	if parent.MaxDepth < child.MaxDepth+1 {
+		parent.MaxDepth = child.MaxDepth + 1
+	}
+	return parent
+}

vendor/go.opencensus.io/plugin/ocgrpc/client.go

@@ -0,0 +1,56 @@
+// Copyright 2018, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ocgrpc
+
+import (
+	"context"
+
+	"go.opencensus.io/trace"
+	"google.golang.org/grpc/stats"
+)
+
+// ClientHandler implements a gRPC stats.Handler for recording OpenCensus stats and
+// traces. Use with gRPC clients only.
+type ClientHandler struct {
+	// StartOptions allows configuring the StartOptions used to create new spans.
+	//
+	// StartOptions.SpanKind will always be set to trace.SpanKindClient
+	// for spans started by this handler.
+	StartOptions trace.StartOptions
+}
+
+// HandleConn exists to satisfy gRPC stats.Handler.
+func (c *ClientHandler) HandleConn(ctx context.Context, cs stats.ConnStats) {
+	// no-op
+}
+
+// TagConn exists to satisfy gRPC stats.Handler.
+func (c *ClientHandler) TagConn(ctx context.Context, cti *stats.ConnTagInfo) context.Context {
+	// no-op
+	return ctx
+}
+
+// HandleRPC implements per-RPC tracing and stats instrumentation.
+func (c *ClientHandler) HandleRPC(ctx context.Context, rs stats.RPCStats) {
+	traceHandleRPC(ctx, rs)
+	statsHandleRPC(ctx, rs)
+}
+
+// TagRPC implements per-RPC context management.
+func (c *ClientHandler) TagRPC(ctx context.Context, rti *stats.RPCTagInfo) context.Context {
+	ctx = c.traceTagRPC(ctx, rti)
+	ctx = c.statsTagRPC(ctx, rti)
+	return ctx
+}

vendor/go.opencensus.io/plugin/ocgrpc/client_metrics.go

@@ -0,0 +1,109 @@
+// Copyright 2017, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package ocgrpc
+
+import (
+	"go.opencensus.io/stats"
+	"go.opencensus.io/stats/view"
+	"go.opencensus.io/tag"
+)
+
+// The following variables are measures are recorded by ClientHandler:
+var (
+	ClientSentMessagesPerRPC     = stats.Int64("grpc.io/client/sent_messages_per_rpc", "Number of messages sent in the RPC (always 1 for non-streaming RPCs).", stats.UnitDimensionless)
+	ClientSentBytesPerRPC        = stats.Int64("grpc.io/client/sent_bytes_per_rpc", "Total bytes sent across all request messages per RPC.", stats.UnitBytes)
+	ClientReceivedMessagesPerRPC = stats.Int64("grpc.io/client/received_messages_per_rpc", "Number of response messages received per RPC (always 1 for non-streaming RPCs).", stats.UnitDimensionless)
+	ClientReceivedBytesPerRPC    = stats.Int64("grpc.io/client/received_bytes_per_rpc", "Total bytes received across all response messages per RPC.", stats.UnitBytes)
+	ClientRoundtripLatency       = stats.Float64("grpc.io/client/roundtrip_latency", "Time between first byte of request sent to last byte of response received, or terminal error.", stats.UnitMilliseconds)
+	ClientServerLatency          = stats.Float64("grpc.io/client/server_latency", `Propagated from the server and should have the same value as "grpc.io/server/latency".`, stats.UnitMilliseconds)
+)
+
+// Predefined views may be registered to collect data for the above measures.
+// As always, you may also define your own custom views over measures collected by this
+// package. These are declared as a convenience only; none are registered by
+// default.
+var (
+	ClientSentBytesPerRPCView = &view.View{
+		Measure:     ClientSentBytesPerRPC,
+		Name:        "grpc.io/client/sent_bytes_per_rpc",
+		Description: "Distribution of bytes sent per RPC, by method.",
+		TagKeys:     []tag.Key{KeyClientMethod},
+		Aggregation: DefaultBytesDistribution,
+	}
+
+	ClientReceivedBytesPerRPCView = &view.View{
+		Measure:     ClientReceivedBytesPerRPC,
+		Name:        "grpc.io/client/received_bytes_per_rpc",
+		Description: "Distribution of bytes received per RPC, by method.",
+		TagKeys:     []tag.Key{KeyClientMethod},
+		Aggregation: DefaultBytesDistribution,
+	}
+
+	ClientRoundtripLatencyView = &view.View{
+		Measure:     ClientRoundtripLatency,
+		Name:        "grpc.io/client/roundtrip_latency",
+		Description: "Distribution of round-trip latency, by method.",
+		TagKeys:     []tag.Key{KeyClientMethod},
+		Aggregation: DefaultMillisecondsDistribution,
+	}
+
+	// Purposely reuses the count from `ClientRoundtripLatency`, tagging
+	// with method and status to result in ClientCompletedRpcs.
+	ClientCompletedRPCsView = &view.View{
+		Measure:     ClientRoundtripLatency,
+		Name:        "grpc.io/client/completed_rpcs",
+		Description: "Count of RPCs by method and status.",
+		TagKeys:     []tag.Key{KeyClientMethod, KeyClientStatus},
+		Aggregation: view.Count(),
+	}
+
+	ClientSentMessagesPerRPCView = &view.View{
+		Measure:     ClientSentMessagesPerRPC,
+		Name:        "grpc.io/client/sent_messages_per_rpc",
+		Description: "Distribution of sent messages count per RPC, by method.",
+		TagKeys:     []tag.Key{KeyClientMethod},
+		Aggregation: DefaultMessageCountDistribution,
+	}
+
+	ClientReceivedMessagesPerRPCView = &view.View{
+		Measure:     ClientReceivedMessagesPerRPC,
+		Name:        "grpc.io/client/received_messages_per_rpc",
+		Description: "Distribution of received messages count per RPC, by method.",
+		TagKeys:     []tag.Key{KeyClientMethod},
+		Aggregation: DefaultMessageCountDistribution,
+	}
+
+	ClientServerLatencyView = &view.View{
+		Measure:     ClientServerLatency,
+		Name:        "grpc.io/client/server_latency",
+		Description: "Distribution of server latency as viewed by client, by method.",
+		TagKeys:     []tag.Key{KeyClientMethod},
+		Aggregation: DefaultMillisecondsDistribution,
+	}
+)
+
+// DefaultClientViews are the default client views provided by this package.
+var DefaultClientViews = []*view.View{
+	ClientSentBytesPerRPCView,
+	ClientReceivedBytesPerRPCView,
+	ClientRoundtripLatencyView,
+	ClientCompletedRPCsView,
+}
+
+// TODO(jbd): Add roundtrip_latency, uncompressed_request_bytes, uncompressed_response_bytes, request_count, response_count.
+// TODO(acetechnologist): This is temporary and will need to be replaced by a
+// mechanism to load these defaults from a common repository/config shared by
+// all supported languages. Likely a serialized protobuf of these defaults.

vendor/go.opencensus.io/plugin/ocgrpc/client_stats_handler.go

@@ -0,0 +1,49 @@
+// Copyright 2017, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package ocgrpc
+
+import (
+	"context"
+	"time"
+
+	"go.opencensus.io/tag"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/stats"
+)
+
+// statsTagRPC gets the tag.Map populated by the application code, serializes
+// its tags into the GRPC metadata in order to be sent to the server.
+func (h *ClientHandler) statsTagRPC(ctx context.Context, info *stats.RPCTagInfo) context.Context {
+	startTime := time.Now()
+	if info == nil {
+		if grpclog.V(2) {
+			grpclog.Info("clientHandler.TagRPC called with nil info.")
+		}
+		return ctx
+	}
+
+	d := &rpcData{
+		startTime: startTime,
+		method:    info.FullMethodName,
+	}
+	ts := tag.FromContext(ctx)
+	if ts != nil {
+		encoded := tag.Encode(ts)
+		ctx = stats.SetTags(ctx, encoded)
+	}
+
+	return context.WithValue(ctx, rpcDataKey, d)
+}

vendor/go.opencensus.io/plugin/ocgrpc/doc.go

@@ -0,0 +1,19 @@
+// Copyright 2017, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package ocgrpc contains OpenCensus stats and trace
+// integrations for gRPC.
+//
+// Use ServerHandler for servers and ClientHandler for clients.
+package ocgrpc // import "go.opencensus.io/plugin/ocgrpc"

vendor/go.opencensus.io/plugin/ocgrpc/server.go

@@ -0,0 +1,81 @@
+// Copyright 2018, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ocgrpc
+
+import (
+	"context"
+
+	"google.golang.org/grpc/stats"
+
+	"go.opencensus.io/trace"
+)
+
+// ServerHandler implements gRPC stats.Handler recording OpenCensus stats and
+// traces. Use with gRPC servers.
+//
+// When installed (see Example), tracing metadata is read from inbound RPCs
+// by default. If no tracing metadata is present, or if the tracing metadata is
+// present but the SpanContext isn't sampled, then a new trace may be started
+// (as determined by Sampler).
+type ServerHandler struct {
+	// IsPublicEndpoint may be set to true to always start a new trace around
+	// each RPC. Any SpanContext in the RPC metadata will be added as a linked
+	// span instead of making it the parent of the span created around the
+	// server RPC.
+	//
+	// Be aware that if you leave this false (the default) on a public-facing
+	// server, callers will be able to send tracing metadata in gRPC headers
+	// and trigger traces in your backend.
+	IsPublicEndpoint bool
+
+	// StartOptions to use for to spans started around RPCs handled by this server.
+	//
+	// These will apply even if there is tracing metadata already
+	// present on the inbound RPC but the SpanContext is not sampled. This
+	// ensures that each service has some opportunity to be traced. If you would
+	// like to not add any additional traces for this gRPC service, set:
+	//
+	//   StartOptions.Sampler = trace.ProbabilitySampler(0.0)
+	//
+	// StartOptions.SpanKind will always be set to trace.SpanKindServer
+	// for spans started by this handler.
+	StartOptions trace.StartOptions
+}
+
+var _ stats.Handler = (*ServerHandler)(nil)
+
+// HandleConn exists to satisfy gRPC stats.Handler.
+func (s *ServerHandler) HandleConn(ctx context.Context, cs stats.ConnStats) {
+	// no-op
+}
+
+// TagConn exists to satisfy gRPC stats.Handler.
+func (s *ServerHandler) TagConn(ctx context.Context, cti *stats.ConnTagInfo) context.Context {
+	// no-op
+	return ctx
+}
+
+// HandleRPC implements per-RPC tracing and stats instrumentation.
+func (s *ServerHandler) HandleRPC(ctx context.Context, rs stats.RPCStats) {
+	traceHandleRPC(ctx, rs)
+	statsHandleRPC(ctx, rs)
+}
+
+// TagRPC implements per-RPC context management.
+func (s *ServerHandler) TagRPC(ctx context.Context, rti *stats.RPCTagInfo) context.Context {
+	ctx = s.traceTagRPC(ctx, rti)
+	ctx = s.statsTagRPC(ctx, rti)
+	return ctx
+}

vendor/go.opencensus.io/plugin/ocgrpc/server_metrics.go

@@ -0,0 +1,99 @@
+// Copyright 2017, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package ocgrpc
+
+import (
+	"go.opencensus.io/stats"
+	"go.opencensus.io/stats/view"
+	"go.opencensus.io/tag"
+)
+
+// The following variables are measures are recorded by ServerHandler:
+var (
+	ServerReceivedMessagesPerRPC = stats.Int64("grpc.io/server/received_messages_per_rpc", "Number of messages received in each RPC. Has value 1 for non-streaming RPCs.", stats.UnitDimensionless)
+	ServerReceivedBytesPerRPC    = stats.Int64("grpc.io/server/received_bytes_per_rpc", "Total bytes received across all messages per RPC.", stats.UnitBytes)
+	ServerSentMessagesPerRPC     = stats.Int64("grpc.io/server/sent_messages_per_rpc", "Number of messages sent in each RPC. Has value 1 for non-streaming RPCs.", stats.UnitDimensionless)
+	ServerSentBytesPerRPC        = stats.Int64("grpc.io/server/sent_bytes_per_rpc", "Total bytes sent in across all response messages per RPC.", stats.UnitBytes)
+	ServerLatency                = stats.Float64("grpc.io/server/server_latency", "Time between first byte of request received to last byte of response sent, or terminal error.", stats.UnitMilliseconds)
+)
+
+// TODO(acetechnologist): This is temporary and will need to be replaced by a
+// mechanism to load these defaults from a common repository/config shared by
+// all supported languages. Likely a serialized protobuf of these defaults.
+
+// Predefined views may be registered to collect data for the above measures.
+// As always, you may also define your own custom views over measures collected by this
+// package. These are declared as a convenience only; none are registered by
+// default.
+var (
+	ServerReceivedBytesPerRPCView = &view.View{
+		Name:        "grpc.io/server/received_bytes_per_rpc",
+		Description: "Distribution of received bytes per RPC, by method.",
+		Measure:     ServerReceivedBytesPerRPC,
+		TagKeys:     []tag.Key{KeyServerMethod},
+		Aggregation: DefaultBytesDistribution,
+	}
+
+	ServerSentBytesPerRPCView = &view.View{
+		Name:        "grpc.io/server/sent_bytes_per_rpc",
+		Description: "Distribution of total sent bytes per RPC, by method.",
+		Measure:     ServerSentBytesPerRPC,
+		TagKeys:     []tag.Key{KeyServerMethod},
+		Aggregation: DefaultBytesDistribution,
+	}
+
+	ServerLatencyView = &view.View{
+		Name:        "grpc.io/server/server_latency",
+		Description: "Distribution of server latency in milliseconds, by method.",
+		TagKeys:     []tag.Key{KeyServerMethod},
+		Measure:     ServerLatency,
+		Aggregation: DefaultMillisecondsDistribution,
+	}
+
+	// Purposely reuses the count from `ServerLatency`, tagging
+	// with method and status to result in ServerCompletedRpcs.
+	ServerCompletedRPCsView = &view.View{
+		Name:        "grpc.io/server/completed_rpcs",
+		Description: "Count of RPCs by method and status.",
+		TagKeys:     []tag.Key{KeyServerMethod, KeyServerStatus},
+		Measure:     ServerLatency,
+		Aggregation: view.Count(),
+	}
+
+	ServerReceivedMessagesPerRPCView = &view.View{
+		Name:        "grpc.io/server/received_messages_per_rpc",
+		Description: "Distribution of messages received count per RPC, by method.",
+		TagKeys:     []tag.Key{KeyServerMethod},
+		Measure:     ServerReceivedMessagesPerRPC,
+		Aggregation: DefaultMessageCountDistribution,
+	}
+
+	ServerSentMessagesPerRPCView = &view.View{
+		Name:        "grpc.io/server/sent_messages_per_rpc",
+		Description: "Distribution of messages sent count per RPC, by method.",
+		TagKeys:     []tag.Key{KeyServerMethod},
+		Measure:     ServerSentMessagesPerRPC,
+		Aggregation: DefaultMessageCountDistribution,
+	}
+)
+
+// DefaultServerViews are the default server views provided by this package.
+var DefaultServerViews = []*view.View{
+	ServerReceivedBytesPerRPCView,
+	ServerSentBytesPerRPCView,
+	ServerLatencyView,
+	ServerCompletedRPCsView,
+}

vendor/go.opencensus.io/plugin/ocgrpc/server_stats_handler.go

@@ -0,0 +1,63 @@
+// Copyright 2017, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package ocgrpc
+
+import (
+	"time"
+
+	"context"
+
+	"go.opencensus.io/tag"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/stats"
+)
+
+// statsTagRPC gets the metadata from gRPC context, extracts the encoded tags from
+// it and creates a new tag.Map and puts them into the returned context.
+func (h *ServerHandler) statsTagRPC(ctx context.Context, info *stats.RPCTagInfo) context.Context {
+	startTime := time.Now()
+	if info == nil {
+		if grpclog.V(2) {
+			grpclog.Infof("opencensus: TagRPC called with nil info.")
+		}
+		return ctx
+	}
+	d := &rpcData{
+		startTime: startTime,
+		method:    info.FullMethodName,
+	}
+	propagated := h.extractPropagatedTags(ctx)
+	ctx = tag.NewContext(ctx, propagated)
+	ctx, _ = tag.New(ctx, tag.Upsert(KeyServerMethod, methodName(info.FullMethodName)))
+	return context.WithValue(ctx, rpcDataKey, d)
+}
+
+// extractPropagatedTags creates a new tag map containing the tags extracted from the
+// gRPC metadata.
+func (h *ServerHandler) extractPropagatedTags(ctx context.Context) *tag.Map {
+	buf := stats.Tags(ctx)
+	if buf == nil {
+		return nil
+	}
+	propagated, err := tag.Decode(buf)
+	if err != nil {
+		if grpclog.V(2) {
+			grpclog.Warningf("opencensus: Failed to decode tags from gRPC metadata failed to decode: %v", err)
+		}
+		return nil
+	}
+	return propagated
+}

vendor/go.opencensus.io/plugin/ocgrpc/stats_common.go

@@ -0,0 +1,227 @@
+// Copyright 2017, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package ocgrpc
+
+import (
+	"context"
+	"strconv"
+	"strings"
+	"sync/atomic"
+	"time"
+
+	"go.opencensus.io/metric/metricdata"
+	ocstats "go.opencensus.io/stats"
+	"go.opencensus.io/stats/view"
+	"go.opencensus.io/tag"
+	"go.opencensus.io/trace"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
+)
+
+type grpcInstrumentationKey string
+
+// rpcData holds the instrumentation RPC data that is needed between the start
+// and end of an call. It holds the info that this package needs to keep track
+// of between the various GRPC events.
+type rpcData struct {
+	// reqCount and respCount has to be the first words
+	// in order to be 64-aligned on 32-bit architectures.
+	sentCount, sentBytes, recvCount, recvBytes int64 // access atomically
+
+	// startTime represents the time at which TagRPC was invoked at the
+	// beginning of an RPC. It is an appoximation of the time when the
+	// application code invoked GRPC code.
+	startTime time.Time
+	method    string
+}
+
+// The following variables define the default hard-coded auxiliary data used by
+// both the default GRPC client and GRPC server metrics.
+var (
+	DefaultBytesDistribution        = view.Distribution(1024, 2048, 4096, 16384, 65536, 262144, 1048576, 4194304, 16777216, 67108864, 268435456, 1073741824, 4294967296)
+	DefaultMillisecondsDistribution = view.Distribution(0.01, 0.05, 0.1, 0.3, 0.6, 0.8, 1, 2, 3, 4, 5, 6, 8, 10, 13, 16, 20, 25, 30, 40, 50, 65, 80, 100, 130, 160, 200, 250, 300, 400, 500, 650, 800, 1000, 2000, 5000, 10000, 20000, 50000, 100000)
+	DefaultMessageCountDistribution = view.Distribution(1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536)
+)
+
+// Server tags are applied to the context used to process each RPC, as well as
+// the measures at the end of each RPC.
+var (
+	KeyServerMethod = tag.MustNewKey("grpc_server_method")
+	KeyServerStatus = tag.MustNewKey("grpc_server_status")
+)
+
+// Client tags are applied to measures at the end of each RPC.
+var (
+	KeyClientMethod = tag.MustNewKey("grpc_client_method")
+	KeyClientStatus = tag.MustNewKey("grpc_client_status")
+)
+
+var (
+	rpcDataKey = grpcInstrumentationKey("opencensus-rpcData")
+)
+
+func methodName(fullname string) string {
+	return strings.TrimLeft(fullname, "/")
+}
+
+// statsHandleRPC processes the RPC events.
+func statsHandleRPC(ctx context.Context, s stats.RPCStats) {
+	switch st := s.(type) {
+	case *stats.Begin, *stats.OutHeader, *stats.InHeader, *stats.InTrailer, *stats.OutTrailer:
+		// do nothing for client
+	case *stats.OutPayload:
+		handleRPCOutPayload(ctx, st)
+	case *stats.InPayload:
+		handleRPCInPayload(ctx, st)
+	case *stats.End:
+		handleRPCEnd(ctx, st)
+	default:
+		grpclog.Infof("unexpected stats: %T", st)
+	}
+}
+
+func handleRPCOutPayload(ctx context.Context, s *stats.OutPayload) {
+	d, ok := ctx.Value(rpcDataKey).(*rpcData)
+	if !ok {
+		if grpclog.V(2) {
+			grpclog.Infoln("Failed to retrieve *rpcData from context.")
+		}
+		return
+	}
+
+	atomic.AddInt64(&d.sentBytes, int64(s.Length))
+	atomic.AddInt64(&d.sentCount, 1)
+}
+
+func handleRPCInPayload(ctx context.Context, s *stats.InPayload) {
+	d, ok := ctx.Value(rpcDataKey).(*rpcData)
+	if !ok {
+		if grpclog.V(2) {
+			grpclog.Infoln("Failed to retrieve *rpcData from context.")
+		}
+		return
+	}
+
+	atomic.AddInt64(&d.recvBytes, int64(s.Length))
+	atomic.AddInt64(&d.recvCount, 1)
+}
+
+func handleRPCEnd(ctx context.Context, s *stats.End) {
+	d, ok := ctx.Value(rpcDataKey).(*rpcData)
+	if !ok {
+		if grpclog.V(2) {
+			grpclog.Infoln("Failed to retrieve *rpcData from context.")
+		}
+		return
+	}
+
+	elapsedTime := time.Since(d.startTime)
+
+	var st string
+	if s.Error != nil {
+		s, ok := status.FromError(s.Error)
+		if ok {
+			st = statusCodeToString(s)
+		}
+	} else {
+		st = "OK"
+	}
+
+	latencyMillis := float64(elapsedTime) / float64(time.Millisecond)
+	attachments := getSpanCtxAttachment(ctx)
+	if s.Client {
+		ocstats.RecordWithOptions(ctx,
+			ocstats.WithTags(
+				tag.Upsert(KeyClientMethod, methodName(d.method)),
+				tag.Upsert(KeyClientStatus, st)),
+			ocstats.WithAttachments(attachments),
+			ocstats.WithMeasurements(
+				ClientSentBytesPerRPC.M(atomic.LoadInt64(&d.sentBytes)),
+				ClientSentMessagesPerRPC.M(atomic.LoadInt64(&d.sentCount)),
+				ClientReceivedMessagesPerRPC.M(atomic.LoadInt64(&d.recvCount)),
+				ClientReceivedBytesPerRPC.M(atomic.LoadInt64(&d.recvBytes)),
+				ClientRoundtripLatency.M(latencyMillis)))
+	} else {
+		ocstats.RecordWithOptions(ctx,
+			ocstats.WithTags(
+				tag.Upsert(KeyServerStatus, st),
+			),
+			ocstats.WithAttachments(attachments),
+			ocstats.WithMeasurements(
+				ServerSentBytesPerRPC.M(atomic.LoadInt64(&d.sentBytes)),
+				ServerSentMessagesPerRPC.M(atomic.LoadInt64(&d.sentCount)),
+				ServerReceivedMessagesPerRPC.M(atomic.LoadInt64(&d.recvCount)),
+				ServerReceivedBytesPerRPC.M(atomic.LoadInt64(&d.recvBytes)),
+				ServerLatency.M(latencyMillis)))
+	}
+}
+
+func statusCodeToString(s *status.Status) string {
+	// see https://github.com/grpc/grpc/blob/master/doc/statuscodes.md
+	switch c := s.Code(); c {
+	case codes.OK:
+		return "OK"
+	case codes.Canceled:
+		return "CANCELLED"
+	case codes.Unknown:
+		return "UNKNOWN"
+	case codes.InvalidArgument:
+		return "INVALID_ARGUMENT"
+	case codes.DeadlineExceeded:
+		return "DEADLINE_EXCEEDED"
+	case codes.NotFound:
+		return "NOT_FOUND"
+	case codes.AlreadyExists:
+		return "ALREADY_EXISTS"
+	case codes.PermissionDenied:
+		return "PERMISSION_DENIED"
+	case codes.ResourceExhausted:
+		return "RESOURCE_EXHAUSTED"
+	case codes.FailedPrecondition:
+		return "FAILED_PRECONDITION"
+	case codes.Aborted:
+		return "ABORTED"
+	case codes.OutOfRange:
+		return "OUT_OF_RANGE"
+	case codes.Unimplemented:
+		return "UNIMPLEMENTED"
+	case codes.Internal:
+		return "INTERNAL"
+	case codes.Unavailable:
+		return "UNAVAILABLE"
+	case codes.DataLoss:
+		return "DATA_LOSS"
+	case codes.Unauthenticated:
+		return "UNAUTHENTICATED"
+	default:
+		return "CODE_" + strconv.FormatInt(int64(c), 10)
+	}
+}
+
+func getSpanCtxAttachment(ctx context.Context) metricdata.Attachments {
+	attachments := map[string]interface{}{}
+	span := trace.FromContext(ctx)
+	if span == nil {
+		return attachments
+	}
+	spanCtx := span.SpanContext()
+	if spanCtx.IsSampled() {
+		attachments[metricdata.AttachmentKeySpanContext] = spanCtx
+	}
+	return attachments
+}

vendor/go.opencensus.io/plugin/ocgrpc/trace_common.go

@@ -0,0 +1,107 @@
+// Copyright 2017, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ocgrpc
+
+import (
+	"context"
+	"strings"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
+
+	"go.opencensus.io/trace"
+	"go.opencensus.io/trace/propagation"
+)
+
+const traceContextKey = "grpc-trace-bin"
+
+// TagRPC creates a new trace span for the client side of the RPC.
+//
+// It returns ctx with the new trace span added and a serialization of the
+// SpanContext added to the outgoing gRPC metadata.
+func (c *ClientHandler) traceTagRPC(ctx context.Context, rti *stats.RPCTagInfo) context.Context {
+	name := strings.TrimPrefix(rti.FullMethodName, "/")
+	name = strings.Replace(name, "/", ".", -1)
+	ctx, span := trace.StartSpan(ctx, name,
+		trace.WithSampler(c.StartOptions.Sampler),
+		trace.WithSpanKind(trace.SpanKindClient)) // span is ended by traceHandleRPC
+	traceContextBinary := propagation.Binary(span.SpanContext())
+	return metadata.AppendToOutgoingContext(ctx, traceContextKey, string(traceContextBinary))
+}
+
+// TagRPC creates a new trace span for the server side of the RPC.
+//
+// It checks the incoming gRPC metadata in ctx for a SpanContext, and if
+// it finds one, uses that SpanContext as the parent context of the new span.
+//
+// It returns ctx, with the new trace span added.
+func (s *ServerHandler) traceTagRPC(ctx context.Context, rti *stats.RPCTagInfo) context.Context {
+	md, _ := metadata.FromIncomingContext(ctx)
+	name := strings.TrimPrefix(rti.FullMethodName, "/")
+	name = strings.Replace(name, "/", ".", -1)
+	traceContext := md[traceContextKey]
+	var (
+		parent     trace.SpanContext
+		haveParent bool
+	)
+	if len(traceContext) > 0 {
+		// Metadata with keys ending in -bin are actually binary. They are base64
+		// encoded before being put on the wire, see:
+		// https://github.com/grpc/grpc-go/blob/08d6261/Documentation/grpc-metadata.md#storing-binary-data-in-metadata
+		traceContextBinary := []byte(traceContext[0])
+		parent, haveParent = propagation.FromBinary(traceContextBinary)
+		if haveParent && !s.IsPublicEndpoint {
+			ctx, _ := trace.StartSpanWithRemoteParent(ctx, name, parent,
+				trace.WithSpanKind(trace.SpanKindServer),
+				trace.WithSampler(s.StartOptions.Sampler),
+			)
+			return ctx
+		}
+	}
+	ctx, span := trace.StartSpan(ctx, name,
+		trace.WithSpanKind(trace.SpanKindServer),
+		trace.WithSampler(s.StartOptions.Sampler))
+	if haveParent {
+		span.AddLink(trace.Link{TraceID: parent.TraceID, SpanID: parent.SpanID, Type: trace.LinkTypeChild})
+	}
+	return ctx
+}
+
+func traceHandleRPC(ctx context.Context, rs stats.RPCStats) {
+	span := trace.FromContext(ctx)
+	// TODO: compressed and uncompressed sizes are not populated in every message.
+	switch rs := rs.(type) {
+	case *stats.Begin:
+		span.AddAttributes(
+			trace.BoolAttribute("Client", rs.Client),
+			trace.BoolAttribute("FailFast", rs.FailFast))
+	case *stats.InPayload:
+		span.AddMessageReceiveEvent(0 /* TODO: messageID */, int64(rs.Length), int64(rs.WireLength))
+	case *stats.OutPayload:
+		span.AddMessageSendEvent(0, int64(rs.Length), int64(rs.WireLength))
+	case *stats.End:
+		if rs.Error != nil {
+			s, ok := status.FromError(rs.Error)
+			if ok {
+				span.SetStatus(trace.Status{Code: int32(s.Code()), Message: s.Message()})
+			} else {
+				span.SetStatus(trace.Status{Code: int32(codes.Internal), Message: rs.Error.Error()})
+			}
+		}
+		span.End()
+	}
+}

vendor/google.golang.org/api/transport/grpc/dial.go

@@ -0,0 +1,298 @@
+// Copyright 2015 Google LLC.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package grpc supports network connections to GRPC servers.
+// This package is not intended for use by end developers. Use the
+// google.golang.org/api/option package to configure API clients.
+package grpc
+
+import (
+	"context"
+	"crypto/tls"
+	"errors"
+	"log"
+	"strings"
+
+	"cloud.google.com/go/compute/metadata"
+	"go.opencensus.io/plugin/ocgrpc"
+	"golang.org/x/oauth2"
+	"google.golang.org/api/internal"
+	"google.golang.org/api/option"
+	"google.golang.org/api/transport/internal/dca"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+	grpcgoogle "google.golang.org/grpc/credentials/google"
+	"google.golang.org/grpc/credentials/oauth"
+
+	// Install grpclb, which is required for direct path.
+	_ "google.golang.org/grpc/balancer/grpclb"
+)
+
+// Set at init time by dial_appengine.go. If nil, we're not on App Engine.
+var appengineDialerHook func(context.Context) grpc.DialOption
+
+// Set at init time by dial_socketopt.go. If nil, socketopt is not supported.
+var timeoutDialerOption grpc.DialOption
+
+// Dial returns a GRPC connection for use communicating with a Google cloud
+// service, configured with the given ClientOptions.
+func Dial(ctx context.Context, opts ...option.ClientOption) (*grpc.ClientConn, error) {
+	o, err := processAndValidateOpts(opts)
+	if err != nil {
+		return nil, err
+	}
+	if o.GRPCConnPool != nil {
+		return o.GRPCConnPool.Conn(), nil
+	}
+	// NOTE(cbro): We removed support for option.WithGRPCConnPool (GRPCConnPoolSize)
+	// on 2020-02-12 because RoundRobin and WithBalancer are deprecated and we need to remove usages of it.
+	//
+	// Connection pooling is only done via DialPool.
+	return dial(ctx, false, o)
+}
+
+// DialInsecure returns an insecure GRPC connection for use communicating
+// with fake or mock Google cloud service implementations, such as emulators.
+// The connection is configured with the given ClientOptions.
+func DialInsecure(ctx context.Context, opts ...option.ClientOption) (*grpc.ClientConn, error) {
+	o, err := processAndValidateOpts(opts)
+	if err != nil {
+		return nil, err
+	}
+	return dial(ctx, true, o)
+}
+
+// DialPool returns a pool of GRPC connections for the given service.
+// This differs from the connection pooling implementation used by Dial, which uses a custom GRPC load balancer.
+// DialPool should be used instead of Dial when a pool is used by default or a different custom GRPC load balancer is needed.
+// The context and options are shared between each Conn in the pool.
+// The pool size is configured using the WithGRPCConnectionPool option.
+//
+// This API is subject to change as we further refine requirements. It will go away if gRPC stubs accept an interface instead of the concrete ClientConn type. See https://github.com/grpc/grpc-go/issues/1287.
+func DialPool(ctx context.Context, opts ...option.ClientOption) (ConnPool, error) {
+	o, err := processAndValidateOpts(opts)
+	if err != nil {
+		return nil, err
+	}
+	if o.GRPCConnPool != nil {
+		return o.GRPCConnPool, nil
+	}
+	poolSize := o.GRPCConnPoolSize
+	if o.GRPCConn != nil {
+		// WithGRPCConn is technically incompatible with WithGRPCConnectionPool.
+		// Always assume pool size is 1 when a grpc.ClientConn is explicitly used.
+		poolSize = 1
+	}
+	o.GRPCConnPoolSize = 0 // we don't *need* to set this to zero, but it's safe to.
+
+	if poolSize == 0 || poolSize == 1 {
+		// Fast path for common case for a connection pool with a single connection.
+		conn, err := dial(ctx, false, o)
+		if err != nil {
+			return nil, err
+		}
+		return &singleConnPool{conn}, nil
+	}
+
+	pool := &roundRobinConnPool{}
+	for i := 0; i < poolSize; i++ {
+		conn, err := dial(ctx, false, o)
+		if err != nil {
+			defer pool.Close() // NOTE: error from Close is ignored.
+			return nil, err
+		}
+		pool.conns = append(pool.conns, conn)
+	}
+	return pool, nil
+}
+
+func dial(ctx context.Context, insecure bool, o *internal.DialSettings) (*grpc.ClientConn, error) {
+	if o.HTTPClient != nil {
+		return nil, errors.New("unsupported HTTP client specified")
+	}
+	if o.GRPCConn != nil {
+		return o.GRPCConn, nil
+	}
+	clientCertSource, endpoint, err := dca.GetClientCertificateSourceAndEndpoint(o)
+	if err != nil {
+		return nil, err
+	}
+	var grpcOpts []grpc.DialOption
+	if insecure {
+		grpcOpts = []grpc.DialOption{grpc.WithInsecure()}
+	} else if !o.NoAuth {
+		if o.APIKey != "" {
+			log.Print("API keys are not supported for gRPC APIs. Remove the WithAPIKey option from your client-creating call.")
+		}
+		creds, err := internal.Creds(ctx, o)
+		if err != nil {
+			return nil, err
+		}
+
+		if o.QuotaProject == "" {
+			o.QuotaProject = internal.QuotaProjectFromCreds(creds)
+		}
+
+		// Attempt Direct Path only if:
+		// * The endpoint is a host:port (or dns:///host:port).
+		// * Credentials are obtained via GCE metadata server, using the default
+		//   service account.
+		if o.EnableDirectPath && checkDirectPathEndPoint(endpoint) && isTokenSourceDirectPathCompatible(creds.TokenSource, o) && metadata.OnGCE() {
+			if !strings.HasPrefix(endpoint, "dns:///") {
+				endpoint = "dns:///" + endpoint
+			}
+			grpcOpts = []grpc.DialOption{
+				grpc.WithCredentialsBundle(
+					grpcgoogle.NewComputeEngineCredentials(),
+				),
+				// For now all DirectPath go clients will be using the following lb config, but in future
+				// when different services need different configs, then we should change this to a
+				// per-service config.
+				grpc.WithDisableServiceConfig(),
+				grpc.WithDefaultServiceConfig(`{"loadBalancingConfig":[{"grpclb":{"childPolicy":[{"pick_first":{}}]}}]}`),
+			}
+			// TODO(cbro): add support for system parameters (quota project, request reason) via chained interceptor.
+		} else {
+			tlsConfig := &tls.Config{
+				GetClientCertificate: clientCertSource,
+			}
+			grpcOpts = []grpc.DialOption{
+				grpc.WithPerRPCCredentials(grpcTokenSource{
+					TokenSource:   oauth.TokenSource{creds.TokenSource},
+					quotaProject:  o.QuotaProject,
+					requestReason: o.RequestReason,
+				}),
+				grpc.WithTransportCredentials(credentials.NewTLS(tlsConfig)),
+			}
+		}
+	}
+
+	if appengineDialerHook != nil {
+		// Use the Socket API on App Engine.
+		// appengine dialer will override socketopt dialer
+		grpcOpts = append(grpcOpts, appengineDialerHook(ctx))
+	}
+
+	// Add tracing, but before the other options, so that clients can override the
+	// gRPC stats handler.
+	// This assumes that gRPC options are processed in order, left to right.
+	grpcOpts = addOCStatsHandler(grpcOpts, o)
+	grpcOpts = append(grpcOpts, o.GRPCDialOpts...)
+	if o.UserAgent != "" {
+		grpcOpts = append(grpcOpts, grpc.WithUserAgent(o.UserAgent))
+	}
+
+	// TODO(weiranf): This socketopt dialer will be used by default at some
+	// point when isDirectPathEnabled will default to true, we guard it by
+	// the Directpath env var for now once we can introspect user defined
+	// dialer (https://github.com/grpc/grpc-go/issues/2795).
+	if timeoutDialerOption != nil && o.EnableDirectPath && checkDirectPathEndPoint(endpoint) && metadata.OnGCE() {
+		grpcOpts = append(grpcOpts, timeoutDialerOption)
+	}
+
+	return grpc.DialContext(ctx, endpoint, grpcOpts...)
+}
+
+func addOCStatsHandler(opts []grpc.DialOption, settings *internal.DialSettings) []grpc.DialOption {
+	if settings.TelemetryDisabled {
+		return opts
+	}
+	return append(opts, grpc.WithStatsHandler(&ocgrpc.ClientHandler{}))
+}
+
+// grpcTokenSource supplies PerRPCCredentials from an oauth.TokenSource.
+type grpcTokenSource struct {
+	oauth.TokenSource
+
+	// Additional metadata attached as headers.
+	quotaProject  string
+	requestReason string
+}
+
+// GetRequestMetadata gets the request metadata as a map from a grpcTokenSource.
+func (ts grpcTokenSource) GetRequestMetadata(ctx context.Context, uri ...string) (
+	map[string]string, error) {
+	metadata, err := ts.TokenSource.GetRequestMetadata(ctx, uri...)
+	if err != nil {
+		return nil, err
+	}
+
+	// Attach system parameter
+	if ts.quotaProject != "" {
+		metadata["X-goog-user-project"] = ts.quotaProject
+	}
+	if ts.requestReason != "" {
+		metadata["X-goog-request-reason"] = ts.requestReason
+	}
+	return metadata, nil
+}
+
+func isTokenSourceDirectPathCompatible(ts oauth2.TokenSource, o *internal.DialSettings) bool {
+	if ts == nil {
+		return false
+	}
+	tok, err := ts.Token()
+	if err != nil {
+		return false
+	}
+	if tok == nil {
+		return false
+	}
+	if o.AllowNonDefaultServiceAccount {
+		return true
+	}
+	if source, _ := tok.Extra("oauth2.google.tokenSource").(string); source != "compute-metadata" {
+		return false
+	}
+	if acct, _ := tok.Extra("oauth2.google.serviceAccount").(string); acct != "default" {
+		return false
+	}
+	return true
+}
+
+func checkDirectPathEndPoint(endpoint string) bool {
+	// Only [dns:///]host[:port] is supported, not other schemes (e.g., "tcp://" or "unix://").
+	// Also don't try direct path if the user has chosen an alternate name resolver
+	// (i.e., via ":///" prefix).
+	//
+	// TODO(cbro): once gRPC has introspectible options, check the user hasn't
+	// provided a custom dialer in gRPC options.
+	if strings.Contains(endpoint, "://") && !strings.HasPrefix(endpoint, "dns:///") {
+		return false
+	}
+
+	if endpoint == "" {
+		return false
+	}
+
+	return true
+}
+
+func processAndValidateOpts(opts []option.ClientOption) (*internal.DialSettings, error) {
+	var o internal.DialSettings
+	for _, opt := range opts {
+		opt.Apply(&o)
+	}
+	if err := o.Validate(); err != nil {
+		return nil, err
+	}
+
+	return &o, nil
+}
+
+type connPoolOption struct{ ConnPool }
+
+// WithConnPool returns a ClientOption that specifies the ConnPool
+// connection to use as the basis of communications.
+//
+// This is only to be used by Google client libraries internally, for example
+// when creating a longrunning API client that shares the same connection pool
+// as a service client.
+func WithConnPool(p ConnPool) option.ClientOption {
+	return connPoolOption{p}
+}
+
+func (o connPoolOption) Apply(s *internal.DialSettings) {
+	s.GRPCConnPool = o.ConnPool
+}

vendor/google.golang.org/api/transport/grpc/dial_appengine.go

@@ -0,0 +1,32 @@
+// Copyright 2016 Google LLC.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build appengine
+// +build appengine
+
+package grpc
+
+import (
+	"context"
+	"net"
+	"time"
+
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/socket"
+	"google.golang.org/grpc"
+)
+
+func init() {
+	// NOTE: dev_appserver doesn't currently support SSL.
+	// When it does, this code can be removed.
+	if appengine.IsDevAppServer() {
+		return
+	}
+
+	appengineDialerHook = func(ctx context.Context) grpc.DialOption {
+		return grpc.WithDialer(func(addr string, timeout time.Duration) (net.Conn, error) {
+			return socket.DialTimeout(ctx, "tcp", addr, timeout)
+		})
+	}
+}

vendor/google.golang.org/api/transport/grpc/dial_socketopt.go

@@ -0,0 +1,50 @@
+// Copyright 2019 Google LLC.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.11 && linux
+// +build go1.11,linux
+
+package grpc
+
+import (
+	"context"
+	"net"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+	"google.golang.org/grpc"
+)
+
+const (
+	// defaultTCPUserTimeout is the default TCP_USER_TIMEOUT socket option. By
+	// default is 20 seconds.
+	tcpUserTimeoutMilliseconds = 20000
+)
+
+func init() {
+	// timeoutDialerOption is a grpc.DialOption that contains dialer with
+	// socket option TCP_USER_TIMEOUT. This dialer requires go versions 1.11+.
+	timeoutDialerOption = grpc.WithContextDialer(dialTCPUserTimeout)
+}
+
+func dialTCPUserTimeout(ctx context.Context, addr string) (net.Conn, error) {
+	control := func(network, address string, c syscall.RawConn) error {
+		var syscallErr error
+		controlErr := c.Control(func(fd uintptr) {
+			syscallErr = syscall.SetsockoptInt(
+				int(fd), syscall.IPPROTO_TCP, unix.TCP_USER_TIMEOUT, tcpUserTimeoutMilliseconds)
+		})
+		if syscallErr != nil {
+			return syscallErr
+		}
+		if controlErr != nil {
+			return controlErr
+		}
+		return nil
+	}
+	d := &net.Dialer{
+		Control: control,
+	}
+	return d.DialContext(ctx, "tcp", addr)
+}

vendor/google.golang.org/api/transport/grpc/pool.go

@@ -0,0 +1,92 @@
+// Copyright 2020 Google LLC.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package grpc
+
+import (
+	"context"
+	"fmt"
+	"sync/atomic"
+
+	"google.golang.org/api/internal"
+	"google.golang.org/grpc"
+)
+
+// ConnPool is a pool of grpc.ClientConns.
+type ConnPool = internal.ConnPool // NOTE(cbro): type alias to export the type. It must live in internal to avoid a circular dependency.
+
+var _ ConnPool = &roundRobinConnPool{}
+var _ ConnPool = &singleConnPool{}
+
+// singleConnPool is a special case for a single connection.
+type singleConnPool struct {
+	*grpc.ClientConn
+}
+
+func (p *singleConnPool) Conn() *grpc.ClientConn { return p.ClientConn }
+func (p *singleConnPool) Num() int               { return 1 }
+
+type roundRobinConnPool struct {
+	conns []*grpc.ClientConn
+
+	idx uint32 // access via sync/atomic
+}
+
+func (p *roundRobinConnPool) Num() int {
+	return len(p.conns)
+}
+
+func (p *roundRobinConnPool) Conn() *grpc.ClientConn {
+	i := atomic.AddUint32(&p.idx, 1)
+	return p.conns[i%uint32(len(p.conns))]
+}
+
+func (p *roundRobinConnPool) Close() error {
+	var errs multiError
+	for _, conn := range p.conns {
+		if err := conn.Close(); err != nil {
+			errs = append(errs, err)
+		}
+	}
+	if len(errs) == 0 {
+		return nil
+	}
+	return errs
+}
+
+func (p *roundRobinConnPool) Invoke(ctx context.Context, method string, args interface{}, reply interface{}, opts ...grpc.CallOption) error {
+	return p.Conn().Invoke(ctx, method, args, reply, opts...)
+}
+
+func (p *roundRobinConnPool) NewStream(ctx context.Context, desc *grpc.StreamDesc, method string, opts ...grpc.CallOption) (grpc.ClientStream, error) {
+	return p.Conn().NewStream(ctx, desc, method, opts...)
+}
+
+// multiError represents errors from multiple conns in the group.
+//
+// TODO: figure out how and whether this is useful to export. End users should
+// not be depending on the transport/grpc package directly, so there might need
+// to be some service-specific multi-error type.
+type multiError []error
+
+func (m multiError) Error() string {
+	s, n := "", 0
+	for _, e := range m {
+		if e != nil {
+			if n == 0 {
+				s = e.Error()
+			}
+			n++
+		}
+	}
+	switch n {
+	case 0:
+		return "(0 errors)"
+	case 1:
+		return s
+	case 2:
+		return s + " (and 1 other error)"
+	}
+	return fmt.Sprintf("%s (and %d other errors)", s, n-1)
+}

vendor/google.golang.org/appengine/internal/socket/socket_service.proto

@@ -0,0 +1,460 @@
+syntax = "proto2";
+option go_package = "socket";
+
+package appengine;
+
+message RemoteSocketServiceError {
+  enum ErrorCode {
+    SYSTEM_ERROR = 1;
+    GAI_ERROR = 2;
+    FAILURE = 4;
+    PERMISSION_DENIED = 5;
+    INVALID_REQUEST = 6;
+    SOCKET_CLOSED = 7;
+  }
+
+  enum SystemError {
+    option allow_alias = true;
+
+    SYS_SUCCESS = 0;
+    SYS_EPERM = 1;
+    SYS_ENOENT = 2;
+    SYS_ESRCH = 3;
+    SYS_EINTR = 4;
+    SYS_EIO = 5;
+    SYS_ENXIO = 6;
+    SYS_E2BIG = 7;
+    SYS_ENOEXEC = 8;
+    SYS_EBADF = 9;
+    SYS_ECHILD = 10;
+    SYS_EAGAIN = 11;
+    SYS_EWOULDBLOCK = 11;
+    SYS_ENOMEM = 12;
+    SYS_EACCES = 13;
+    SYS_EFAULT = 14;
+    SYS_ENOTBLK = 15;
+    SYS_EBUSY = 16;
+    SYS_EEXIST = 17;
+    SYS_EXDEV = 18;
+    SYS_ENODEV = 19;
+    SYS_ENOTDIR = 20;
+    SYS_EISDIR = 21;
+    SYS_EINVAL = 22;
+    SYS_ENFILE = 23;
+    SYS_EMFILE = 24;
+    SYS_ENOTTY = 25;
+    SYS_ETXTBSY = 26;
+    SYS_EFBIG = 27;
+    SYS_ENOSPC = 28;
+    SYS_ESPIPE = 29;
+    SYS_EROFS = 30;
+    SYS_EMLINK = 31;
+    SYS_EPIPE = 32;
+    SYS_EDOM = 33;
+    SYS_ERANGE = 34;
+    SYS_EDEADLK = 35;
+    SYS_EDEADLOCK = 35;
+    SYS_ENAMETOOLONG = 36;
+    SYS_ENOLCK = 37;
+    SYS_ENOSYS = 38;
+    SYS_ENOTEMPTY = 39;
+    SYS_ELOOP = 40;
+    SYS_ENOMSG = 42;
+    SYS_EIDRM = 43;
+    SYS_ECHRNG = 44;
+    SYS_EL2NSYNC = 45;
+    SYS_EL3HLT = 46;
+    SYS_EL3RST = 47;
+    SYS_ELNRNG = 48;
+    SYS_EUNATCH = 49;
+    SYS_ENOCSI = 50;
+    SYS_EL2HLT = 51;
+    SYS_EBADE = 52;
+    SYS_EBADR = 53;
+    SYS_EXFULL = 54;
+    SYS_ENOANO = 55;
+    SYS_EBADRQC = 56;
+    SYS_EBADSLT = 57;
+    SYS_EBFONT = 59;
+    SYS_ENOSTR = 60;
+    SYS_ENODATA = 61;
+    SYS_ETIME = 62;
+    SYS_ENOSR = 63;
+    SYS_ENONET = 64;
+    SYS_ENOPKG = 65;
+    SYS_EREMOTE = 66;
+    SYS_ENOLINK = 67;
+    SYS_EADV = 68;
+    SYS_ESRMNT = 69;
+    SYS_ECOMM = 70;
+    SYS_EPROTO = 71;
+    SYS_EMULTIHOP = 72;
+    SYS_EDOTDOT = 73;
+    SYS_EBADMSG = 74;
+    SYS_EOVERFLOW = 75;
+    SYS_ENOTUNIQ = 76;
+    SYS_EBADFD = 77;
+    SYS_EREMCHG = 78;
+    SYS_ELIBACC = 79;
+    SYS_ELIBBAD = 80;
+    SYS_ELIBSCN = 81;
+    SYS_ELIBMAX = 82;
+    SYS_ELIBEXEC = 83;
+    SYS_EILSEQ = 84;
+    SYS_ERESTART = 85;
+    SYS_ESTRPIPE = 86;
+    SYS_EUSERS = 87;
+    SYS_ENOTSOCK = 88;
+    SYS_EDESTADDRREQ = 89;
+    SYS_EMSGSIZE = 90;
+    SYS_EPROTOTYPE = 91;
+    SYS_ENOPROTOOPT = 92;
+    SYS_EPROTONOSUPPORT = 93;
+    SYS_ESOCKTNOSUPPORT = 94;
+    SYS_EOPNOTSUPP = 95;
+    SYS_ENOTSUP = 95;
+    SYS_EPFNOSUPPORT = 96;
+    SYS_EAFNOSUPPORT = 97;
+    SYS_EADDRINUSE = 98;
+    SYS_EADDRNOTAVAIL = 99;
+    SYS_ENETDOWN = 100;
+    SYS_ENETUNREACH = 101;
+    SYS_ENETRESET = 102;
+    SYS_ECONNABORTED = 103;
+    SYS_ECONNRESET = 104;
+    SYS_ENOBUFS = 105;
+    SYS_EISCONN = 106;
+    SYS_ENOTCONN = 107;
+    SYS_ESHUTDOWN = 108;
+    SYS_ETOOMANYREFS = 109;
+    SYS_ETIMEDOUT = 110;
+    SYS_ECONNREFUSED = 111;
+    SYS_EHOSTDOWN = 112;
+    SYS_EHOSTUNREACH = 113;
+    SYS_EALREADY = 114;
+    SYS_EINPROGRESS = 115;
+    SYS_ESTALE = 116;
+    SYS_EUCLEAN = 117;
+    SYS_ENOTNAM = 118;
+    SYS_ENAVAIL = 119;
+    SYS_EISNAM = 120;
+    SYS_EREMOTEIO = 121;
+    SYS_EDQUOT = 122;
+    SYS_ENOMEDIUM = 123;
+    SYS_EMEDIUMTYPE = 124;
+    SYS_ECANCELED = 125;
+    SYS_ENOKEY = 126;
+    SYS_EKEYEXPIRED = 127;
+    SYS_EKEYREVOKED = 128;
+    SYS_EKEYREJECTED = 129;
+    SYS_EOWNERDEAD = 130;
+    SYS_ENOTRECOVERABLE = 131;
+    SYS_ERFKILL = 132;
+  }
+
+  optional int32 system_error = 1 [default=0];
+  optional string error_detail = 2;
+}
+
+message AddressPort {
+  required int32 port = 1;
+  optional bytes packed_address = 2;
+
+  optional string hostname_hint = 3;
+}
+
+
+
+message CreateSocketRequest {
+  enum SocketFamily {
+    IPv4 = 1;
+    IPv6 = 2;
+  }
+
+  enum SocketProtocol {
+    TCP = 1;
+    UDP = 2;
+  }
+
+  required SocketFamily family = 1;
+  required SocketProtocol protocol = 2;
+
+  repeated SocketOption socket_options = 3;
+
+  optional AddressPort proxy_external_ip = 4;
+
+  optional int32 listen_backlog = 5 [default=0];
+
+  optional AddressPort remote_ip = 6;
+
+  optional string app_id = 9;
+
+  optional int64 project_id = 10;
+}
+
+message CreateSocketReply {
+  optional string socket_descriptor = 1;
+
+  optional AddressPort server_address = 3;
+
+  optional AddressPort proxy_external_ip = 4;
+
+  extensions 1000 to max;
+}
+
+
+
+message BindRequest {
+  required string socket_descriptor = 1;
+  required AddressPort proxy_external_ip = 2;
+}
+
+message BindReply {
+  optional AddressPort proxy_external_ip = 1;
+}
+
+
+
+message GetSocketNameRequest {
+  required string socket_descriptor = 1;
+}
+
+message GetSocketNameReply {
+  optional AddressPort proxy_external_ip = 2;
+}
+
+
+
+message GetPeerNameRequest {
+  required string socket_descriptor = 1;
+}
+
+message GetPeerNameReply {
+  optional AddressPort peer_ip = 2;
+}
+
+
+message SocketOption {
+
+  enum SocketOptionLevel {
+    SOCKET_SOL_IP = 0;
+    SOCKET_SOL_SOCKET = 1;
+    SOCKET_SOL_TCP = 6;
+    SOCKET_SOL_UDP = 17;
+  }
+
+  enum SocketOptionName {
+    option allow_alias = true;
+
+    SOCKET_SO_DEBUG = 1;
+    SOCKET_SO_REUSEADDR = 2;
+    SOCKET_SO_TYPE = 3;
+    SOCKET_SO_ERROR = 4;
+    SOCKET_SO_DONTROUTE = 5;
+    SOCKET_SO_BROADCAST = 6;
+    SOCKET_SO_SNDBUF = 7;
+    SOCKET_SO_RCVBUF = 8;
+    SOCKET_SO_KEEPALIVE = 9;
+    SOCKET_SO_OOBINLINE = 10;
+    SOCKET_SO_LINGER = 13;
+    SOCKET_SO_RCVTIMEO = 20;
+    SOCKET_SO_SNDTIMEO = 21;
+
+    SOCKET_IP_TOS = 1;
+    SOCKET_IP_TTL = 2;
+    SOCKET_IP_HDRINCL = 3;
+    SOCKET_IP_OPTIONS = 4;
+
+    SOCKET_TCP_NODELAY = 1;
+    SOCKET_TCP_MAXSEG = 2;
+    SOCKET_TCP_CORK = 3;
+    SOCKET_TCP_KEEPIDLE = 4;
+    SOCKET_TCP_KEEPINTVL = 5;
+    SOCKET_TCP_KEEPCNT = 6;
+    SOCKET_TCP_SYNCNT = 7;
+    SOCKET_TCP_LINGER2 = 8;
+    SOCKET_TCP_DEFER_ACCEPT = 9;
+    SOCKET_TCP_WINDOW_CLAMP = 10;
+    SOCKET_TCP_INFO = 11;
+    SOCKET_TCP_QUICKACK = 12;
+  }
+
+  required SocketOptionLevel level = 1;
+  required SocketOptionName option = 2;
+  required bytes value = 3;
+}
+
+
+message SetSocketOptionsRequest {
+  required string socket_descriptor = 1;
+  repeated SocketOption options = 2;
+}
+
+message SetSocketOptionsReply {
+}
+
+message GetSocketOptionsRequest {
+  required string socket_descriptor = 1;
+  repeated SocketOption options = 2;
+}
+
+message GetSocketOptionsReply {
+  repeated SocketOption options = 2;
+}
+
+
+message ConnectRequest {
+  required string socket_descriptor = 1;
+  required AddressPort remote_ip = 2;
+  optional double timeout_seconds = 3 [default=-1];
+}
+
+message ConnectReply {
+  optional AddressPort proxy_external_ip = 1;
+
+  extensions 1000 to max;
+}
+
+
+message ListenRequest {
+  required string socket_descriptor = 1;
+  required int32 backlog = 2;
+}
+
+message ListenReply {
+}
+
+
+message AcceptRequest {
+  required string socket_descriptor = 1;
+  optional double timeout_seconds = 2 [default=-1];
+}
+
+message AcceptReply {
+  optional bytes new_socket_descriptor = 2;
+  optional AddressPort remote_address = 3;
+}
+
+
+
+message ShutDownRequest {
+  enum How {
+    SOCKET_SHUT_RD = 1;
+    SOCKET_SHUT_WR = 2;
+    SOCKET_SHUT_RDWR = 3;
+  }
+  required string socket_descriptor = 1;
+  required How how = 2;
+  required int64 send_offset = 3;
+}
+
+message ShutDownReply {
+}
+
+
+
+message CloseRequest {
+  required string socket_descriptor = 1;
+  optional int64 send_offset = 2 [default=-1];
+}
+
+message CloseReply {
+}
+
+
+
+message SendRequest {
+  required string socket_descriptor = 1;
+  required bytes data = 2 [ctype=CORD];
+  required int64 stream_offset = 3;
+  optional int32 flags = 4 [default=0];
+  optional AddressPort send_to = 5;
+  optional double timeout_seconds = 6 [default=-1];
+}
+
+message SendReply {
+  optional int32 data_sent = 1;
+}
+
+
+message ReceiveRequest {
+  enum Flags {
+    MSG_OOB = 1;
+    MSG_PEEK = 2;
+  }
+  required string socket_descriptor = 1;
+  required int32 data_size = 2;
+  optional int32 flags = 3 [default=0];
+  optional double timeout_seconds = 5 [default=-1];
+}
+
+message ReceiveReply {
+  optional int64 stream_offset = 2;
+  optional bytes data = 3 [ctype=CORD];
+  optional AddressPort received_from = 4;
+  optional int32 buffer_size = 5;
+}
+
+
+
+message PollEvent {
+
+  enum PollEventFlag {
+    SOCKET_POLLNONE = 0;
+    SOCKET_POLLIN = 1;
+    SOCKET_POLLPRI = 2;
+    SOCKET_POLLOUT = 4;
+    SOCKET_POLLERR = 8;
+    SOCKET_POLLHUP = 16;
+    SOCKET_POLLNVAL = 32;
+    SOCKET_POLLRDNORM = 64;
+    SOCKET_POLLRDBAND = 128;
+    SOCKET_POLLWRNORM = 256;
+    SOCKET_POLLWRBAND = 512;
+    SOCKET_POLLMSG = 1024;
+    SOCKET_POLLREMOVE = 4096;
+    SOCKET_POLLRDHUP = 8192;
+  };
+
+  required string socket_descriptor = 1;
+  required int32 requested_events = 2;
+  required int32 observed_events = 3;
+}
+
+message PollRequest {
+  repeated PollEvent events = 1;
+  optional double timeout_seconds = 2 [default=-1];
+}
+
+message PollReply {
+  repeated PollEvent events = 2;
+}
+
+message ResolveRequest {
+  required string name = 1;
+  repeated CreateSocketRequest.SocketFamily address_families = 2;
+}
+
+message ResolveReply {
+  enum ErrorCode {
+    SOCKET_EAI_ADDRFAMILY = 1;
+    SOCKET_EAI_AGAIN = 2;
+    SOCKET_EAI_BADFLAGS = 3;
+    SOCKET_EAI_FAIL = 4;
+    SOCKET_EAI_FAMILY = 5;
+    SOCKET_EAI_MEMORY = 6;
+    SOCKET_EAI_NODATA = 7;
+    SOCKET_EAI_NONAME = 8;
+    SOCKET_EAI_SERVICE = 9;
+    SOCKET_EAI_SOCKTYPE = 10;
+    SOCKET_EAI_SYSTEM = 11;
+    SOCKET_EAI_BADHINTS = 12;
+    SOCKET_EAI_PROTOCOL = 13;
+    SOCKET_EAI_OVERFLOW = 14;
+    SOCKET_EAI_MAX = 15;
+  };
+
+  repeated bytes packed_address = 2;
+  optional string canonical_name = 3;
+  repeated string aliases = 4;
+}

vendor/google.golang.org/appengine/socket/doc.go

@@ -0,0 +1,10 @@
+// Copyright 2012 Google Inc. All rights reserved.
+// Use of this source code is governed by the Apache 2.0
+// license that can be found in the LICENSE file.
+
+// Package socket provides outbound network sockets.
+//
+// This package is only required in the classic App Engine environment.
+// Applications running only in App Engine "flexible environment" should
+// use the standard library's net package.
+package socket

vendor/google.golang.org/appengine/socket/socket_classic.go

@@ -0,0 +1,290 @@
+// Copyright 2012 Google Inc. All rights reserved.
+// Use of this source code is governed by the Apache 2.0
+// license that can be found in the LICENSE file.
+
+// +build appengine
+
+package socket
+
+import (
+	"fmt"
+	"io"
+	"net"
+	"strconv"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+	"golang.org/x/net/context"
+	"google.golang.org/appengine/internal"
+
+	pb "google.golang.org/appengine/internal/socket"
+)
+
+// Dial connects to the address addr on the network protocol.
+// The address format is host:port, where host may be a hostname or an IP address.
+// Known protocols are "tcp" and "udp".
+// The returned connection satisfies net.Conn, and is valid while ctx is valid;
+// if the connection is to be used after ctx becomes invalid, invoke SetContext
+// with the new context.
+func Dial(ctx context.Context, protocol, addr string) (*Conn, error) {
+	return DialTimeout(ctx, protocol, addr, 0)
+}
+
+var ipFamilies = []pb.CreateSocketRequest_SocketFamily{
+	pb.CreateSocketRequest_IPv4,
+	pb.CreateSocketRequest_IPv6,
+}
+
+// DialTimeout is like Dial but takes a timeout.
+// The timeout includes name resolution, if required.
+func DialTimeout(ctx context.Context, protocol, addr string, timeout time.Duration) (*Conn, error) {
+	dialCtx := ctx // Used for dialing and name resolution, but not stored in the *Conn.
+	if timeout > 0 {
+		var cancel context.CancelFunc
+		dialCtx, cancel = context.WithTimeout(ctx, timeout)
+		defer cancel()
+	}
+
+	host, portStr, err := net.SplitHostPort(addr)
+	if err != nil {
+		return nil, err
+	}
+	port, err := strconv.Atoi(portStr)
+	if err != nil {
+		return nil, fmt.Errorf("socket: bad port %q: %v", portStr, err)
+	}
+
+	var prot pb.CreateSocketRequest_SocketProtocol
+	switch protocol {
+	case "tcp":
+		prot = pb.CreateSocketRequest_TCP
+	case "udp":
+		prot = pb.CreateSocketRequest_UDP
+	default:
+		return nil, fmt.Errorf("socket: unknown protocol %q", protocol)
+	}
+
+	packedAddrs, resolved, err := resolve(dialCtx, ipFamilies, host)
+	if err != nil {
+		return nil, fmt.Errorf("socket: failed resolving %q: %v", host, err)
+	}
+	if len(packedAddrs) == 0 {
+		return nil, fmt.Errorf("no addresses for %q", host)
+	}
+
+	packedAddr := packedAddrs[0] // use first address
+	fam := pb.CreateSocketRequest_IPv4
+	if len(packedAddr) == net.IPv6len {
+		fam = pb.CreateSocketRequest_IPv6
+	}
+
+	req := &pb.CreateSocketRequest{
+		Family:   fam.Enum(),
+		Protocol: prot.Enum(),
+		RemoteIp: &pb.AddressPort{
+			Port:          proto.Int32(int32(port)),
+			PackedAddress: packedAddr,
+		},
+	}
+	if resolved {
+		req.RemoteIp.HostnameHint = &host
+	}
+	res := &pb.CreateSocketReply{}
+	if err := internal.Call(dialCtx, "remote_socket", "CreateSocket", req, res); err != nil {
+		return nil, err
+	}
+
+	return &Conn{
+		ctx:    ctx,
+		desc:   res.GetSocketDescriptor(),
+		prot:   prot,
+		local:  res.ProxyExternalIp,
+		remote: req.RemoteIp,
+	}, nil
+}
+
+// LookupIP returns the given host's IP addresses.
+func LookupIP(ctx context.Context, host string) (addrs []net.IP, err error) {
+	packedAddrs, _, err := resolve(ctx, ipFamilies, host)
+	if err != nil {
+		return nil, fmt.Errorf("socket: failed resolving %q: %v", host, err)
+	}
+	addrs = make([]net.IP, len(packedAddrs))
+	for i, pa := range packedAddrs {
+		addrs[i] = net.IP(pa)
+	}
+	return addrs, nil
+}
+
+func resolve(ctx context.Context, fams []pb.CreateSocketRequest_SocketFamily, host string) ([][]byte, bool, error) {
+	// Check if it's an IP address.
+	if ip := net.ParseIP(host); ip != nil {
+		if ip := ip.To4(); ip != nil {
+			return [][]byte{ip}, false, nil
+		}
+		return [][]byte{ip}, false, nil
+	}
+
+	req := &pb.ResolveRequest{
+		Name:            &host,
+		AddressFamilies: fams,
+	}
+	res := &pb.ResolveReply{}
+	if err := internal.Call(ctx, "remote_socket", "Resolve", req, res); err != nil {
+		// XXX: need to map to pb.ResolveReply_ErrorCode?
+		return nil, false, err
+	}
+	return res.PackedAddress, true, nil
+}
+
+// withDeadline is like context.WithDeadline, except it ignores the zero deadline.
+func withDeadline(parent context.Context, deadline time.Time) (context.Context, context.CancelFunc) {
+	if deadline.IsZero() {
+		return parent, func() {}
+	}
+	return context.WithDeadline(parent, deadline)
+}
+
+// Conn represents a socket connection.
+// It implements net.Conn.
+type Conn struct {
+	ctx    context.Context
+	desc   string
+	offset int64
+
+	prot          pb.CreateSocketRequest_SocketProtocol
+	local, remote *pb.AddressPort
+
+	readDeadline, writeDeadline time.Time // optional
+}
+
+// SetContext sets the context that is used by this Conn.
+// It is usually used only when using a Conn that was created in a different context,
+// such as when a connection is created during a warmup request but used while
+// servicing a user request.
+func (cn *Conn) SetContext(ctx context.Context) {
+	cn.ctx = ctx
+}
+
+func (cn *Conn) Read(b []byte) (n int, err error) {
+	const maxRead = 1 << 20
+	if len(b) > maxRead {
+		b = b[:maxRead]
+	}
+
+	req := &pb.ReceiveRequest{
+		SocketDescriptor: &cn.desc,
+		DataSize:         proto.Int32(int32(len(b))),
+	}
+	res := &pb.ReceiveReply{}
+	if !cn.readDeadline.IsZero() {
+		req.TimeoutSeconds = proto.Float64(cn.readDeadline.Sub(time.Now()).Seconds())
+	}
+	ctx, cancel := withDeadline(cn.ctx, cn.readDeadline)
+	defer cancel()
+	if err := internal.Call(ctx, "remote_socket", "Receive", req, res); err != nil {
+		return 0, err
+	}
+	if len(res.Data) == 0 {
+		return 0, io.EOF
+	}
+	if len(res.Data) > len(b) {
+		return 0, fmt.Errorf("socket: internal error: read too much data: %d > %d", len(res.Data), len(b))
+	}
+	return copy(b, res.Data), nil
+}
+
+func (cn *Conn) Write(b []byte) (n int, err error) {
+	const lim = 1 << 20 // max per chunk
+
+	for n < len(b) {
+		chunk := b[n:]
+		if len(chunk) > lim {
+			chunk = chunk[:lim]
+		}
+
+		req := &pb.SendRequest{
+			SocketDescriptor: &cn.desc,
+			Data:             chunk,
+			StreamOffset:     &cn.offset,
+		}
+		res := &pb.SendReply{}
+		if !cn.writeDeadline.IsZero() {
+			req.TimeoutSeconds = proto.Float64(cn.writeDeadline.Sub(time.Now()).Seconds())
+		}
+		ctx, cancel := withDeadline(cn.ctx, cn.writeDeadline)
+		defer cancel()
+		if err = internal.Call(ctx, "remote_socket", "Send", req, res); err != nil {
+			// assume zero bytes were sent in this RPC
+			break
+		}
+		n += int(res.GetDataSent())
+		cn.offset += int64(res.GetDataSent())
+	}
+
+	return
+}
+
+func (cn *Conn) Close() error {
+	req := &pb.CloseRequest{
+		SocketDescriptor: &cn.desc,
+	}
+	res := &pb.CloseReply{}
+	if err := internal.Call(cn.ctx, "remote_socket", "Close", req, res); err != nil {
+		return err
+	}
+	cn.desc = "CLOSED"
+	return nil
+}
+
+func addr(prot pb.CreateSocketRequest_SocketProtocol, ap *pb.AddressPort) net.Addr {
+	if ap == nil {
+		return nil
+	}
+	switch prot {
+	case pb.CreateSocketRequest_TCP:
+		return &net.TCPAddr{
+			IP:   net.IP(ap.PackedAddress),
+			Port: int(*ap.Port),
+		}
+	case pb.CreateSocketRequest_UDP:
+		return &net.UDPAddr{
+			IP:   net.IP(ap.PackedAddress),
+			Port: int(*ap.Port),
+		}
+	}
+	panic("unknown protocol " + prot.String())
+}
+
+func (cn *Conn) LocalAddr() net.Addr  { return addr(cn.prot, cn.local) }
+func (cn *Conn) RemoteAddr() net.Addr { return addr(cn.prot, cn.remote) }
+
+func (cn *Conn) SetDeadline(t time.Time) error {
+	cn.readDeadline = t
+	cn.writeDeadline = t
+	return nil
+}
+
+func (cn *Conn) SetReadDeadline(t time.Time) error {
+	cn.readDeadline = t
+	return nil
+}
+
+func (cn *Conn) SetWriteDeadline(t time.Time) error {
+	cn.writeDeadline = t
+	return nil
+}
+
+// KeepAlive signals that the connection is still in use.
+// It may be called to prevent the socket being closed due to inactivity.
+func (cn *Conn) KeepAlive() error {
+	req := &pb.GetSocketNameRequest{
+		SocketDescriptor: &cn.desc,
+	}
+	res := &pb.GetSocketNameReply{}
+	return internal.Call(cn.ctx, "remote_socket", "GetSocketName", req, res)
+}
+
+func init() {
+	internal.RegisterErrorCodeMap("remote_socket", pb.RemoteSocketServiceError_ErrorCode_name)
+}

vendor/google.golang.org/appengine/socket/socket_vm.go

@@ -0,0 +1,64 @@
+// Copyright 2015 Google Inc. All rights reserved.
+// Use of this source code is governed by the Apache 2.0
+// license that can be found in the LICENSE file.
+
+// +build !appengine
+
+package socket
+
+import (
+	"net"
+	"time"
+
+	"golang.org/x/net/context"
+)
+
+// Dial connects to the address addr on the network protocol.
+// The address format is host:port, where host may be a hostname or an IP address.
+// Known protocols are "tcp" and "udp".
+// The returned connection satisfies net.Conn, and is valid while ctx is valid;
+// if the connection is to be used after ctx becomes invalid, invoke SetContext
+// with the new context.
+func Dial(ctx context.Context, protocol, addr string) (*Conn, error) {
+	conn, err := net.Dial(protocol, addr)
+	if err != nil {
+		return nil, err
+	}
+	return &Conn{conn}, nil
+}
+
+// DialTimeout is like Dial but takes a timeout.
+// The timeout includes name resolution, if required.
+func DialTimeout(ctx context.Context, protocol, addr string, timeout time.Duration) (*Conn, error) {
+	conn, err := net.DialTimeout(protocol, addr, timeout)
+	if err != nil {
+		return nil, err
+	}
+	return &Conn{conn}, nil
+}
+
+// LookupIP returns the given host's IP addresses.
+func LookupIP(ctx context.Context, host string) (addrs []net.IP, err error) {
+	return net.LookupIP(host)
+}
+
+// Conn represents a socket connection.
+// It implements net.Conn.
+type Conn struct {
+	net.Conn
+}
+
+// SetContext sets the context that is used by this Conn.
+// It is usually used only when using a Conn that was created in a different context,
+// such as when a connection is created during a warmup request but used while
+// servicing a user request.
+func (cn *Conn) SetContext(ctx context.Context) {
+	// This function is not required in App Engine "flexible environment".
+}
+
+// KeepAlive signals that the connection is still in use.
+// It may be called to prevent the socket being closed due to inactivity.
+func (cn *Conn) KeepAlive() error {
+	// This function is not required in App Engine "flexible environment".
+	return nil
+}

vendor/google.golang.org/genproto/googleapis/type/date/date.pb.go

@@ -0,0 +1,200 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.26.0
+// 	protoc        v3.12.2
+// source: google/type/date.proto
+
+package date
+
+import (
+	reflect "reflect"
+	sync "sync"
+
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+// Represents a whole or partial calendar date, such as a birthday. The time of
+// day and time zone are either specified elsewhere or are insignificant. The
+// date is relative to the Gregorian Calendar. This can represent one of the
+// following:
+//
+// * A full date, with non-zero year, month, and day values
+// * A month and day value, with a zero year, such as an anniversary
+// * A year on its own, with zero month and day values
+// * A year and month value, with a zero day, such as a credit card expiration
+// date
+//
+// Related types are [google.type.TimeOfDay][google.type.TimeOfDay] and
+// `google.protobuf.Timestamp`.
+type Date struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// Year of the date. Must be from 1 to 9999, or 0 to specify a date without
+	// a year.
+	Year int32 `protobuf:"varint,1,opt,name=year,proto3" json:"year,omitempty"`
+	// Month of a year. Must be from 1 to 12, or 0 to specify a year without a
+	// month and day.
+	Month int32 `protobuf:"varint,2,opt,name=month,proto3" json:"month,omitempty"`
+	// Day of a month. Must be from 1 to 31 and valid for the year and month, or 0
+	// to specify a year by itself or a year and month where the day isn't
+	// significant.
+	Day int32 `protobuf:"varint,3,opt,name=day,proto3" json:"day,omitempty"`
+}
+
+func (x *Date) Reset() {
+	*x = Date{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_google_type_date_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *Date) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Date) ProtoMessage() {}
+
+func (x *Date) ProtoReflect() protoreflect.Message {
+	mi := &file_google_type_date_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use Date.ProtoReflect.Descriptor instead.
+func (*Date) Descriptor() ([]byte, []int) {
+	return file_google_type_date_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *Date) GetYear() int32 {
+	if x != nil {
+		return x.Year
+	}
+	return 0
+}
+
+func (x *Date) GetMonth() int32 {
+	if x != nil {
+		return x.Month
+	}
+	return 0
+}
+
+func (x *Date) GetDay() int32 {
+	if x != nil {
+		return x.Day
+	}
+	return 0
+}
+
+var File_google_type_date_proto protoreflect.FileDescriptor
+
+var file_google_type_date_proto_rawDesc = []byte{
+	0x0a, 0x16, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2f, 0x74, 0x79, 0x70, 0x65, 0x2f, 0x64, 0x61,
+	0x74, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x0b, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65,
+	0x2e, 0x74, 0x79, 0x70, 0x65, 0x22, 0x42, 0x0a, 0x04, 0x44, 0x61, 0x74, 0x65, 0x12, 0x12, 0x0a,
+	0x04, 0x79, 0x65, 0x61, 0x72, 0x18, 0x01, 0x20, 0x01, 0x28, 0x05, 0x52, 0x04, 0x79, 0x65, 0x61,
+	0x72, 0x12, 0x14, 0x0a, 0x05, 0x6d, 0x6f, 0x6e, 0x74, 0x68, 0x18, 0x02, 0x20, 0x01, 0x28, 0x05,
+	0x52, 0x05, 0x6d, 0x6f, 0x6e, 0x74, 0x68, 0x12, 0x10, 0x0a, 0x03, 0x64, 0x61, 0x79, 0x18, 0x03,
+	0x20, 0x01, 0x28, 0x05, 0x52, 0x03, 0x64, 0x61, 0x79, 0x42, 0x5d, 0x0a, 0x0f, 0x63, 0x6f, 0x6d,
+	0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x74, 0x79, 0x70, 0x65, 0x42, 0x09, 0x44, 0x61,
+	0x74, 0x65, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01, 0x5a, 0x34, 0x67, 0x6f, 0x6f, 0x67, 0x6c,
+	0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61, 0x6e, 0x67, 0x2e, 0x6f, 0x72, 0x67, 0x2f, 0x67, 0x65, 0x6e,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2f, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x61, 0x70, 0x69, 0x73,
+	0x2f, 0x74, 0x79, 0x70, 0x65, 0x2f, 0x64, 0x61, 0x74, 0x65, 0x3b, 0x64, 0x61, 0x74, 0x65, 0xf8,
+	0x01, 0x01, 0xa2, 0x02, 0x03, 0x47, 0x54, 0x50, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_google_type_date_proto_rawDescOnce sync.Once
+	file_google_type_date_proto_rawDescData = file_google_type_date_proto_rawDesc
+)
+
+func file_google_type_date_proto_rawDescGZIP() []byte {
+	file_google_type_date_proto_rawDescOnce.Do(func() {
+		file_google_type_date_proto_rawDescData = protoimpl.X.CompressGZIP(file_google_type_date_proto_rawDescData)
+	})
+	return file_google_type_date_proto_rawDescData
+}
+
+var file_google_type_date_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
+var file_google_type_date_proto_goTypes = []interface{}{
+	(*Date)(nil), // 0: google.type.Date
+}
+var file_google_type_date_proto_depIdxs = []int32{
+	0, // [0:0] is the sub-list for method output_type
+	0, // [0:0] is the sub-list for method input_type
+	0, // [0:0] is the sub-list for extension type_name
+	0, // [0:0] is the sub-list for extension extendee
+	0, // [0:0] is the sub-list for field type_name
+}
+
+func init() { file_google_type_date_proto_init() }
+func file_google_type_date_proto_init() {
+	if File_google_type_date_proto != nil {
+		return
+	}
+	if !protoimpl.UnsafeEnabled {
+		file_google_type_date_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*Date); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_google_type_date_proto_rawDesc,
+			NumEnums:      0,
+			NumMessages:   1,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_google_type_date_proto_goTypes,
+		DependencyIndexes: file_google_type_date_proto_depIdxs,
+		MessageInfos:      file_google_type_date_proto_msgTypes,
+	}.Build()
+	File_google_type_date_proto = out.File
+	file_google_type_date_proto_rawDesc = nil
+	file_google_type_date_proto_goTypes = nil
+	file_google_type_date_proto_depIdxs = nil
+}

vendor/google.golang.org/grpc/balancer/grpclb/grpc_lb_v1/load_balancer.pb.go

@@ -0,0 +1,960 @@
+// Copyright 2015 The gRPC Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// This file defines the GRPCLB LoadBalancing protocol.
+//
+// The canonical version of this proto can be found at
+// https://github.com/grpc/grpc-proto/blob/master/grpc/lb/v1/load_balancer.proto
+
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.25.0
+// 	protoc        v3.14.0
+// source: grpc/lb/v1/load_balancer.proto
+
+package grpc_lb_v1
+
+import (
+	proto "github.com/golang/protobuf/proto"
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	durationpb "google.golang.org/protobuf/types/known/durationpb"
+	timestamppb "google.golang.org/protobuf/types/known/timestamppb"
+	reflect "reflect"
+	sync "sync"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+// This is a compile-time assertion that a sufficiently up-to-date version
+// of the legacy proto package is being used.
+const _ = proto.ProtoPackageIsVersion4
+
+type LoadBalanceRequest struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// Types that are assignable to LoadBalanceRequestType:
+	//	*LoadBalanceRequest_InitialRequest
+	//	*LoadBalanceRequest_ClientStats
+	LoadBalanceRequestType isLoadBalanceRequest_LoadBalanceRequestType `protobuf_oneof:"load_balance_request_type"`
+}
+
+func (x *LoadBalanceRequest) Reset() {
+	*x = LoadBalanceRequest{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *LoadBalanceRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*LoadBalanceRequest) ProtoMessage() {}
+
+func (x *LoadBalanceRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use LoadBalanceRequest.ProtoReflect.Descriptor instead.
+func (*LoadBalanceRequest) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{0}
+}
+
+func (m *LoadBalanceRequest) GetLoadBalanceRequestType() isLoadBalanceRequest_LoadBalanceRequestType {
+	if m != nil {
+		return m.LoadBalanceRequestType
+	}
+	return nil
+}
+
+func (x *LoadBalanceRequest) GetInitialRequest() *InitialLoadBalanceRequest {
+	if x, ok := x.GetLoadBalanceRequestType().(*LoadBalanceRequest_InitialRequest); ok {
+		return x.InitialRequest
+	}
+	return nil
+}
+
+func (x *LoadBalanceRequest) GetClientStats() *ClientStats {
+	if x, ok := x.GetLoadBalanceRequestType().(*LoadBalanceRequest_ClientStats); ok {
+		return x.ClientStats
+	}
+	return nil
+}
+
+type isLoadBalanceRequest_LoadBalanceRequestType interface {
+	isLoadBalanceRequest_LoadBalanceRequestType()
+}
+
+type LoadBalanceRequest_InitialRequest struct {
+	// This message should be sent on the first request to the load balancer.
+	InitialRequest *InitialLoadBalanceRequest `protobuf:"bytes,1,opt,name=initial_request,json=initialRequest,proto3,oneof"`
+}
+
+type LoadBalanceRequest_ClientStats struct {
+	// The client stats should be periodically reported to the load balancer
+	// based on the duration defined in the InitialLoadBalanceResponse.
+	ClientStats *ClientStats `protobuf:"bytes,2,opt,name=client_stats,json=clientStats,proto3,oneof"`
+}
+
+func (*LoadBalanceRequest_InitialRequest) isLoadBalanceRequest_LoadBalanceRequestType() {}
+
+func (*LoadBalanceRequest_ClientStats) isLoadBalanceRequest_LoadBalanceRequestType() {}
+
+type InitialLoadBalanceRequest struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// The name of the load balanced service (e.g., service.googleapis.com). Its
+	// length should be less than 256 bytes.
+	// The name might include a port number. How to handle the port number is up
+	// to the balancer.
+	Name string `protobuf:"bytes,1,opt,name=name,proto3" json:"name,omitempty"`
+}
+
+func (x *InitialLoadBalanceRequest) Reset() {
+	*x = InitialLoadBalanceRequest{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[1]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *InitialLoadBalanceRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*InitialLoadBalanceRequest) ProtoMessage() {}
+
+func (x *InitialLoadBalanceRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[1]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use InitialLoadBalanceRequest.ProtoReflect.Descriptor instead.
+func (*InitialLoadBalanceRequest) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{1}
+}
+
+func (x *InitialLoadBalanceRequest) GetName() string {
+	if x != nil {
+		return x.Name
+	}
+	return ""
+}
+
+// Contains the number of calls finished for a particular load balance token.
+type ClientStatsPerToken struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// See Server.load_balance_token.
+	LoadBalanceToken string `protobuf:"bytes,1,opt,name=load_balance_token,json=loadBalanceToken,proto3" json:"load_balance_token,omitempty"`
+	// The total number of RPCs that finished associated with the token.
+	NumCalls int64 `protobuf:"varint,2,opt,name=num_calls,json=numCalls,proto3" json:"num_calls,omitempty"`
+}
+
+func (x *ClientStatsPerToken) Reset() {
+	*x = ClientStatsPerToken{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[2]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *ClientStatsPerToken) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ClientStatsPerToken) ProtoMessage() {}
+
+func (x *ClientStatsPerToken) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[2]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use ClientStatsPerToken.ProtoReflect.Descriptor instead.
+func (*ClientStatsPerToken) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{2}
+}
+
+func (x *ClientStatsPerToken) GetLoadBalanceToken() string {
+	if x != nil {
+		return x.LoadBalanceToken
+	}
+	return ""
+}
+
+func (x *ClientStatsPerToken) GetNumCalls() int64 {
+	if x != nil {
+		return x.NumCalls
+	}
+	return 0
+}
+
+// Contains client level statistics that are useful to load balancing. Each
+// count except the timestamp should be reset to zero after reporting the stats.
+type ClientStats struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// The timestamp of generating the report.
+	Timestamp *timestamppb.Timestamp `protobuf:"bytes,1,opt,name=timestamp,proto3" json:"timestamp,omitempty"`
+	// The total number of RPCs that started.
+	NumCallsStarted int64 `protobuf:"varint,2,opt,name=num_calls_started,json=numCallsStarted,proto3" json:"num_calls_started,omitempty"`
+	// The total number of RPCs that finished.
+	NumCallsFinished int64 `protobuf:"varint,3,opt,name=num_calls_finished,json=numCallsFinished,proto3" json:"num_calls_finished,omitempty"`
+	// The total number of RPCs that failed to reach a server except dropped RPCs.
+	NumCallsFinishedWithClientFailedToSend int64 `protobuf:"varint,6,opt,name=num_calls_finished_with_client_failed_to_send,json=numCallsFinishedWithClientFailedToSend,proto3" json:"num_calls_finished_with_client_failed_to_send,omitempty"`
+	// The total number of RPCs that finished and are known to have been received
+	// by a server.
+	NumCallsFinishedKnownReceived int64 `protobuf:"varint,7,opt,name=num_calls_finished_known_received,json=numCallsFinishedKnownReceived,proto3" json:"num_calls_finished_known_received,omitempty"`
+	// The list of dropped calls.
+	CallsFinishedWithDrop []*ClientStatsPerToken `protobuf:"bytes,8,rep,name=calls_finished_with_drop,json=callsFinishedWithDrop,proto3" json:"calls_finished_with_drop,omitempty"`
+}
+
+func (x *ClientStats) Reset() {
+	*x = ClientStats{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[3]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *ClientStats) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ClientStats) ProtoMessage() {}
+
+func (x *ClientStats) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[3]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use ClientStats.ProtoReflect.Descriptor instead.
+func (*ClientStats) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{3}
+}
+
+func (x *ClientStats) GetTimestamp() *timestamppb.Timestamp {
+	if x != nil {
+		return x.Timestamp
+	}
+	return nil
+}
+
+func (x *ClientStats) GetNumCallsStarted() int64 {
+	if x != nil {
+		return x.NumCallsStarted
+	}
+	return 0
+}
+
+func (x *ClientStats) GetNumCallsFinished() int64 {
+	if x != nil {
+		return x.NumCallsFinished
+	}
+	return 0
+}
+
+func (x *ClientStats) GetNumCallsFinishedWithClientFailedToSend() int64 {
+	if x != nil {
+		return x.NumCallsFinishedWithClientFailedToSend
+	}
+	return 0
+}
+
+func (x *ClientStats) GetNumCallsFinishedKnownReceived() int64 {
+	if x != nil {
+		return x.NumCallsFinishedKnownReceived
+	}
+	return 0
+}
+
+func (x *ClientStats) GetCallsFinishedWithDrop() []*ClientStatsPerToken {
+	if x != nil {
+		return x.CallsFinishedWithDrop
+	}
+	return nil
+}
+
+type LoadBalanceResponse struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// Types that are assignable to LoadBalanceResponseType:
+	//	*LoadBalanceResponse_InitialResponse
+	//	*LoadBalanceResponse_ServerList
+	//	*LoadBalanceResponse_FallbackResponse
+	LoadBalanceResponseType isLoadBalanceResponse_LoadBalanceResponseType `protobuf_oneof:"load_balance_response_type"`
+}
+
+func (x *LoadBalanceResponse) Reset() {
+	*x = LoadBalanceResponse{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[4]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *LoadBalanceResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*LoadBalanceResponse) ProtoMessage() {}
+
+func (x *LoadBalanceResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[4]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use LoadBalanceResponse.ProtoReflect.Descriptor instead.
+func (*LoadBalanceResponse) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{4}
+}
+
+func (m *LoadBalanceResponse) GetLoadBalanceResponseType() isLoadBalanceResponse_LoadBalanceResponseType {
+	if m != nil {
+		return m.LoadBalanceResponseType
+	}
+	return nil
+}
+
+func (x *LoadBalanceResponse) GetInitialResponse() *InitialLoadBalanceResponse {
+	if x, ok := x.GetLoadBalanceResponseType().(*LoadBalanceResponse_InitialResponse); ok {
+		return x.InitialResponse
+	}
+	return nil
+}
+
+func (x *LoadBalanceResponse) GetServerList() *ServerList {
+	if x, ok := x.GetLoadBalanceResponseType().(*LoadBalanceResponse_ServerList); ok {
+		return x.ServerList
+	}
+	return nil
+}
+
+func (x *LoadBalanceResponse) GetFallbackResponse() *FallbackResponse {
+	if x, ok := x.GetLoadBalanceResponseType().(*LoadBalanceResponse_FallbackResponse); ok {
+		return x.FallbackResponse
+	}
+	return nil
+}
+
+type isLoadBalanceResponse_LoadBalanceResponseType interface {
+	isLoadBalanceResponse_LoadBalanceResponseType()
+}
+
+type LoadBalanceResponse_InitialResponse struct {
+	// This message should be sent on the first response to the client.
+	InitialResponse *InitialLoadBalanceResponse `protobuf:"bytes,1,opt,name=initial_response,json=initialResponse,proto3,oneof"`
+}
+
+type LoadBalanceResponse_ServerList struct {
+	// Contains the list of servers selected by the load balancer. The client
+	// should send requests to these servers in the specified order.
+	ServerList *ServerList `protobuf:"bytes,2,opt,name=server_list,json=serverList,proto3,oneof"`
+}
+
+type LoadBalanceResponse_FallbackResponse struct {
+	// If this field is set, then the client should eagerly enter fallback
+	// mode (even if there are existing, healthy connections to backends).
+	FallbackResponse *FallbackResponse `protobuf:"bytes,3,opt,name=fallback_response,json=fallbackResponse,proto3,oneof"`
+}
+
+func (*LoadBalanceResponse_InitialResponse) isLoadBalanceResponse_LoadBalanceResponseType() {}
+
+func (*LoadBalanceResponse_ServerList) isLoadBalanceResponse_LoadBalanceResponseType() {}
+
+func (*LoadBalanceResponse_FallbackResponse) isLoadBalanceResponse_LoadBalanceResponseType() {}
+
+type FallbackResponse struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+}
+
+func (x *FallbackResponse) Reset() {
+	*x = FallbackResponse{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[5]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *FallbackResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*FallbackResponse) ProtoMessage() {}
+
+func (x *FallbackResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[5]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use FallbackResponse.ProtoReflect.Descriptor instead.
+func (*FallbackResponse) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{5}
+}
+
+type InitialLoadBalanceResponse struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// This interval defines how often the client should send the client stats
+	// to the load balancer. Stats should only be reported when the duration is
+	// positive.
+	ClientStatsReportInterval *durationpb.Duration `protobuf:"bytes,2,opt,name=client_stats_report_interval,json=clientStatsReportInterval,proto3" json:"client_stats_report_interval,omitempty"`
+}
+
+func (x *InitialLoadBalanceResponse) Reset() {
+	*x = InitialLoadBalanceResponse{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[6]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *InitialLoadBalanceResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*InitialLoadBalanceResponse) ProtoMessage() {}
+
+func (x *InitialLoadBalanceResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[6]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use InitialLoadBalanceResponse.ProtoReflect.Descriptor instead.
+func (*InitialLoadBalanceResponse) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{6}
+}
+
+func (x *InitialLoadBalanceResponse) GetClientStatsReportInterval() *durationpb.Duration {
+	if x != nil {
+		return x.ClientStatsReportInterval
+	}
+	return nil
+}
+
+type ServerList struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// Contains a list of servers selected by the load balancer. The list will
+	// be updated when server resolutions change or as needed to balance load
+	// across more servers. The client should consume the server list in order
+	// unless instructed otherwise via the client_config.
+	Servers []*Server `protobuf:"bytes,1,rep,name=servers,proto3" json:"servers,omitempty"`
+}
+
+func (x *ServerList) Reset() {
+	*x = ServerList{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[7]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *ServerList) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ServerList) ProtoMessage() {}
+
+func (x *ServerList) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[7]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use ServerList.ProtoReflect.Descriptor instead.
+func (*ServerList) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{7}
+}
+
+func (x *ServerList) GetServers() []*Server {
+	if x != nil {
+		return x.Servers
+	}
+	return nil
+}
+
+// Contains server information. When the drop field is not true, use the other
+// fields.
+type Server struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// A resolved address for the server, serialized in network-byte-order. It may
+	// either be an IPv4 or IPv6 address.
+	IpAddress []byte `protobuf:"bytes,1,opt,name=ip_address,json=ipAddress,proto3" json:"ip_address,omitempty"`
+	// A resolved port number for the server.
+	Port int32 `protobuf:"varint,2,opt,name=port,proto3" json:"port,omitempty"`
+	// An opaque but printable token for load reporting. The client must include
+	// the token of the picked server into the initial metadata when it starts a
+	// call to that server. The token is used by the server to verify the request
+	// and to allow the server to report load to the gRPC LB system. The token is
+	// also used in client stats for reporting dropped calls.
+	//
+	// Its length can be variable but must be less than 50 bytes.
+	LoadBalanceToken string `protobuf:"bytes,3,opt,name=load_balance_token,json=loadBalanceToken,proto3" json:"load_balance_token,omitempty"`
+	// Indicates whether this particular request should be dropped by the client.
+	// If the request is dropped, there will be a corresponding entry in
+	// ClientStats.calls_finished_with_drop.
+	Drop bool `protobuf:"varint,4,opt,name=drop,proto3" json:"drop,omitempty"`
+}
+
+func (x *Server) Reset() {
+	*x = Server{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[8]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *Server) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Server) ProtoMessage() {}
+
+func (x *Server) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_lb_v1_load_balancer_proto_msgTypes[8]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use Server.ProtoReflect.Descriptor instead.
+func (*Server) Descriptor() ([]byte, []int) {
+	return file_grpc_lb_v1_load_balancer_proto_rawDescGZIP(), []int{8}
+}
+
+func (x *Server) GetIpAddress() []byte {
+	if x != nil {
+		return x.IpAddress
+	}
+	return nil
+}
+
+func (x *Server) GetPort() int32 {
+	if x != nil {
+		return x.Port
+	}
+	return 0
+}
+
+func (x *Server) GetLoadBalanceToken() string {
+	if x != nil {
+		return x.LoadBalanceToken
+	}
+	return ""
+}
+
+func (x *Server) GetDrop() bool {
+	if x != nil {
+		return x.Drop
+	}
+	return false
+}
+
+var File_grpc_lb_v1_load_balancer_proto protoreflect.FileDescriptor
+
+var file_grpc_lb_v1_load_balancer_proto_rawDesc = []byte{
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+	0x6f, 0x6b, 0x65, 0x6e, 0x18, 0x03, 0x20, 0x01, 0x28, 0x09, 0x52, 0x10, 0x6c, 0x6f, 0x61, 0x64,
+	0x42, 0x61, 0x6c, 0x61, 0x6e, 0x63, 0x65, 0x54, 0x6f, 0x6b, 0x65, 0x6e, 0x12, 0x12, 0x0a, 0x04,
+	0x64, 0x72, 0x6f, 0x70, 0x18, 0x04, 0x20, 0x01, 0x28, 0x08, 0x52, 0x04, 0x64, 0x72, 0x6f, 0x70,
+	0x4a, 0x04, 0x08, 0x05, 0x10, 0x06, 0x32, 0x62, 0x0a, 0x0c, 0x4c, 0x6f, 0x61, 0x64, 0x42, 0x61,
+	0x6c, 0x61, 0x6e, 0x63, 0x65, 0x72, 0x12, 0x52, 0x0a, 0x0b, 0x42, 0x61, 0x6c, 0x61, 0x6e, 0x63,
+	0x65, 0x4c, 0x6f, 0x61, 0x64, 0x12, 0x1e, 0x2e, 0x67, 0x72, 0x70, 0x63, 0x2e, 0x6c, 0x62, 0x2e,
+	0x76, 0x31, 0x2e, 0x4c, 0x6f, 0x61, 0x64, 0x42, 0x61, 0x6c, 0x61, 0x6e, 0x63, 0x65, 0x52, 0x65,
+	0x71, 0x75, 0x65, 0x73, 0x74, 0x1a, 0x1f, 0x2e, 0x67, 0x72, 0x70, 0x63, 0x2e, 0x6c, 0x62, 0x2e,
+	0x76, 0x31, 0x2e, 0x4c, 0x6f, 0x61, 0x64, 0x42, 0x61, 0x6c, 0x61, 0x6e, 0x63, 0x65, 0x52, 0x65,
+	0x73, 0x70, 0x6f, 0x6e, 0x73, 0x65, 0x28, 0x01, 0x30, 0x01, 0x42, 0x57, 0x0a, 0x0d, 0x69, 0x6f,
+	0x2e, 0x67, 0x72, 0x70, 0x63, 0x2e, 0x6c, 0x62, 0x2e, 0x76, 0x31, 0x42, 0x11, 0x4c, 0x6f, 0x61,
+	0x64, 0x42, 0x61, 0x6c, 0x61, 0x6e, 0x63, 0x65, 0x72, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01,
+	0x5a, 0x31, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61, 0x6e, 0x67, 0x2e,
+	0x6f, 0x72, 0x67, 0x2f, 0x67, 0x72, 0x70, 0x63, 0x2f, 0x62, 0x61, 0x6c, 0x61, 0x6e, 0x63, 0x65,
+	0x72, 0x2f, 0x67, 0x72, 0x70, 0x63, 0x6c, 0x62, 0x2f, 0x67, 0x72, 0x70, 0x63, 0x5f, 0x6c, 0x62,
+	0x5f, 0x76, 0x31, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_grpc_lb_v1_load_balancer_proto_rawDescOnce sync.Once
+	file_grpc_lb_v1_load_balancer_proto_rawDescData = file_grpc_lb_v1_load_balancer_proto_rawDesc
+)
+
+func file_grpc_lb_v1_load_balancer_proto_rawDescGZIP() []byte {
+	file_grpc_lb_v1_load_balancer_proto_rawDescOnce.Do(func() {
+		file_grpc_lb_v1_load_balancer_proto_rawDescData = protoimpl.X.CompressGZIP(file_grpc_lb_v1_load_balancer_proto_rawDescData)
+	})
+	return file_grpc_lb_v1_load_balancer_proto_rawDescData
+}
+
+var file_grpc_lb_v1_load_balancer_proto_msgTypes = make([]protoimpl.MessageInfo, 9)
+var file_grpc_lb_v1_load_balancer_proto_goTypes = []interface{}{
+	(*LoadBalanceRequest)(nil),         // 0: grpc.lb.v1.LoadBalanceRequest
+	(*InitialLoadBalanceRequest)(nil),  // 1: grpc.lb.v1.InitialLoadBalanceRequest
+	(*ClientStatsPerToken)(nil),        // 2: grpc.lb.v1.ClientStatsPerToken
+	(*ClientStats)(nil),                // 3: grpc.lb.v1.ClientStats
+	(*LoadBalanceResponse)(nil),        // 4: grpc.lb.v1.LoadBalanceResponse
+	(*FallbackResponse)(nil),           // 5: grpc.lb.v1.FallbackResponse
+	(*InitialLoadBalanceResponse)(nil), // 6: grpc.lb.v1.InitialLoadBalanceResponse
+	(*ServerList)(nil),                 // 7: grpc.lb.v1.ServerList
+	(*Server)(nil),                     // 8: grpc.lb.v1.Server
+	(*timestamppb.Timestamp)(nil),      // 9: google.protobuf.Timestamp
+	(*durationpb.Duration)(nil),        // 10: google.protobuf.Duration
+}
+var file_grpc_lb_v1_load_balancer_proto_depIdxs = []int32{
+	1,  // 0: grpc.lb.v1.LoadBalanceRequest.initial_request:type_name -> grpc.lb.v1.InitialLoadBalanceRequest
+	3,  // 1: grpc.lb.v1.LoadBalanceRequest.client_stats:type_name -> grpc.lb.v1.ClientStats
+	9,  // 2: grpc.lb.v1.ClientStats.timestamp:type_name -> google.protobuf.Timestamp
+	2,  // 3: grpc.lb.v1.ClientStats.calls_finished_with_drop:type_name -> grpc.lb.v1.ClientStatsPerToken
+	6,  // 4: grpc.lb.v1.LoadBalanceResponse.initial_response:type_name -> grpc.lb.v1.InitialLoadBalanceResponse
+	7,  // 5: grpc.lb.v1.LoadBalanceResponse.server_list:type_name -> grpc.lb.v1.ServerList
+	5,  // 6: grpc.lb.v1.LoadBalanceResponse.fallback_response:type_name -> grpc.lb.v1.FallbackResponse
+	10, // 7: grpc.lb.v1.InitialLoadBalanceResponse.client_stats_report_interval:type_name -> google.protobuf.Duration
+	8,  // 8: grpc.lb.v1.ServerList.servers:type_name -> grpc.lb.v1.Server
+	0,  // 9: grpc.lb.v1.LoadBalancer.BalanceLoad:input_type -> grpc.lb.v1.LoadBalanceRequest
+	4,  // 10: grpc.lb.v1.LoadBalancer.BalanceLoad:output_type -> grpc.lb.v1.LoadBalanceResponse
+	10, // [10:11] is the sub-list for method output_type
+	9,  // [9:10] is the sub-list for method input_type
+	9,  // [9:9] is the sub-list for extension type_name
+	9,  // [9:9] is the sub-list for extension extendee
+	0,  // [0:9] is the sub-list for field type_name
+}
+
+func init() { file_grpc_lb_v1_load_balancer_proto_init() }
+func file_grpc_lb_v1_load_balancer_proto_init() {
+	if File_grpc_lb_v1_load_balancer_proto != nil {
+		return
+	}
+	if !protoimpl.UnsafeEnabled {
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*LoadBalanceRequest); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[1].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*InitialLoadBalanceRequest); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[2].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*ClientStatsPerToken); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[3].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*ClientStats); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[4].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*LoadBalanceResponse); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[5].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*FallbackResponse); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[6].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*InitialLoadBalanceResponse); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[7].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*ServerList); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_lb_v1_load_balancer_proto_msgTypes[8].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*Server); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	file_grpc_lb_v1_load_balancer_proto_msgTypes[0].OneofWrappers = []interface{}{
+		(*LoadBalanceRequest_InitialRequest)(nil),
+		(*LoadBalanceRequest_ClientStats)(nil),
+	}
+	file_grpc_lb_v1_load_balancer_proto_msgTypes[4].OneofWrappers = []interface{}{
+		(*LoadBalanceResponse_InitialResponse)(nil),
+		(*LoadBalanceResponse_ServerList)(nil),
+		(*LoadBalanceResponse_FallbackResponse)(nil),
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_grpc_lb_v1_load_balancer_proto_rawDesc,
+			NumEnums:      0,
+			NumMessages:   9,
+			NumExtensions: 0,
+			NumServices:   1,
+		},
+		GoTypes:           file_grpc_lb_v1_load_balancer_proto_goTypes,
+		DependencyIndexes: file_grpc_lb_v1_load_balancer_proto_depIdxs,
+		MessageInfos:      file_grpc_lb_v1_load_balancer_proto_msgTypes,
+	}.Build()
+	File_grpc_lb_v1_load_balancer_proto = out.File
+	file_grpc_lb_v1_load_balancer_proto_rawDesc = nil
+	file_grpc_lb_v1_load_balancer_proto_goTypes = nil
+	file_grpc_lb_v1_load_balancer_proto_depIdxs = nil
+}

vendor/google.golang.org/grpc/balancer/grpclb/grpc_lb_v1/load_balancer_grpc.pb.go

@@ -0,0 +1,137 @@
+// Code generated by protoc-gen-go-grpc. DO NOT EDIT.
+// versions:
+// - protoc-gen-go-grpc v1.1.0
+// - protoc             v3.14.0
+// source: grpc/lb/v1/load_balancer.proto
+
+package grpc_lb_v1
+
+import (
+	context "context"
+	grpc "google.golang.org/grpc"
+	codes "google.golang.org/grpc/codes"
+	status "google.golang.org/grpc/status"
+)
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+// Requires gRPC-Go v1.32.0 or later.
+const _ = grpc.SupportPackageIsVersion7
+
+// LoadBalancerClient is the client API for LoadBalancer service.
+//
+// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream.
+type LoadBalancerClient interface {
+	// Bidirectional rpc to get a list of servers.
+	BalanceLoad(ctx context.Context, opts ...grpc.CallOption) (LoadBalancer_BalanceLoadClient, error)
+}
+
+type loadBalancerClient struct {
+	cc grpc.ClientConnInterface
+}
+
+func NewLoadBalancerClient(cc grpc.ClientConnInterface) LoadBalancerClient {
+	return &loadBalancerClient{cc}
+}
+
+func (c *loadBalancerClient) BalanceLoad(ctx context.Context, opts ...grpc.CallOption) (LoadBalancer_BalanceLoadClient, error) {
+	stream, err := c.cc.NewStream(ctx, &LoadBalancer_ServiceDesc.Streams[0], "/grpc.lb.v1.LoadBalancer/BalanceLoad", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &loadBalancerBalanceLoadClient{stream}
+	return x, nil
+}
+
+type LoadBalancer_BalanceLoadClient interface {
+	Send(*LoadBalanceRequest) error
+	Recv() (*LoadBalanceResponse, error)
+	grpc.ClientStream
+}
+
+type loadBalancerBalanceLoadClient struct {
+	grpc.ClientStream
+}
+
+func (x *loadBalancerBalanceLoadClient) Send(m *LoadBalanceRequest) error {
+	return x.ClientStream.SendMsg(m)
+}
+
+func (x *loadBalancerBalanceLoadClient) Recv() (*LoadBalanceResponse, error) {
+	m := new(LoadBalanceResponse)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// LoadBalancerServer is the server API for LoadBalancer service.
+// All implementations should embed UnimplementedLoadBalancerServer
+// for forward compatibility
+type LoadBalancerServer interface {
+	// Bidirectional rpc to get a list of servers.
+	BalanceLoad(LoadBalancer_BalanceLoadServer) error
+}
+
+// UnimplementedLoadBalancerServer should be embedded to have forward compatible implementations.
+type UnimplementedLoadBalancerServer struct {
+}
+
+func (UnimplementedLoadBalancerServer) BalanceLoad(LoadBalancer_BalanceLoadServer) error {
+	return status.Errorf(codes.Unimplemented, "method BalanceLoad not implemented")
+}
+
+// UnsafeLoadBalancerServer may be embedded to opt out of forward compatibility for this service.
+// Use of this interface is not recommended, as added methods to LoadBalancerServer will
+// result in compilation errors.
+type UnsafeLoadBalancerServer interface {
+	mustEmbedUnimplementedLoadBalancerServer()
+}
+
+func RegisterLoadBalancerServer(s grpc.ServiceRegistrar, srv LoadBalancerServer) {
+	s.RegisterService(&LoadBalancer_ServiceDesc, srv)
+}
+
+func _LoadBalancer_BalanceLoad_Handler(srv interface{}, stream grpc.ServerStream) error {
+	return srv.(LoadBalancerServer).BalanceLoad(&loadBalancerBalanceLoadServer{stream})
+}
+
+type LoadBalancer_BalanceLoadServer interface {
+	Send(*LoadBalanceResponse) error
+	Recv() (*LoadBalanceRequest, error)
+	grpc.ServerStream
+}
+
+type loadBalancerBalanceLoadServer struct {
+	grpc.ServerStream
+}
+
+func (x *loadBalancerBalanceLoadServer) Send(m *LoadBalanceResponse) error {
+	return x.ServerStream.SendMsg(m)
+}
+
+func (x *loadBalancerBalanceLoadServer) Recv() (*LoadBalanceRequest, error) {
+	m := new(LoadBalanceRequest)
+	if err := x.ServerStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// LoadBalancer_ServiceDesc is the grpc.ServiceDesc for LoadBalancer service.
+// It's only intended for direct use with grpc.RegisterService,
+// and not to be introspected or modified (even as a copy)
+var LoadBalancer_ServiceDesc = grpc.ServiceDesc{
+	ServiceName: "grpc.lb.v1.LoadBalancer",
+	HandlerType: (*LoadBalancerServer)(nil),
+	Methods:     []grpc.MethodDesc{},
+	Streams: []grpc.StreamDesc{
+		{
+			StreamName:    "BalanceLoad",
+			Handler:       _LoadBalancer_BalanceLoad_Handler,
+			ServerStreams: true,
+			ClientStreams: true,
+		},
+	},
+	Metadata: "grpc/lb/v1/load_balancer.proto",
+}

vendor/google.golang.org/grpc/balancer/grpclb/grpclb.go

@@ -0,0 +1,490 @@
+/*
+ *
+ * Copyright 2016 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package grpclb defines a grpclb balancer.
+//
+// To install grpclb balancer, import this package as:
+//    import _ "google.golang.org/grpc/balancer/grpclb"
+package grpclb
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/balancer"
+	grpclbstate "google.golang.org/grpc/balancer/grpclb/state"
+	"google.golang.org/grpc/connectivity"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal"
+	"google.golang.org/grpc/internal/backoff"
+	"google.golang.org/grpc/internal/resolver/dns"
+	"google.golang.org/grpc/resolver"
+
+	durationpb "github.com/golang/protobuf/ptypes/duration"
+	lbpb "google.golang.org/grpc/balancer/grpclb/grpc_lb_v1"
+)
+
+const (
+	lbTokenKey             = "lb-token"
+	defaultFallbackTimeout = 10 * time.Second
+	grpclbName             = "grpclb"
+)
+
+var errServerTerminatedConnection = errors.New("grpclb: failed to recv server list: server terminated connection")
+var logger = grpclog.Component("grpclb")
+
+func convertDuration(d *durationpb.Duration) time.Duration {
+	if d == nil {
+		return 0
+	}
+	return time.Duration(d.Seconds)*time.Second + time.Duration(d.Nanos)*time.Nanosecond
+}
+
+// Client API for LoadBalancer service.
+// Mostly copied from generated pb.go file.
+// To avoid circular dependency.
+type loadBalancerClient struct {
+	cc *grpc.ClientConn
+}
+
+func (c *loadBalancerClient) BalanceLoad(ctx context.Context, opts ...grpc.CallOption) (*balanceLoadClientStream, error) {
+	desc := &grpc.StreamDesc{
+		StreamName:    "BalanceLoad",
+		ServerStreams: true,
+		ClientStreams: true,
+	}
+	stream, err := c.cc.NewStream(ctx, desc, "/grpc.lb.v1.LoadBalancer/BalanceLoad", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &balanceLoadClientStream{stream}
+	return x, nil
+}
+
+type balanceLoadClientStream struct {
+	grpc.ClientStream
+}
+
+func (x *balanceLoadClientStream) Send(m *lbpb.LoadBalanceRequest) error {
+	return x.ClientStream.SendMsg(m)
+}
+
+func (x *balanceLoadClientStream) Recv() (*lbpb.LoadBalanceResponse, error) {
+	m := new(lbpb.LoadBalanceResponse)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+func init() {
+	balancer.Register(newLBBuilder())
+	dns.EnableSRVLookups = true
+}
+
+// newLBBuilder creates a builder for grpclb.
+func newLBBuilder() balancer.Builder {
+	return newLBBuilderWithFallbackTimeout(defaultFallbackTimeout)
+}
+
+// newLBBuilderWithFallbackTimeout creates a grpclb builder with the given
+// fallbackTimeout. If no response is received from the remote balancer within
+// fallbackTimeout, the backend addresses from the resolved address list will be
+// used.
+//
+// Only call this function when a non-default fallback timeout is needed.
+func newLBBuilderWithFallbackTimeout(fallbackTimeout time.Duration) balancer.Builder {
+	return &lbBuilder{
+		fallbackTimeout: fallbackTimeout,
+	}
+}
+
+type lbBuilder struct {
+	fallbackTimeout time.Duration
+}
+
+func (b *lbBuilder) Name() string {
+	return grpclbName
+}
+
+func (b *lbBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer {
+	// This generates a manual resolver builder with a fixed scheme. This
+	// scheme will be used to dial to remote LB, so we can send filtered
+	// address updates to remote LB ClientConn using this manual resolver.
+	r := &lbManualResolver{scheme: "grpclb-internal", ccb: cc}
+
+	lb := &lbBalancer{
+		cc:              newLBCacheClientConn(cc),
+		target:          opt.Target.Endpoint,
+		opt:             opt,
+		fallbackTimeout: b.fallbackTimeout,
+		doneCh:          make(chan struct{}),
+
+		manualResolver: r,
+		subConns:       make(map[resolver.Address]balancer.SubConn),
+		scStates:       make(map[balancer.SubConn]connectivity.State),
+		picker:         &errPicker{err: balancer.ErrNoSubConnAvailable},
+		clientStats:    newRPCStats(),
+		backoff:        backoff.DefaultExponential, // TODO: make backoff configurable.
+	}
+
+	var err error
+	if opt.CredsBundle != nil {
+		lb.grpclbClientConnCreds, err = opt.CredsBundle.NewWithMode(internal.CredsBundleModeBalancer)
+		if err != nil {
+			logger.Warningf("lbBalancer: client connection creds NewWithMode failed: %v", err)
+		}
+		lb.grpclbBackendCreds, err = opt.CredsBundle.NewWithMode(internal.CredsBundleModeBackendFromBalancer)
+		if err != nil {
+			logger.Warningf("lbBalancer: backend creds NewWithMode failed: %v", err)
+		}
+	}
+
+	return lb
+}
+
+type lbBalancer struct {
+	cc     *lbCacheClientConn
+	target string
+	opt    balancer.BuildOptions
+
+	usePickFirst bool
+
+	// grpclbClientConnCreds is the creds bundle to be used to connect to grpclb
+	// servers. If it's nil, use the TransportCredentials from BuildOptions
+	// instead.
+	grpclbClientConnCreds credentials.Bundle
+	// grpclbBackendCreds is the creds bundle to be used for addresses that are
+	// returned by grpclb server. If it's nil, don't set anything when creating
+	// SubConns.
+	grpclbBackendCreds credentials.Bundle
+
+	fallbackTimeout time.Duration
+	doneCh          chan struct{}
+
+	// manualResolver is used in the remote LB ClientConn inside grpclb. When
+	// resolved address updates are received by grpclb, filtered updates will be
+	// send to remote LB ClientConn through this resolver.
+	manualResolver *lbManualResolver
+	// The ClientConn to talk to the remote balancer.
+	ccRemoteLB *remoteBalancerCCWrapper
+	// backoff for calling remote balancer.
+	backoff backoff.Strategy
+
+	// Support client side load reporting. Each picker gets a reference to this,
+	// and will update its content.
+	clientStats *rpcStats
+
+	mu sync.Mutex // guards everything following.
+	// The full server list including drops, used to check if the newly received
+	// serverList contains anything new. Each generate picker will also have
+	// reference to this list to do the first layer pick.
+	fullServerList []*lbpb.Server
+	// Backend addresses. It's kept so the addresses are available when
+	// switching between round_robin and pickfirst.
+	backendAddrs []resolver.Address
+	// All backends addresses, with metadata set to nil. This list contains all
+	// backend addresses in the same order and with the same duplicates as in
+	// serverlist. When generating picker, a SubConn slice with the same order
+	// but with only READY SCs will be gerenated.
+	backendAddrsWithoutMetadata []resolver.Address
+	// Roundrobin functionalities.
+	state    connectivity.State
+	subConns map[resolver.Address]balancer.SubConn   // Used to new/remove SubConn.
+	scStates map[balancer.SubConn]connectivity.State // Used to filter READY SubConns.
+	picker   balancer.Picker
+	// Support fallback to resolved backend addresses if there's no response
+	// from remote balancer within fallbackTimeout.
+	remoteBalancerConnected bool
+	serverListReceived      bool
+	inFallback              bool
+	// resolvedBackendAddrs is resolvedAddrs minus remote balancers. It's set
+	// when resolved address updates are received, and read in the goroutine
+	// handling fallback.
+	resolvedBackendAddrs []resolver.Address
+	connErr              error // the last connection error
+}
+
+// regeneratePicker takes a snapshot of the balancer, and generates a picker from
+// it. The picker
+//  - always returns ErrTransientFailure if the balancer is in TransientFailure,
+//  - does two layer roundrobin pick otherwise.
+// Caller must hold lb.mu.
+func (lb *lbBalancer) regeneratePicker(resetDrop bool) {
+	if lb.state == connectivity.TransientFailure {
+		lb.picker = &errPicker{err: fmt.Errorf("all SubConns are in TransientFailure, last connection error: %v", lb.connErr)}
+		return
+	}
+
+	if lb.state == connectivity.Connecting {
+		lb.picker = &errPicker{err: balancer.ErrNoSubConnAvailable}
+		return
+	}
+
+	var readySCs []balancer.SubConn
+	if lb.usePickFirst {
+		for _, sc := range lb.subConns {
+			readySCs = append(readySCs, sc)
+			break
+		}
+	} else {
+		for _, a := range lb.backendAddrsWithoutMetadata {
+			if sc, ok := lb.subConns[a]; ok {
+				if st, ok := lb.scStates[sc]; ok && st == connectivity.Ready {
+					readySCs = append(readySCs, sc)
+				}
+			}
+		}
+	}
+
+	if len(readySCs) <= 0 {
+		// If there's no ready SubConns, always re-pick. This is to avoid drops
+		// unless at least one SubConn is ready. Otherwise we may drop more
+		// often than want because of drops + re-picks(which become re-drops).
+		//
+		// This doesn't seem to be necessary after the connecting check above.
+		// Kept for safety.
+		lb.picker = &errPicker{err: balancer.ErrNoSubConnAvailable}
+		return
+	}
+	if lb.inFallback {
+		lb.picker = newRRPicker(readySCs)
+		return
+	}
+	if resetDrop {
+		lb.picker = newLBPicker(lb.fullServerList, readySCs, lb.clientStats)
+		return
+	}
+	prevLBPicker, ok := lb.picker.(*lbPicker)
+	if !ok {
+		lb.picker = newLBPicker(lb.fullServerList, readySCs, lb.clientStats)
+		return
+	}
+	prevLBPicker.updateReadySCs(readySCs)
+}
+
+// aggregateSubConnStats calculate the aggregated state of SubConns in
+// lb.SubConns. These SubConns are subconns in use (when switching between
+// fallback and grpclb). lb.scState contains states for all SubConns, including
+// those in cache (SubConns are cached for 10 seconds after remove).
+//
+// The aggregated state is:
+//  - If at least one SubConn in Ready, the aggregated state is Ready;
+//  - Else if at least one SubConn in Connecting or IDLE, the aggregated state is Connecting;
+//    - It's OK to consider IDLE as Connecting. SubConns never stay in IDLE,
+//    they start to connect immediately. But there's a race between the overall
+//    state is reported, and when the new SubConn state arrives. And SubConns
+//    never go back to IDLE.
+//  - Else the aggregated state is TransientFailure.
+func (lb *lbBalancer) aggregateSubConnStates() connectivity.State {
+	var numConnecting uint64
+
+	for _, sc := range lb.subConns {
+		if state, ok := lb.scStates[sc]; ok {
+			switch state {
+			case connectivity.Ready:
+				return connectivity.Ready
+			case connectivity.Connecting, connectivity.Idle:
+				numConnecting++
+			}
+		}
+	}
+	if numConnecting > 0 {
+		return connectivity.Connecting
+	}
+	return connectivity.TransientFailure
+}
+
+func (lb *lbBalancer) UpdateSubConnState(sc balancer.SubConn, scs balancer.SubConnState) {
+	s := scs.ConnectivityState
+	if logger.V(2) {
+		logger.Infof("lbBalancer: handle SubConn state change: %p, %v", sc, s)
+	}
+	lb.mu.Lock()
+	defer lb.mu.Unlock()
+
+	oldS, ok := lb.scStates[sc]
+	if !ok {
+		if logger.V(2) {
+			logger.Infof("lbBalancer: got state changes for an unknown SubConn: %p, %v", sc, s)
+		}
+		return
+	}
+	lb.scStates[sc] = s
+	switch s {
+	case connectivity.Idle:
+		sc.Connect()
+	case connectivity.Shutdown:
+		// When an address was removed by resolver, b called RemoveSubConn but
+		// kept the sc's state in scStates. Remove state for this sc here.
+		delete(lb.scStates, sc)
+	case connectivity.TransientFailure:
+		lb.connErr = scs.ConnectionError
+	}
+	// Force regenerate picker if
+	//  - this sc became ready from not-ready
+	//  - this sc became not-ready from ready
+	lb.updateStateAndPicker((oldS == connectivity.Ready) != (s == connectivity.Ready), false)
+
+	// Enter fallback when the aggregated state is not Ready and the connection
+	// to remote balancer is lost.
+	if lb.state != connectivity.Ready {
+		if !lb.inFallback && !lb.remoteBalancerConnected {
+			// Enter fallback.
+			lb.refreshSubConns(lb.resolvedBackendAddrs, true, lb.usePickFirst)
+		}
+	}
+}
+
+// updateStateAndPicker re-calculate the aggregated state, and regenerate picker
+// if overall state is changed.
+//
+// If forceRegeneratePicker is true, picker will be regenerated.
+func (lb *lbBalancer) updateStateAndPicker(forceRegeneratePicker bool, resetDrop bool) {
+	oldAggrState := lb.state
+	lb.state = lb.aggregateSubConnStates()
+	// Regenerate picker when one of the following happens:
+	//  - caller wants to regenerate
+	//  - the aggregated state changed
+	if forceRegeneratePicker || (lb.state != oldAggrState) {
+		lb.regeneratePicker(resetDrop)
+	}
+
+	lb.cc.UpdateState(balancer.State{ConnectivityState: lb.state, Picker: lb.picker})
+}
+
+// fallbackToBackendsAfter blocks for fallbackTimeout and falls back to use
+// resolved backends (backends received from resolver, not from remote balancer)
+// if no connection to remote balancers was successful.
+func (lb *lbBalancer) fallbackToBackendsAfter(fallbackTimeout time.Duration) {
+	timer := time.NewTimer(fallbackTimeout)
+	defer timer.Stop()
+	select {
+	case <-timer.C:
+	case <-lb.doneCh:
+		return
+	}
+	lb.mu.Lock()
+	if lb.inFallback || lb.serverListReceived {
+		lb.mu.Unlock()
+		return
+	}
+	// Enter fallback.
+	lb.refreshSubConns(lb.resolvedBackendAddrs, true, lb.usePickFirst)
+	lb.mu.Unlock()
+}
+
+func (lb *lbBalancer) handleServiceConfig(gc *grpclbServiceConfig) {
+	lb.mu.Lock()
+	defer lb.mu.Unlock()
+
+	newUsePickFirst := childIsPickFirst(gc)
+	if lb.usePickFirst == newUsePickFirst {
+		return
+	}
+	if logger.V(2) {
+		logger.Infof("lbBalancer: switching mode, new usePickFirst: %+v", newUsePickFirst)
+	}
+	lb.refreshSubConns(lb.backendAddrs, lb.inFallback, newUsePickFirst)
+}
+
+func (lb *lbBalancer) ResolverError(error) {
+	// Ignore resolver errors.  GRPCLB is not selected unless the resolver
+	// works at least once.
+}
+
+func (lb *lbBalancer) UpdateClientConnState(ccs balancer.ClientConnState) error {
+	if logger.V(2) {
+		logger.Infof("lbBalancer: UpdateClientConnState: %+v", ccs)
+	}
+	gc, _ := ccs.BalancerConfig.(*grpclbServiceConfig)
+	lb.handleServiceConfig(gc)
+
+	addrs := ccs.ResolverState.Addresses
+
+	var remoteBalancerAddrs, backendAddrs []resolver.Address
+	for _, a := range addrs {
+		if a.Type == resolver.GRPCLB {
+			a.Type = resolver.Backend
+			remoteBalancerAddrs = append(remoteBalancerAddrs, a)
+		} else {
+			backendAddrs = append(backendAddrs, a)
+		}
+	}
+	if sd := grpclbstate.Get(ccs.ResolverState); sd != nil {
+		// Override any balancer addresses provided via
+		// ccs.ResolverState.Addresses.
+		remoteBalancerAddrs = sd.BalancerAddresses
+	}
+
+	if len(backendAddrs)+len(remoteBalancerAddrs) == 0 {
+		// There should be at least one address, either grpclb server or
+		// fallback. Empty address is not valid.
+		return balancer.ErrBadResolverState
+	}
+
+	if len(remoteBalancerAddrs) == 0 {
+		if lb.ccRemoteLB != nil {
+			lb.ccRemoteLB.close()
+			lb.ccRemoteLB = nil
+		}
+	} else if lb.ccRemoteLB == nil {
+		// First time receiving resolved addresses, create a cc to remote
+		// balancers.
+		lb.newRemoteBalancerCCWrapper()
+		// Start the fallback goroutine.
+		go lb.fallbackToBackendsAfter(lb.fallbackTimeout)
+	}
+
+	if lb.ccRemoteLB != nil {
+		// cc to remote balancers uses lb.manualResolver. Send the updated remote
+		// balancer addresses to it through manualResolver.
+		lb.manualResolver.UpdateState(resolver.State{Addresses: remoteBalancerAddrs})
+	}
+
+	lb.mu.Lock()
+	lb.resolvedBackendAddrs = backendAddrs
+	if len(remoteBalancerAddrs) == 0 || lb.inFallback {
+		// If there's no remote balancer address in ClientConn update, grpclb
+		// enters fallback mode immediately.
+		//
+		// If a new update is received while grpclb is in fallback, update the
+		// list of backends being used to the new fallback backends.
+		lb.refreshSubConns(lb.resolvedBackendAddrs, true, lb.usePickFirst)
+	}
+	lb.mu.Unlock()
+	return nil
+}
+
+func (lb *lbBalancer) Close() {
+	select {
+	case <-lb.doneCh:
+		return
+	default:
+	}
+	close(lb.doneCh)
+	if lb.ccRemoteLB != nil {
+		lb.ccRemoteLB.close()
+	}
+	lb.cc.close()
+}

vendor/google.golang.org/grpc/balancer/grpclb/grpclb_config.go

@@ -0,0 +1,66 @@
+/*
+ *
+ * Copyright 2019 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpclb
+
+import (
+	"encoding/json"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/balancer/roundrobin"
+	"google.golang.org/grpc/serviceconfig"
+)
+
+const (
+	roundRobinName = roundrobin.Name
+	pickFirstName  = grpc.PickFirstBalancerName
+)
+
+type grpclbServiceConfig struct {
+	serviceconfig.LoadBalancingConfig
+	ChildPolicy *[]map[string]json.RawMessage
+}
+
+func (b *lbBuilder) ParseConfig(lbConfig json.RawMessage) (serviceconfig.LoadBalancingConfig, error) {
+	ret := &grpclbServiceConfig{}
+	if err := json.Unmarshal(lbConfig, ret); err != nil {
+		return nil, err
+	}
+	return ret, nil
+}
+
+func childIsPickFirst(sc *grpclbServiceConfig) bool {
+	if sc == nil {
+		return false
+	}
+	childConfigs := sc.ChildPolicy
+	if childConfigs == nil {
+		return false
+	}
+	for _, childC := range *childConfigs {
+		// If round_robin exists before pick_first, return false
+		if _, ok := childC[roundRobinName]; ok {
+			return false
+		}
+		// If pick_first is before round_robin, return true
+		if _, ok := childC[pickFirstName]; ok {
+			return true
+		}
+	}
+	return false
+}

vendor/google.golang.org/grpc/balancer/grpclb/grpclb_picker.go

@@ -0,0 +1,202 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpclb
+
+import (
+	"sync"
+	"sync/atomic"
+
+	"google.golang.org/grpc/balancer"
+	lbpb "google.golang.org/grpc/balancer/grpclb/grpc_lb_v1"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/internal/grpcrand"
+	"google.golang.org/grpc/status"
+)
+
+// rpcStats is same as lbpb.ClientStats, except that numCallsDropped is a map
+// instead of a slice.
+type rpcStats struct {
+	// Only access the following fields atomically.
+	numCallsStarted                        int64
+	numCallsFinished                       int64
+	numCallsFinishedWithClientFailedToSend int64
+	numCallsFinishedKnownReceived          int64
+
+	mu sync.Mutex
+	// map load_balance_token -> num_calls_dropped
+	numCallsDropped map[string]int64
+}
+
+func newRPCStats() *rpcStats {
+	return &rpcStats{
+		numCallsDropped: make(map[string]int64),
+	}
+}
+
+func isZeroStats(stats *lbpb.ClientStats) bool {
+	return len(stats.CallsFinishedWithDrop) == 0 &&
+		stats.NumCallsStarted == 0 &&
+		stats.NumCallsFinished == 0 &&
+		stats.NumCallsFinishedWithClientFailedToSend == 0 &&
+		stats.NumCallsFinishedKnownReceived == 0
+}
+
+// toClientStats converts rpcStats to lbpb.ClientStats, and clears rpcStats.
+func (s *rpcStats) toClientStats() *lbpb.ClientStats {
+	stats := &lbpb.ClientStats{
+		NumCallsStarted:                        atomic.SwapInt64(&s.numCallsStarted, 0),
+		NumCallsFinished:                       atomic.SwapInt64(&s.numCallsFinished, 0),
+		NumCallsFinishedWithClientFailedToSend: atomic.SwapInt64(&s.numCallsFinishedWithClientFailedToSend, 0),
+		NumCallsFinishedKnownReceived:          atomic.SwapInt64(&s.numCallsFinishedKnownReceived, 0),
+	}
+	s.mu.Lock()
+	dropped := s.numCallsDropped
+	s.numCallsDropped = make(map[string]int64)
+	s.mu.Unlock()
+	for token, count := range dropped {
+		stats.CallsFinishedWithDrop = append(stats.CallsFinishedWithDrop, &lbpb.ClientStatsPerToken{
+			LoadBalanceToken: token,
+			NumCalls:         count,
+		})
+	}
+	return stats
+}
+
+func (s *rpcStats) drop(token string) {
+	atomic.AddInt64(&s.numCallsStarted, 1)
+	s.mu.Lock()
+	s.numCallsDropped[token]++
+	s.mu.Unlock()
+	atomic.AddInt64(&s.numCallsFinished, 1)
+}
+
+func (s *rpcStats) failedToSend() {
+	atomic.AddInt64(&s.numCallsStarted, 1)
+	atomic.AddInt64(&s.numCallsFinishedWithClientFailedToSend, 1)
+	atomic.AddInt64(&s.numCallsFinished, 1)
+}
+
+func (s *rpcStats) knownReceived() {
+	atomic.AddInt64(&s.numCallsStarted, 1)
+	atomic.AddInt64(&s.numCallsFinishedKnownReceived, 1)
+	atomic.AddInt64(&s.numCallsFinished, 1)
+}
+
+type errPicker struct {
+	// Pick always returns this err.
+	err error
+}
+
+func (p *errPicker) Pick(balancer.PickInfo) (balancer.PickResult, error) {
+	return balancer.PickResult{}, p.err
+}
+
+// rrPicker does roundrobin on subConns. It's typically used when there's no
+// response from remote balancer, and grpclb falls back to the resolved
+// backends.
+//
+// It guaranteed that len(subConns) > 0.
+type rrPicker struct {
+	mu           sync.Mutex
+	subConns     []balancer.SubConn // The subConns that were READY when taking the snapshot.
+	subConnsNext int
+}
+
+func newRRPicker(readySCs []balancer.SubConn) *rrPicker {
+	return &rrPicker{
+		subConns:     readySCs,
+		subConnsNext: grpcrand.Intn(len(readySCs)),
+	}
+}
+
+func (p *rrPicker) Pick(balancer.PickInfo) (balancer.PickResult, error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	sc := p.subConns[p.subConnsNext]
+	p.subConnsNext = (p.subConnsNext + 1) % len(p.subConns)
+	return balancer.PickResult{SubConn: sc}, nil
+}
+
+// lbPicker does two layers of picks:
+//
+// First layer: roundrobin on all servers in serverList, including drops and backends.
+// - If it picks a drop, the RPC will fail as being dropped.
+// - If it picks a backend, do a second layer pick to pick the real backend.
+//
+// Second layer: roundrobin on all READY backends.
+//
+// It's guaranteed that len(serverList) > 0.
+type lbPicker struct {
+	mu             sync.Mutex
+	serverList     []*lbpb.Server
+	serverListNext int
+	subConns       []balancer.SubConn // The subConns that were READY when taking the snapshot.
+	subConnsNext   int
+
+	stats *rpcStats
+}
+
+func newLBPicker(serverList []*lbpb.Server, readySCs []balancer.SubConn, stats *rpcStats) *lbPicker {
+	return &lbPicker{
+		serverList:   serverList,
+		subConns:     readySCs,
+		subConnsNext: grpcrand.Intn(len(readySCs)),
+		stats:        stats,
+	}
+}
+
+func (p *lbPicker) Pick(balancer.PickInfo) (balancer.PickResult, error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	// Layer one roundrobin on serverList.
+	s := p.serverList[p.serverListNext]
+	p.serverListNext = (p.serverListNext + 1) % len(p.serverList)
+
+	// If it's a drop, return an error and fail the RPC.
+	if s.Drop {
+		p.stats.drop(s.LoadBalanceToken)
+		return balancer.PickResult{}, status.Errorf(codes.Unavailable, "request dropped by grpclb")
+	}
+
+	// If not a drop but there's no ready subConns.
+	if len(p.subConns) <= 0 {
+		return balancer.PickResult{}, balancer.ErrNoSubConnAvailable
+	}
+
+	// Return the next ready subConn in the list, also collect rpc stats.
+	sc := p.subConns[p.subConnsNext]
+	p.subConnsNext = (p.subConnsNext + 1) % len(p.subConns)
+	done := func(info balancer.DoneInfo) {
+		if !info.BytesSent {
+			p.stats.failedToSend()
+		} else if info.BytesReceived {
+			p.stats.knownReceived()
+		}
+	}
+	return balancer.PickResult{SubConn: sc, Done: done}, nil
+}
+
+func (p *lbPicker) updateReadySCs(readySCs []balancer.SubConn) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	p.subConns = readySCs
+	p.subConnsNext = p.subConnsNext % len(readySCs)
+}

vendor/google.golang.org/grpc/balancer/grpclb/grpclb_remote_balancer.go

@@ -0,0 +1,410 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpclb
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"sync"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+	timestamppb "github.com/golang/protobuf/ptypes/timestamp"
+	"github.com/google/go-cmp/cmp"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/balancer"
+	lbpb "google.golang.org/grpc/balancer/grpclb/grpc_lb_v1"
+	"google.golang.org/grpc/connectivity"
+	"google.golang.org/grpc/internal/backoff"
+	"google.golang.org/grpc/internal/channelz"
+	imetadata "google.golang.org/grpc/internal/metadata"
+	"google.golang.org/grpc/keepalive"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/resolver"
+)
+
+// processServerList updates balancer's internal state, create/remove SubConns
+// and regenerates picker using the received serverList.
+func (lb *lbBalancer) processServerList(l *lbpb.ServerList) {
+	if logger.V(2) {
+		logger.Infof("lbBalancer: processing server list: %+v", l)
+	}
+	lb.mu.Lock()
+	defer lb.mu.Unlock()
+
+	// Set serverListReceived to true so fallback will not take effect if it has
+	// not hit timeout.
+	lb.serverListReceived = true
+
+	// If the new server list == old server list, do nothing.
+	if cmp.Equal(lb.fullServerList, l.Servers, cmp.Comparer(proto.Equal)) {
+		if logger.V(2) {
+			logger.Infof("lbBalancer: new serverlist same as the previous one, ignoring")
+		}
+		return
+	}
+	lb.fullServerList = l.Servers
+
+	var backendAddrs []resolver.Address
+	for i, s := range l.Servers {
+		if s.Drop {
+			continue
+		}
+
+		md := metadata.Pairs(lbTokenKey, s.LoadBalanceToken)
+		ip := net.IP(s.IpAddress)
+		ipStr := ip.String()
+		if ip.To4() == nil {
+			// Add square brackets to ipv6 addresses, otherwise net.Dial() and
+			// net.SplitHostPort() will return too many colons error.
+			ipStr = fmt.Sprintf("[%s]", ipStr)
+		}
+		addr := imetadata.Set(resolver.Address{Addr: fmt.Sprintf("%s:%d", ipStr, s.Port)}, md)
+		if logger.V(2) {
+			logger.Infof("lbBalancer: server list entry[%d]: ipStr:|%s|, port:|%d|, load balancer token:|%v|",
+				i, ipStr, s.Port, s.LoadBalanceToken)
+		}
+		backendAddrs = append(backendAddrs, addr)
+	}
+
+	// Call refreshSubConns to create/remove SubConns.  If we are in fallback,
+	// this is also exiting fallback.
+	lb.refreshSubConns(backendAddrs, false, lb.usePickFirst)
+}
+
+// refreshSubConns creates/removes SubConns with backendAddrs, and refreshes
+// balancer state and picker.
+//
+// Caller must hold lb.mu.
+func (lb *lbBalancer) refreshSubConns(backendAddrs []resolver.Address, fallback bool, pickFirst bool) {
+	opts := balancer.NewSubConnOptions{}
+	if !fallback {
+		opts.CredsBundle = lb.grpclbBackendCreds
+	}
+
+	lb.backendAddrs = backendAddrs
+	lb.backendAddrsWithoutMetadata = nil
+
+	fallbackModeChanged := lb.inFallback != fallback
+	lb.inFallback = fallback
+	if fallbackModeChanged && lb.inFallback {
+		// Clear previous received list when entering fallback, so if the server
+		// comes back and sends the same list again, the new addresses will be
+		// used.
+		lb.fullServerList = nil
+	}
+
+	balancingPolicyChanged := lb.usePickFirst != pickFirst
+	oldUsePickFirst := lb.usePickFirst
+	lb.usePickFirst = pickFirst
+
+	if fallbackModeChanged || balancingPolicyChanged {
+		// Remove all SubConns when switching balancing policy or switching
+		// fallback mode.
+		//
+		// For fallback mode switching with pickfirst, we want to recreate the
+		// SubConn because the creds could be different.
+		for a, sc := range lb.subConns {
+			if oldUsePickFirst {
+				// If old SubConn were created for pickfirst, bypass cache and
+				// remove directly.
+				lb.cc.cc.RemoveSubConn(sc)
+			} else {
+				lb.cc.RemoveSubConn(sc)
+			}
+			delete(lb.subConns, a)
+		}
+	}
+
+	if lb.usePickFirst {
+		var sc balancer.SubConn
+		for _, sc = range lb.subConns {
+			break
+		}
+		if sc != nil {
+			lb.cc.cc.UpdateAddresses(sc, backendAddrs)
+			sc.Connect()
+			return
+		}
+		// This bypasses the cc wrapper with SubConn cache.
+		sc, err := lb.cc.cc.NewSubConn(backendAddrs, opts)
+		if err != nil {
+			logger.Warningf("grpclb: failed to create new SubConn: %v", err)
+			return
+		}
+		sc.Connect()
+		lb.subConns[backendAddrs[0]] = sc
+		lb.scStates[sc] = connectivity.Idle
+		return
+	}
+
+	// addrsSet is the set converted from backendAddrsWithoutMetadata, it's used to quick
+	// lookup for an address.
+	addrsSet := make(map[resolver.Address]struct{})
+	// Create new SubConns.
+	for _, addr := range backendAddrs {
+		addrWithoutAttrs := addr
+		addrWithoutAttrs.Attributes = nil
+		addrsSet[addrWithoutAttrs] = struct{}{}
+		lb.backendAddrsWithoutMetadata = append(lb.backendAddrsWithoutMetadata, addrWithoutAttrs)
+
+		if _, ok := lb.subConns[addrWithoutAttrs]; !ok {
+			// Use addrWithMD to create the SubConn.
+			sc, err := lb.cc.NewSubConn([]resolver.Address{addr}, opts)
+			if err != nil {
+				logger.Warningf("grpclb: failed to create new SubConn: %v", err)
+				continue
+			}
+			lb.subConns[addrWithoutAttrs] = sc // Use the addr without MD as key for the map.
+			if _, ok := lb.scStates[sc]; !ok {
+				// Only set state of new sc to IDLE. The state could already be
+				// READY for cached SubConns.
+				lb.scStates[sc] = connectivity.Idle
+			}
+			sc.Connect()
+		}
+	}
+
+	for a, sc := range lb.subConns {
+		// a was removed by resolver.
+		if _, ok := addrsSet[a]; !ok {
+			lb.cc.RemoveSubConn(sc)
+			delete(lb.subConns, a)
+			// Keep the state of this sc in b.scStates until sc's state becomes Shutdown.
+			// The entry will be deleted in UpdateSubConnState.
+		}
+	}
+
+	// Regenerate and update picker after refreshing subconns because with
+	// cache, even if SubConn was newed/removed, there might be no state
+	// changes (the subconn will be kept in cache, not actually
+	// newed/removed).
+	lb.updateStateAndPicker(true, true)
+}
+
+type remoteBalancerCCWrapper struct {
+	cc      *grpc.ClientConn
+	lb      *lbBalancer
+	backoff backoff.Strategy
+	done    chan struct{}
+
+	// waitgroup to wait for all goroutines to exit.
+	wg sync.WaitGroup
+}
+
+func (lb *lbBalancer) newRemoteBalancerCCWrapper() {
+	var dopts []grpc.DialOption
+	if creds := lb.opt.DialCreds; creds != nil {
+		dopts = append(dopts, grpc.WithTransportCredentials(creds))
+	} else if bundle := lb.grpclbClientConnCreds; bundle != nil {
+		dopts = append(dopts, grpc.WithCredentialsBundle(bundle))
+	} else {
+		dopts = append(dopts, grpc.WithInsecure())
+	}
+	if lb.opt.Dialer != nil {
+		dopts = append(dopts, grpc.WithContextDialer(lb.opt.Dialer))
+	}
+	if lb.opt.CustomUserAgent != "" {
+		dopts = append(dopts, grpc.WithUserAgent(lb.opt.CustomUserAgent))
+	}
+	// Explicitly set pickfirst as the balancer.
+	dopts = append(dopts, grpc.WithDefaultServiceConfig(`{"loadBalancingPolicy":"pick_first"}`))
+	dopts = append(dopts, grpc.WithResolvers(lb.manualResolver))
+	if channelz.IsOn() {
+		dopts = append(dopts, grpc.WithChannelzParentID(lb.opt.ChannelzParentID))
+	}
+
+	// Enable Keepalive for grpclb client.
+	dopts = append(dopts, grpc.WithKeepaliveParams(keepalive.ClientParameters{
+		Time:                20 * time.Second,
+		Timeout:             10 * time.Second,
+		PermitWithoutStream: true,
+	}))
+
+	// The dial target is not important.
+	//
+	// The grpclb server addresses will set field ServerName, and creds will
+	// receive ServerName as authority.
+	cc, err := grpc.DialContext(context.Background(), lb.manualResolver.Scheme()+":///grpclb.subClientConn", dopts...)
+	if err != nil {
+		logger.Fatalf("failed to dial: %v", err)
+	}
+	ccw := &remoteBalancerCCWrapper{
+		cc:      cc,
+		lb:      lb,
+		backoff: lb.backoff,
+		done:    make(chan struct{}),
+	}
+	lb.ccRemoteLB = ccw
+	ccw.wg.Add(1)
+	go ccw.watchRemoteBalancer()
+}
+
+// close closed the ClientConn to remote balancer, and waits until all
+// goroutines to finish.
+func (ccw *remoteBalancerCCWrapper) close() {
+	close(ccw.done)
+	ccw.cc.Close()
+	ccw.wg.Wait()
+}
+
+func (ccw *remoteBalancerCCWrapper) readServerList(s *balanceLoadClientStream) error {
+	for {
+		reply, err := s.Recv()
+		if err != nil {
+			if err == io.EOF {
+				return errServerTerminatedConnection
+			}
+			return fmt.Errorf("grpclb: failed to recv server list: %v", err)
+		}
+		if serverList := reply.GetServerList(); serverList != nil {
+			ccw.lb.processServerList(serverList)
+		}
+		if reply.GetFallbackResponse() != nil {
+			// Eagerly enter fallback
+			ccw.lb.mu.Lock()
+			ccw.lb.refreshSubConns(ccw.lb.resolvedBackendAddrs, true, ccw.lb.usePickFirst)
+			ccw.lb.mu.Unlock()
+		}
+	}
+}
+
+func (ccw *remoteBalancerCCWrapper) sendLoadReport(s *balanceLoadClientStream, interval time.Duration) {
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+	lastZero := false
+	for {
+		select {
+		case <-ticker.C:
+		case <-s.Context().Done():
+			return
+		}
+		stats := ccw.lb.clientStats.toClientStats()
+		zero := isZeroStats(stats)
+		if zero && lastZero {
+			// Quash redundant empty load reports.
+			continue
+		}
+		lastZero = zero
+		t := time.Now()
+		stats.Timestamp = &timestamppb.Timestamp{
+			Seconds: t.Unix(),
+			Nanos:   int32(t.Nanosecond()),
+		}
+		if err := s.Send(&lbpb.LoadBalanceRequest{
+			LoadBalanceRequestType: &lbpb.LoadBalanceRequest_ClientStats{
+				ClientStats: stats,
+			},
+		}); err != nil {
+			return
+		}
+	}
+}
+
+func (ccw *remoteBalancerCCWrapper) callRemoteBalancer() (backoff bool, _ error) {
+	lbClient := &loadBalancerClient{cc: ccw.cc}
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	stream, err := lbClient.BalanceLoad(ctx, grpc.WaitForReady(true))
+	if err != nil {
+		return true, fmt.Errorf("grpclb: failed to perform RPC to the remote balancer %v", err)
+	}
+	ccw.lb.mu.Lock()
+	ccw.lb.remoteBalancerConnected = true
+	ccw.lb.mu.Unlock()
+
+	// grpclb handshake on the stream.
+	initReq := &lbpb.LoadBalanceRequest{
+		LoadBalanceRequestType: &lbpb.LoadBalanceRequest_InitialRequest{
+			InitialRequest: &lbpb.InitialLoadBalanceRequest{
+				Name: ccw.lb.target,
+			},
+		},
+	}
+	if err := stream.Send(initReq); err != nil {
+		return true, fmt.Errorf("grpclb: failed to send init request: %v", err)
+	}
+	reply, err := stream.Recv()
+	if err != nil {
+		return true, fmt.Errorf("grpclb: failed to recv init response: %v", err)
+	}
+	initResp := reply.GetInitialResponse()
+	if initResp == nil {
+		return true, fmt.Errorf("grpclb: reply from remote balancer did not include initial response")
+	}
+
+	ccw.wg.Add(1)
+	go func() {
+		defer ccw.wg.Done()
+		if d := convertDuration(initResp.ClientStatsReportInterval); d > 0 {
+			ccw.sendLoadReport(stream, d)
+		}
+	}()
+	// No backoff if init req/resp handshake was successful.
+	return false, ccw.readServerList(stream)
+}
+
+func (ccw *remoteBalancerCCWrapper) watchRemoteBalancer() {
+	defer ccw.wg.Done()
+	var retryCount int
+	for {
+		doBackoff, err := ccw.callRemoteBalancer()
+		select {
+		case <-ccw.done:
+			return
+		default:
+			if err != nil {
+				if err == errServerTerminatedConnection {
+					logger.Info(err)
+				} else {
+					logger.Warning(err)
+				}
+			}
+		}
+		// Trigger a re-resolve when the stream errors.
+		ccw.lb.cc.cc.ResolveNow(resolver.ResolveNowOptions{})
+
+		ccw.lb.mu.Lock()
+		ccw.lb.remoteBalancerConnected = false
+		ccw.lb.fullServerList = nil
+		// Enter fallback when connection to remote balancer is lost, and the
+		// aggregated state is not Ready.
+		if !ccw.lb.inFallback && ccw.lb.state != connectivity.Ready {
+			// Entering fallback.
+			ccw.lb.refreshSubConns(ccw.lb.resolvedBackendAddrs, true, ccw.lb.usePickFirst)
+		}
+		ccw.lb.mu.Unlock()
+
+		if !doBackoff {
+			retryCount = 0
+			continue
+		}
+
+		timer := time.NewTimer(ccw.backoff.Backoff(retryCount)) // Copy backoff
+		select {
+		case <-timer.C:
+		case <-ccw.done:
+			timer.Stop()
+			return
+		}
+		retryCount++
+	}
+}

vendor/google.golang.org/grpc/balancer/grpclb/grpclb_util.go

@@ -0,0 +1,208 @@
+/*
+ *
+ * Copyright 2016 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpclb
+
+import (
+	"fmt"
+	"sync"
+	"time"
+
+	"google.golang.org/grpc/balancer"
+	"google.golang.org/grpc/resolver"
+)
+
+// The parent ClientConn should re-resolve when grpclb loses connection to the
+// remote balancer. When the ClientConn inside grpclb gets a TransientFailure,
+// it calls lbManualResolver.ResolveNow(), which calls parent ClientConn's
+// ResolveNow, and eventually results in re-resolve happening in parent
+// ClientConn's resolver (DNS for example).
+//
+//                          parent
+//                          ClientConn
+//  +-----------------------------------------------------------------+
+//  |             parent          +---------------------------------+ |
+//  | DNS         ClientConn      |  grpclb                         | |
+//  | resolver    balancerWrapper |                                 | |
+//  | +              +            |    grpclb          grpclb       | |
+//  | |              |            |    ManualResolver  ClientConn   | |
+//  | |              |            |     +              +            | |
+//  | |              |            |     |              | Transient  | |
+//  | |              |            |     |              | Failure    | |
+//  | |              |            |     |  <---------  |            | |
+//  | |              | <--------------- |  ResolveNow  |            | |
+//  | |  <---------  | ResolveNow |     |              |            | |
+//  | |  ResolveNow  |            |     |              |            | |
+//  | |              |            |     |              |            | |
+//  | +              +            |     +              +            | |
+//  |                             +---------------------------------+ |
+//  +-----------------------------------------------------------------+
+
+// lbManualResolver is used by the ClientConn inside grpclb. It's a manual
+// resolver with a special ResolveNow() function.
+//
+// When ResolveNow() is called, it calls ResolveNow() on the parent ClientConn,
+// so when grpclb client lose contact with remote balancers, the parent
+// ClientConn's resolver will re-resolve.
+type lbManualResolver struct {
+	scheme string
+	ccr    resolver.ClientConn
+
+	ccb balancer.ClientConn
+}
+
+func (r *lbManualResolver) Build(_ resolver.Target, cc resolver.ClientConn, _ resolver.BuildOptions) (resolver.Resolver, error) {
+	r.ccr = cc
+	return r, nil
+}
+
+func (r *lbManualResolver) Scheme() string {
+	return r.scheme
+}
+
+// ResolveNow calls resolveNow on the parent ClientConn.
+func (r *lbManualResolver) ResolveNow(o resolver.ResolveNowOptions) {
+	r.ccb.ResolveNow(o)
+}
+
+// Close is a noop for Resolver.
+func (*lbManualResolver) Close() {}
+
+// UpdateState calls cc.UpdateState.
+func (r *lbManualResolver) UpdateState(s resolver.State) {
+	r.ccr.UpdateState(s)
+}
+
+const subConnCacheTime = time.Second * 10
+
+// lbCacheClientConn is a wrapper balancer.ClientConn with a SubConn cache.
+// SubConns will be kept in cache for subConnCacheTime before being removed.
+//
+// Its new and remove methods are updated to do cache first.
+type lbCacheClientConn struct {
+	cc      balancer.ClientConn
+	timeout time.Duration
+
+	mu sync.Mutex
+	// subConnCache only keeps subConns that are being deleted.
+	subConnCache  map[resolver.Address]*subConnCacheEntry
+	subConnToAddr map[balancer.SubConn]resolver.Address
+}
+
+type subConnCacheEntry struct {
+	sc balancer.SubConn
+
+	cancel        func()
+	abortDeleting bool
+}
+
+func newLBCacheClientConn(cc balancer.ClientConn) *lbCacheClientConn {
+	return &lbCacheClientConn{
+		cc:            cc,
+		timeout:       subConnCacheTime,
+		subConnCache:  make(map[resolver.Address]*subConnCacheEntry),
+		subConnToAddr: make(map[balancer.SubConn]resolver.Address),
+	}
+}
+
+func (ccc *lbCacheClientConn) NewSubConn(addrs []resolver.Address, opts balancer.NewSubConnOptions) (balancer.SubConn, error) {
+	if len(addrs) != 1 {
+		return nil, fmt.Errorf("grpclb calling NewSubConn with addrs of length %v", len(addrs))
+	}
+	addrWithoutAttrs := addrs[0]
+	addrWithoutAttrs.Attributes = nil
+
+	ccc.mu.Lock()
+	defer ccc.mu.Unlock()
+	if entry, ok := ccc.subConnCache[addrWithoutAttrs]; ok {
+		// If entry is in subConnCache, the SubConn was being deleted.
+		// cancel function will never be nil.
+		entry.cancel()
+		delete(ccc.subConnCache, addrWithoutAttrs)
+		return entry.sc, nil
+	}
+
+	scNew, err := ccc.cc.NewSubConn(addrs, opts)
+	if err != nil {
+		return nil, err
+	}
+
+	ccc.subConnToAddr[scNew] = addrWithoutAttrs
+	return scNew, nil
+}
+
+func (ccc *lbCacheClientConn) RemoveSubConn(sc balancer.SubConn) {
+	ccc.mu.Lock()
+	defer ccc.mu.Unlock()
+	addr, ok := ccc.subConnToAddr[sc]
+	if !ok {
+		return
+	}
+
+	if entry, ok := ccc.subConnCache[addr]; ok {
+		if entry.sc != sc {
+			// This could happen if NewSubConn was called multiple times for the
+			// same address, and those SubConns are all removed. We remove sc
+			// immediately here.
+			delete(ccc.subConnToAddr, sc)
+			ccc.cc.RemoveSubConn(sc)
+		}
+		return
+	}
+
+	entry := &subConnCacheEntry{
+		sc: sc,
+	}
+	ccc.subConnCache[addr] = entry
+
+	timer := time.AfterFunc(ccc.timeout, func() {
+		ccc.mu.Lock()
+		defer ccc.mu.Unlock()
+		if entry.abortDeleting {
+			return
+		}
+		ccc.cc.RemoveSubConn(sc)
+		delete(ccc.subConnToAddr, sc)
+		delete(ccc.subConnCache, addr)
+	})
+	entry.cancel = func() {
+		if !timer.Stop() {
+			// If stop was not successful, the timer has fired (this can only
+			// happen in a race). But the deleting function is blocked on ccc.mu
+			// because the mutex was held by the caller of this function.
+			//
+			// Set abortDeleting to true to abort the deleting function. When
+			// the lock is released, the deleting function will acquire the
+			// lock, check the value of abortDeleting and return.
+			entry.abortDeleting = true
+		}
+	}
+}
+
+func (ccc *lbCacheClientConn) UpdateState(s balancer.State) {
+	ccc.cc.UpdateState(s)
+}
+
+func (ccc *lbCacheClientConn) close() {
+	ccc.mu.Lock()
+	// Only cancel all existing timers. There's no need to remove SubConns.
+	for _, entry := range ccc.subConnCache {
+		entry.cancel()
+	}
+	ccc.mu.Unlock()
+}

vendor/google.golang.org/grpc/credentials/alts/alts.go

@@ -0,0 +1,332 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package alts implements the ALTS credential support by gRPC library, which
+// encapsulates all the state needed by a client to authenticate with a server
+// using ALTS and make various assertions, e.g., about the client's identity,
+// role, or whether it is authorized to make a particular call.
+// This package is experimental.
+package alts
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"sync"
+	"time"
+
+	"google.golang.org/grpc/credentials"
+	core "google.golang.org/grpc/credentials/alts/internal"
+	"google.golang.org/grpc/credentials/alts/internal/handshaker"
+	"google.golang.org/grpc/credentials/alts/internal/handshaker/service"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/googlecloud"
+)
+
+const (
+	// hypervisorHandshakerServiceAddress represents the default ALTS gRPC
+	// handshaker service address in the hypervisor.
+	hypervisorHandshakerServiceAddress = "metadata.google.internal.:8080"
+	// defaultTimeout specifies the server handshake timeout.
+	defaultTimeout = 30.0 * time.Second
+	// The following constants specify the minimum and maximum acceptable
+	// protocol versions.
+	protocolVersionMaxMajor = 2
+	protocolVersionMaxMinor = 1
+	protocolVersionMinMajor = 2
+	protocolVersionMinMinor = 1
+)
+
+var (
+	vmOnGCP       bool
+	once          sync.Once
+	maxRPCVersion = &altspb.RpcProtocolVersions_Version{
+		Major: protocolVersionMaxMajor,
+		Minor: protocolVersionMaxMinor,
+	}
+	minRPCVersion = &altspb.RpcProtocolVersions_Version{
+		Major: protocolVersionMinMajor,
+		Minor: protocolVersionMinMinor,
+	}
+	// ErrUntrustedPlatform is returned from ClientHandshake and
+	// ServerHandshake is running on a platform where the trustworthiness of
+	// the handshaker service is not guaranteed.
+	ErrUntrustedPlatform = errors.New("ALTS: untrusted platform. ALTS is only supported on GCP")
+	logger               = grpclog.Component("alts")
+)
+
+// AuthInfo exposes security information from the ALTS handshake to the
+// application. This interface is to be implemented by ALTS. Users should not
+// need a brand new implementation of this interface. For situations like
+// testing, any new implementation should embed this interface. This allows
+// ALTS to add new methods to this interface.
+type AuthInfo interface {
+	// ApplicationProtocol returns application protocol negotiated for the
+	// ALTS connection.
+	ApplicationProtocol() string
+	// RecordProtocol returns the record protocol negotiated for the ALTS
+	// connection.
+	RecordProtocol() string
+	// SecurityLevel returns the security level of the created ALTS secure
+	// channel.
+	SecurityLevel() altspb.SecurityLevel
+	// PeerServiceAccount returns the peer service account.
+	PeerServiceAccount() string
+	// LocalServiceAccount returns the local service account.
+	LocalServiceAccount() string
+	// PeerRPCVersions returns the RPC version supported by the peer.
+	PeerRPCVersions() *altspb.RpcProtocolVersions
+}
+
+// ClientOptions contains the client-side options of an ALTS channel. These
+// options will be passed to the underlying ALTS handshaker.
+type ClientOptions struct {
+	// TargetServiceAccounts contains a list of expected target service
+	// accounts.
+	TargetServiceAccounts []string
+	// HandshakerServiceAddress represents the ALTS handshaker gRPC service
+	// address to connect to.
+	HandshakerServiceAddress string
+}
+
+// DefaultClientOptions creates a new ClientOptions object with the default
+// values.
+func DefaultClientOptions() *ClientOptions {
+	return &ClientOptions{
+		HandshakerServiceAddress: hypervisorHandshakerServiceAddress,
+	}
+}
+
+// ServerOptions contains the server-side options of an ALTS channel. These
+// options will be passed to the underlying ALTS handshaker.
+type ServerOptions struct {
+	// HandshakerServiceAddress represents the ALTS handshaker gRPC service
+	// address to connect to.
+	HandshakerServiceAddress string
+}
+
+// DefaultServerOptions creates a new ServerOptions object with the default
+// values.
+func DefaultServerOptions() *ServerOptions {
+	return &ServerOptions{
+		HandshakerServiceAddress: hypervisorHandshakerServiceAddress,
+	}
+}
+
+// altsTC is the credentials required for authenticating a connection using ALTS.
+// It implements credentials.TransportCredentials interface.
+type altsTC struct {
+	info      *credentials.ProtocolInfo
+	side      core.Side
+	accounts  []string
+	hsAddress string
+}
+
+// NewClientCreds constructs a client-side ALTS TransportCredentials object.
+func NewClientCreds(opts *ClientOptions) credentials.TransportCredentials {
+	return newALTS(core.ClientSide, opts.TargetServiceAccounts, opts.HandshakerServiceAddress)
+}
+
+// NewServerCreds constructs a server-side ALTS TransportCredentials object.
+func NewServerCreds(opts *ServerOptions) credentials.TransportCredentials {
+	return newALTS(core.ServerSide, nil, opts.HandshakerServiceAddress)
+}
+
+func newALTS(side core.Side, accounts []string, hsAddress string) credentials.TransportCredentials {
+	once.Do(func() {
+		vmOnGCP = googlecloud.OnGCE()
+	})
+	if hsAddress == "" {
+		hsAddress = hypervisorHandshakerServiceAddress
+	}
+	return &altsTC{
+		info: &credentials.ProtocolInfo{
+			SecurityProtocol: "alts",
+			SecurityVersion:  "1.0",
+		},
+		side:      side,
+		accounts:  accounts,
+		hsAddress: hsAddress,
+	}
+}
+
+// ClientHandshake implements the client side handshake protocol.
+func (g *altsTC) ClientHandshake(ctx context.Context, addr string, rawConn net.Conn) (_ net.Conn, _ credentials.AuthInfo, err error) {
+	if !vmOnGCP {
+		return nil, nil, ErrUntrustedPlatform
+	}
+
+	// Connecting to ALTS handshaker service.
+	hsConn, err := service.Dial(g.hsAddress)
+	if err != nil {
+		return nil, nil, err
+	}
+	// Do not close hsConn since it is shared with other handshakes.
+
+	// Possible context leak:
+	// The cancel function for the child context we create will only be
+	// called a non-nil error is returned.
+	var cancel context.CancelFunc
+	ctx, cancel = context.WithCancel(ctx)
+	defer func() {
+		if err != nil {
+			cancel()
+		}
+	}()
+
+	opts := handshaker.DefaultClientHandshakerOptions()
+	opts.TargetName = addr
+	opts.TargetServiceAccounts = g.accounts
+	opts.RPCVersions = &altspb.RpcProtocolVersions{
+		MaxRpcVersion: maxRPCVersion,
+		MinRpcVersion: minRPCVersion,
+	}
+	chs, err := handshaker.NewClientHandshaker(ctx, hsConn, rawConn, opts)
+	if err != nil {
+		return nil, nil, err
+	}
+	defer func() {
+		if err != nil {
+			chs.Close()
+		}
+	}()
+	secConn, authInfo, err := chs.ClientHandshake(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+	altsAuthInfo, ok := authInfo.(AuthInfo)
+	if !ok {
+		return nil, nil, errors.New("client-side auth info is not of type alts.AuthInfo")
+	}
+	match, _ := checkRPCVersions(opts.RPCVersions, altsAuthInfo.PeerRPCVersions())
+	if !match {
+		return nil, nil, fmt.Errorf("server-side RPC versions are not compatible with this client, local versions: %v, peer versions: %v", opts.RPCVersions, altsAuthInfo.PeerRPCVersions())
+	}
+	return secConn, authInfo, nil
+}
+
+// ServerHandshake implements the server side ALTS handshaker.
+func (g *altsTC) ServerHandshake(rawConn net.Conn) (_ net.Conn, _ credentials.AuthInfo, err error) {
+	if !vmOnGCP {
+		return nil, nil, ErrUntrustedPlatform
+	}
+	// Connecting to ALTS handshaker service.
+	hsConn, err := service.Dial(g.hsAddress)
+	if err != nil {
+		return nil, nil, err
+	}
+	// Do not close hsConn since it's shared with other handshakes.
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTimeout)
+	defer cancel()
+	opts := handshaker.DefaultServerHandshakerOptions()
+	opts.RPCVersions = &altspb.RpcProtocolVersions{
+		MaxRpcVersion: maxRPCVersion,
+		MinRpcVersion: minRPCVersion,
+	}
+	shs, err := handshaker.NewServerHandshaker(ctx, hsConn, rawConn, opts)
+	if err != nil {
+		return nil, nil, err
+	}
+	defer func() {
+		if err != nil {
+			shs.Close()
+		}
+	}()
+	secConn, authInfo, err := shs.ServerHandshake(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+	altsAuthInfo, ok := authInfo.(AuthInfo)
+	if !ok {
+		return nil, nil, errors.New("server-side auth info is not of type alts.AuthInfo")
+	}
+	match, _ := checkRPCVersions(opts.RPCVersions, altsAuthInfo.PeerRPCVersions())
+	if !match {
+		return nil, nil, fmt.Errorf("client-side RPC versions is not compatible with this server, local versions: %v, peer versions: %v", opts.RPCVersions, altsAuthInfo.PeerRPCVersions())
+	}
+	return secConn, authInfo, nil
+}
+
+func (g *altsTC) Info() credentials.ProtocolInfo {
+	return *g.info
+}
+
+func (g *altsTC) Clone() credentials.TransportCredentials {
+	info := *g.info
+	var accounts []string
+	if g.accounts != nil {
+		accounts = make([]string, len(g.accounts))
+		copy(accounts, g.accounts)
+	}
+	return &altsTC{
+		info:      &info,
+		side:      g.side,
+		hsAddress: g.hsAddress,
+		accounts:  accounts,
+	}
+}
+
+func (g *altsTC) OverrideServerName(serverNameOverride string) error {
+	g.info.ServerName = serverNameOverride
+	return nil
+}
+
+// compareRPCVersion returns 0 if v1 == v2, 1 if v1 > v2 and -1 if v1 < v2.
+func compareRPCVersions(v1, v2 *altspb.RpcProtocolVersions_Version) int {
+	switch {
+	case v1.GetMajor() > v2.GetMajor(),
+		v1.GetMajor() == v2.GetMajor() && v1.GetMinor() > v2.GetMinor():
+		return 1
+	case v1.GetMajor() < v2.GetMajor(),
+		v1.GetMajor() == v2.GetMajor() && v1.GetMinor() < v2.GetMinor():
+		return -1
+	}
+	return 0
+}
+
+// checkRPCVersions performs a version check between local and peer rpc protocol
+// versions. This function returns true if the check passes which means both
+// parties agreed on a common rpc protocol to use, and false otherwise. The
+// function also returns the highest common RPC protocol version both parties
+// agreed on.
+func checkRPCVersions(local, peer *altspb.RpcProtocolVersions) (bool, *altspb.RpcProtocolVersions_Version) {
+	if local == nil || peer == nil {
+		logger.Error("invalid checkRPCVersions argument, either local or peer is nil.")
+		return false, nil
+	}
+
+	// maxCommonVersion is MIN(local.max, peer.max).
+	maxCommonVersion := local.GetMaxRpcVersion()
+	if compareRPCVersions(local.GetMaxRpcVersion(), peer.GetMaxRpcVersion()) > 0 {
+		maxCommonVersion = peer.GetMaxRpcVersion()
+	}
+
+	// minCommonVersion is MAX(local.min, peer.min).
+	minCommonVersion := peer.GetMinRpcVersion()
+	if compareRPCVersions(local.GetMinRpcVersion(), peer.GetMinRpcVersion()) > 0 {
+		minCommonVersion = local.GetMinRpcVersion()
+	}
+
+	if compareRPCVersions(maxCommonVersion, minCommonVersion) < 0 {
+		return false, nil
+	}
+	return true, maxCommonVersion
+}

vendor/google.golang.org/grpc/credentials/alts/internal/authinfo/authinfo.go

@@ -0,0 +1,95 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package authinfo provide authentication information returned by handshakers.
+package authinfo
+
+import (
+	"google.golang.org/grpc/credentials"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
+)
+
+var _ credentials.AuthInfo = (*altsAuthInfo)(nil)
+
+// altsAuthInfo exposes security information from the ALTS handshake to the
+// application. altsAuthInfo is immutable and implements credentials.AuthInfo.
+type altsAuthInfo struct {
+	p *altspb.AltsContext
+	credentials.CommonAuthInfo
+}
+
+// New returns a new altsAuthInfo object given handshaker results.
+func New(result *altspb.HandshakerResult) credentials.AuthInfo {
+	return newAuthInfo(result)
+}
+
+func newAuthInfo(result *altspb.HandshakerResult) *altsAuthInfo {
+	return &altsAuthInfo{
+		p: &altspb.AltsContext{
+			ApplicationProtocol: result.GetApplicationProtocol(),
+			RecordProtocol:      result.GetRecordProtocol(),
+			// TODO: assign security level from result.
+			SecurityLevel:       altspb.SecurityLevel_INTEGRITY_AND_PRIVACY,
+			PeerServiceAccount:  result.GetPeerIdentity().GetServiceAccount(),
+			LocalServiceAccount: result.GetLocalIdentity().GetServiceAccount(),
+			PeerRpcVersions:     result.GetPeerRpcVersions(),
+			PeerAttributes:      result.GetPeerIdentity().GetAttributes(),
+		},
+		CommonAuthInfo: credentials.CommonAuthInfo{SecurityLevel: credentials.PrivacyAndIntegrity},
+	}
+}
+
+// AuthType identifies the context as providing ALTS authentication information.
+func (s *altsAuthInfo) AuthType() string {
+	return "alts"
+}
+
+// ApplicationProtocol returns the context's application protocol.
+func (s *altsAuthInfo) ApplicationProtocol() string {
+	return s.p.GetApplicationProtocol()
+}
+
+// RecordProtocol returns the context's record protocol.
+func (s *altsAuthInfo) RecordProtocol() string {
+	return s.p.GetRecordProtocol()
+}
+
+// SecurityLevel returns the context's security level.
+func (s *altsAuthInfo) SecurityLevel() altspb.SecurityLevel {
+	return s.p.GetSecurityLevel()
+}
+
+// PeerServiceAccount returns the context's peer service account.
+func (s *altsAuthInfo) PeerServiceAccount() string {
+	return s.p.GetPeerServiceAccount()
+}
+
+// LocalServiceAccount returns the context's local service account.
+func (s *altsAuthInfo) LocalServiceAccount() string {
+	return s.p.GetLocalServiceAccount()
+}
+
+// PeerRPCVersions returns the context's peer RPC versions.
+func (s *altsAuthInfo) PeerRPCVersions() *altspb.RpcProtocolVersions {
+	return s.p.GetPeerRpcVersions()
+}
+
+// PeerAttributes returns the context's peer attributes.
+func (s *altsAuthInfo) PeerAttributes() map[string]string {
+	return s.p.GetPeerAttributes()
+}

vendor/google.golang.org/grpc/credentials/alts/internal/common.go

@@ -0,0 +1,67 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package internal contains common core functionality for ALTS.
+package internal
+
+import (
+	"context"
+	"net"
+
+	"google.golang.org/grpc/credentials"
+)
+
+const (
+	// ClientSide identifies the client in this communication.
+	ClientSide Side = iota
+	// ServerSide identifies the server in this communication.
+	ServerSide
+)
+
+// PeerNotRespondingError is returned when a peer server is not responding
+// after a channel has been established. It is treated as a temporary connection
+// error and re-connection to the server should be attempted.
+var PeerNotRespondingError = &peerNotRespondingError{}
+
+// Side identifies the party's role: client or server.
+type Side int
+
+type peerNotRespondingError struct{}
+
+// Return an error message for the purpose of logging.
+func (e *peerNotRespondingError) Error() string {
+	return "peer server is not responding and re-connection should be attempted."
+}
+
+// Temporary indicates if this connection error is temporary or fatal.
+func (e *peerNotRespondingError) Temporary() bool {
+	return true
+}
+
+// Handshaker defines a ALTS handshaker interface.
+type Handshaker interface {
+	// ClientHandshake starts and completes a client-side handshaking and
+	// returns a secure connection and corresponding auth information.
+	ClientHandshake(ctx context.Context) (net.Conn, credentials.AuthInfo, error)
+	// ServerHandshake starts and completes a server-side handshaking and
+	// returns a secure connection and corresponding auth information.
+	ServerHandshake(ctx context.Context) (net.Conn, credentials.AuthInfo, error)
+	// Close terminates the Handshaker. It should be called when the caller
+	// obtains the secure connection.
+	Close()
+}

vendor/google.golang.org/grpc/credentials/alts/internal/conn/aeadrekey.go

@@ -0,0 +1,131 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package conn
+
+import (
+	"bytes"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/binary"
+	"fmt"
+	"strconv"
+)
+
+// rekeyAEAD holds the necessary information for an AEAD based on
+// AES-GCM that performs nonce-based key derivation and XORs the
+// nonce with a random mask.
+type rekeyAEAD struct {
+	kdfKey     []byte
+	kdfCounter []byte
+	nonceMask  []byte
+	nonceBuf   []byte
+	gcmAEAD    cipher.AEAD
+}
+
+// KeySizeError signals that the given key does not have the correct size.
+type KeySizeError int
+
+func (k KeySizeError) Error() string {
+	return "alts/conn: invalid key size " + strconv.Itoa(int(k))
+}
+
+// newRekeyAEAD creates a new instance of aes128gcm with rekeying.
+// The key argument should be 44 bytes, the first 32 bytes are used as a key
+// for HKDF-expand and the remainining 12 bytes are used as a random mask for
+// the counter.
+func newRekeyAEAD(key []byte) (*rekeyAEAD, error) {
+	k := len(key)
+	if k != kdfKeyLen+nonceLen {
+		return nil, KeySizeError(k)
+	}
+	return &rekeyAEAD{
+		kdfKey:     key[:kdfKeyLen],
+		kdfCounter: make([]byte, kdfCounterLen),
+		nonceMask:  key[kdfKeyLen:],
+		nonceBuf:   make([]byte, nonceLen),
+		gcmAEAD:    nil,
+	}, nil
+}
+
+// Seal rekeys if nonce[2:8] is different than in the last call, masks the nonce,
+// and calls Seal for aes128gcm.
+func (s *rekeyAEAD) Seal(dst, nonce, plaintext, additionalData []byte) []byte {
+	if err := s.rekeyIfRequired(nonce); err != nil {
+		panic(fmt.Sprintf("Rekeying failed with: %s", err.Error()))
+	}
+	maskNonce(s.nonceBuf, nonce, s.nonceMask)
+	return s.gcmAEAD.Seal(dst, s.nonceBuf, plaintext, additionalData)
+}
+
+// Open rekeys if nonce[2:8] is different than in the last call, masks the nonce,
+// and calls Open for aes128gcm.
+func (s *rekeyAEAD) Open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) {
+	if err := s.rekeyIfRequired(nonce); err != nil {
+		return nil, err
+	}
+	maskNonce(s.nonceBuf, nonce, s.nonceMask)
+	return s.gcmAEAD.Open(dst, s.nonceBuf, ciphertext, additionalData)
+}
+
+// rekeyIfRequired creates a new aes128gcm AEAD if the existing AEAD is nil
+// or cannot be used with given nonce.
+func (s *rekeyAEAD) rekeyIfRequired(nonce []byte) error {
+	newKdfCounter := nonce[kdfCounterOffset : kdfCounterOffset+kdfCounterLen]
+	if s.gcmAEAD != nil && bytes.Equal(newKdfCounter, s.kdfCounter) {
+		return nil
+	}
+	copy(s.kdfCounter, newKdfCounter)
+	a, err := aes.NewCipher(hkdfExpand(s.kdfKey, s.kdfCounter))
+	if err != nil {
+		return err
+	}
+	s.gcmAEAD, err = cipher.NewGCM(a)
+	return err
+}
+
+// maskNonce XORs the given nonce with the mask and stores the result in dst.
+func maskNonce(dst, nonce, mask []byte) {
+	nonce1 := binary.LittleEndian.Uint64(nonce[:sizeUint64])
+	nonce2 := binary.LittleEndian.Uint32(nonce[sizeUint64:])
+	mask1 := binary.LittleEndian.Uint64(mask[:sizeUint64])
+	mask2 := binary.LittleEndian.Uint32(mask[sizeUint64:])
+	binary.LittleEndian.PutUint64(dst[:sizeUint64], nonce1^mask1)
+	binary.LittleEndian.PutUint32(dst[sizeUint64:], nonce2^mask2)
+}
+
+// NonceSize returns the required nonce size.
+func (s *rekeyAEAD) NonceSize() int {
+	return s.gcmAEAD.NonceSize()
+}
+
+// Overhead returns the ciphertext overhead.
+func (s *rekeyAEAD) Overhead() int {
+	return s.gcmAEAD.Overhead()
+}
+
+// hkdfExpand computes the first 16 bytes of the HKDF-expand function
+// defined in RFC5869.
+func hkdfExpand(key, info []byte) []byte {
+	mac := hmac.New(sha256.New, key)
+	mac.Write(info)
+	mac.Write([]byte{0x01}[:])
+	return mac.Sum(nil)[:aeadKeyLen]
+}

vendor/google.golang.org/grpc/credentials/alts/internal/conn/aes128gcm.go

@@ -0,0 +1,105 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package conn
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+
+	core "google.golang.org/grpc/credentials/alts/internal"
+)
+
+const (
+	// Overflow length n in bytes, never encrypt more than 2^(n*8) frames (in
+	// each direction).
+	overflowLenAES128GCM = 5
+)
+
+// aes128gcm is the struct that holds necessary information for ALTS record.
+// The counter value is NOT included in the payload during the encryption and
+// decryption operations.
+type aes128gcm struct {
+	// inCounter is used in ALTS record to check that incoming counters are
+	// as expected, since ALTS record guarantees that messages are unwrapped
+	// in the same order that the peer wrapped them.
+	inCounter  Counter
+	outCounter Counter
+	aead       cipher.AEAD
+}
+
+// NewAES128GCM creates an instance that uses aes128gcm for ALTS record.
+func NewAES128GCM(side core.Side, key []byte) (ALTSRecordCrypto, error) {
+	c, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	a, err := cipher.NewGCM(c)
+	if err != nil {
+		return nil, err
+	}
+	return &aes128gcm{
+		inCounter:  NewInCounter(side, overflowLenAES128GCM),
+		outCounter: NewOutCounter(side, overflowLenAES128GCM),
+		aead:       a,
+	}, nil
+}
+
+// Encrypt is the encryption function. dst can contain bytes at the beginning of
+// the ciphertext that will not be encrypted but will be authenticated. If dst
+// has enough capacity to hold these bytes, the ciphertext and the tag, no
+// allocation and copy operations will be performed. dst and plaintext do not
+// overlap.
+func (s *aes128gcm) Encrypt(dst, plaintext []byte) ([]byte, error) {
+	// If we need to allocate an output buffer, we want to include space for
+	// GCM tag to avoid forcing ALTS record to reallocate as well.
+	dlen := len(dst)
+	dst, out := SliceForAppend(dst, len(plaintext)+GcmTagSize)
+	seq, err := s.outCounter.Value()
+	if err != nil {
+		return nil, err
+	}
+	data := out[:len(plaintext)]
+	copy(data, plaintext) // data may alias plaintext
+
+	// Seal appends the ciphertext and the tag to its first argument and
+	// returns the updated slice. However, SliceForAppend above ensures that
+	// dst has enough capacity to avoid a reallocation and copy due to the
+	// append.
+	dst = s.aead.Seal(dst[:dlen], seq, data, nil)
+	s.outCounter.Inc()
+	return dst, nil
+}
+
+func (s *aes128gcm) EncryptionOverhead() int {
+	return GcmTagSize
+}
+
+func (s *aes128gcm) Decrypt(dst, ciphertext []byte) ([]byte, error) {
+	seq, err := s.inCounter.Value()
+	if err != nil {
+		return nil, err
+	}
+	// If dst is equal to ciphertext[:0], ciphertext storage is reused.
+	plaintext, err := s.aead.Open(dst, seq, ciphertext, nil)
+	if err != nil {
+		return nil, ErrAuth
+	}
+	s.inCounter.Inc()
+	return plaintext, nil
+}

vendor/google.golang.org/grpc/credentials/alts/internal/conn/aes128gcmrekey.go

@@ -0,0 +1,116 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package conn
+
+import (
+	"crypto/cipher"
+
+	core "google.golang.org/grpc/credentials/alts/internal"
+)
+
+const (
+	// Overflow length n in bytes, never encrypt more than 2^(n*8) frames (in
+	// each direction).
+	overflowLenAES128GCMRekey = 8
+	nonceLen                  = 12
+	aeadKeyLen                = 16
+	kdfKeyLen                 = 32
+	kdfCounterOffset          = 2
+	kdfCounterLen             = 6
+	sizeUint64                = 8
+)
+
+// aes128gcmRekey is the struct that holds necessary information for ALTS record.
+// The counter value is NOT included in the payload during the encryption and
+// decryption operations.
+type aes128gcmRekey struct {
+	// inCounter is used in ALTS record to check that incoming counters are
+	// as expected, since ALTS record guarantees that messages are unwrapped
+	// in the same order that the peer wrapped them.
+	inCounter  Counter
+	outCounter Counter
+	inAEAD     cipher.AEAD
+	outAEAD    cipher.AEAD
+}
+
+// NewAES128GCMRekey creates an instance that uses aes128gcm with rekeying
+// for ALTS record. The key argument should be 44 bytes, the first 32 bytes
+// are used as a key for HKDF-expand and the remainining 12 bytes are used
+// as a random mask for the counter.
+func NewAES128GCMRekey(side core.Side, key []byte) (ALTSRecordCrypto, error) {
+	inCounter := NewInCounter(side, overflowLenAES128GCMRekey)
+	outCounter := NewOutCounter(side, overflowLenAES128GCMRekey)
+	inAEAD, err := newRekeyAEAD(key)
+	if err != nil {
+		return nil, err
+	}
+	outAEAD, err := newRekeyAEAD(key)
+	if err != nil {
+		return nil, err
+	}
+	return &aes128gcmRekey{
+		inCounter,
+		outCounter,
+		inAEAD,
+		outAEAD,
+	}, nil
+}
+
+// Encrypt is the encryption function. dst can contain bytes at the beginning of
+// the ciphertext that will not be encrypted but will be authenticated. If dst
+// has enough capacity to hold these bytes, the ciphertext and the tag, no
+// allocation and copy operations will be performed. dst and plaintext do not
+// overlap.
+func (s *aes128gcmRekey) Encrypt(dst, plaintext []byte) ([]byte, error) {
+	// If we need to allocate an output buffer, we want to include space for
+	// GCM tag to avoid forcing ALTS record to reallocate as well.
+	dlen := len(dst)
+	dst, out := SliceForAppend(dst, len(plaintext)+GcmTagSize)
+	seq, err := s.outCounter.Value()
+	if err != nil {
+		return nil, err
+	}
+	data := out[:len(plaintext)]
+	copy(data, plaintext) // data may alias plaintext
+
+	// Seal appends the ciphertext and the tag to its first argument and
+	// returns the updated slice. However, SliceForAppend above ensures that
+	// dst has enough capacity to avoid a reallocation and copy due to the
+	// append.
+	dst = s.outAEAD.Seal(dst[:dlen], seq, data, nil)
+	s.outCounter.Inc()
+	return dst, nil
+}
+
+func (s *aes128gcmRekey) EncryptionOverhead() int {
+	return GcmTagSize
+}
+
+func (s *aes128gcmRekey) Decrypt(dst, ciphertext []byte) ([]byte, error) {
+	seq, err := s.inCounter.Value()
+	if err != nil {
+		return nil, err
+	}
+	plaintext, err := s.inAEAD.Open(dst, seq, ciphertext, nil)
+	if err != nil {
+		return nil, ErrAuth
+	}
+	s.inCounter.Inc()
+	return plaintext, nil
+}

vendor/google.golang.org/grpc/credentials/alts/internal/conn/common.go

@@ -0,0 +1,70 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package conn
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+)
+
+const (
+	// GcmTagSize is the GCM tag size is the difference in length between
+	// plaintext and ciphertext. From crypto/cipher/gcm.go in Go crypto
+	// library.
+	GcmTagSize = 16
+)
+
+// ErrAuth occurs on authentication failure.
+var ErrAuth = errors.New("message authentication failed")
+
+// SliceForAppend takes a slice and a requested number of bytes. It returns a
+// slice with the contents of the given slice followed by that many bytes and a
+// second slice that aliases into it and contains only the extra bytes. If the
+// original slice has sufficient capacity then no allocation is performed.
+func SliceForAppend(in []byte, n int) (head, tail []byte) {
+	if total := len(in) + n; cap(in) >= total {
+		head = in[:total]
+	} else {
+		head = make([]byte, total)
+		copy(head, in)
+	}
+	tail = head[len(in):]
+	return head, tail
+}
+
+// ParseFramedMsg parse the provided buffer and returns a frame of the format
+// msgLength+msg and any remaining bytes in that buffer.
+func ParseFramedMsg(b []byte, maxLen uint32) ([]byte, []byte, error) {
+	// If the size field is not complete, return the provided buffer as
+	// remaining buffer.
+	if len(b) < MsgLenFieldSize {
+		return nil, b, nil
+	}
+	msgLenField := b[:MsgLenFieldSize]
+	length := binary.LittleEndian.Uint32(msgLenField)
+	if length > maxLen {
+		return nil, nil, fmt.Errorf("received the frame length %d larger than the limit %d", length, maxLen)
+	}
+	if len(b) < int(length)+4 { // account for the first 4 msg length bytes.
+		// Frame is not complete yet.
+		return nil, b, nil
+	}
+	return b[:MsgLenFieldSize+length], b[MsgLenFieldSize+length:], nil
+}

vendor/google.golang.org/grpc/credentials/alts/internal/conn/counter.go

@@ -0,0 +1,62 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package conn
+
+import (
+	"errors"
+)
+
+const counterLen = 12
+
+var (
+	errInvalidCounter = errors.New("invalid counter")
+)
+
+// Counter is a 96-bit, little-endian counter.
+type Counter struct {
+	value       [counterLen]byte
+	invalid     bool
+	overflowLen int
+}
+
+// Value returns the current value of the counter as a byte slice.
+func (c *Counter) Value() ([]byte, error) {
+	if c.invalid {
+		return nil, errInvalidCounter
+	}
+	return c.value[:], nil
+}
+
+// Inc increments the counter and checks for overflow.
+func (c *Counter) Inc() {
+	// If the counter is already invalid, there is no need to increase it.
+	if c.invalid {
+		return
+	}
+	i := 0
+	for ; i < c.overflowLen; i++ {
+		c.value[i]++
+		if c.value[i] != 0 {
+			break
+		}
+	}
+	if i == c.overflowLen {
+		c.invalid = true
+	}
+}

vendor/google.golang.org/grpc/credentials/alts/internal/conn/record.go

@@ -0,0 +1,275 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package conn contains an implementation of a secure channel created by gRPC
+// handshakers.
+package conn
+
+import (
+	"encoding/binary"
+	"fmt"
+	"math"
+	"net"
+
+	core "google.golang.org/grpc/credentials/alts/internal"
+)
+
+// ALTSRecordCrypto is the interface for gRPC ALTS record protocol.
+type ALTSRecordCrypto interface {
+	// Encrypt encrypts the plaintext and computes the tag (if any) of dst
+	// and plaintext. dst and plaintext may fully overlap or not at all.
+	Encrypt(dst, plaintext []byte) ([]byte, error)
+	// EncryptionOverhead returns the tag size (if any) in bytes.
+	EncryptionOverhead() int
+	// Decrypt decrypts ciphertext and verify the tag (if any). dst and
+	// ciphertext may alias exactly or not at all. To reuse ciphertext's
+	// storage for the decrypted output, use ciphertext[:0] as dst.
+	Decrypt(dst, ciphertext []byte) ([]byte, error)
+}
+
+// ALTSRecordFunc is a function type for factory functions that create
+// ALTSRecordCrypto instances.
+type ALTSRecordFunc func(s core.Side, keyData []byte) (ALTSRecordCrypto, error)
+
+const (
+	// MsgLenFieldSize is the byte size of the frame length field of a
+	// framed message.
+	MsgLenFieldSize = 4
+	// The byte size of the message type field of a framed message.
+	msgTypeFieldSize = 4
+	// The bytes size limit for a ALTS record message.
+	altsRecordLengthLimit = 1024 * 1024 // 1 MiB
+	// The default bytes size of a ALTS record message.
+	altsRecordDefaultLength = 4 * 1024 // 4KiB
+	// Message type value included in ALTS record framing.
+	altsRecordMsgType = uint32(0x06)
+	// The initial write buffer size.
+	altsWriteBufferInitialSize = 32 * 1024 // 32KiB
+	// The maximum write buffer size. This *must* be multiple of
+	// altsRecordDefaultLength.
+	altsWriteBufferMaxSize = 512 * 1024 // 512KiB
+)
+
+var (
+	protocols = make(map[string]ALTSRecordFunc)
+)
+
+// RegisterProtocol register a ALTS record encryption protocol.
+func RegisterProtocol(protocol string, f ALTSRecordFunc) error {
+	if _, ok := protocols[protocol]; ok {
+		return fmt.Errorf("protocol %v is already registered", protocol)
+	}
+	protocols[protocol] = f
+	return nil
+}
+
+// conn represents a secured connection. It implements the net.Conn interface.
+type conn struct {
+	net.Conn
+	crypto ALTSRecordCrypto
+	// buf holds data that has been read from the connection and decrypted,
+	// but has not yet been returned by Read.
+	buf                []byte
+	payloadLengthLimit int
+	// protected holds data read from the network but have not yet been
+	// decrypted. This data might not compose a complete frame.
+	protected []byte
+	// writeBuf is a buffer used to contain encrypted frames before being
+	// written to the network.
+	writeBuf []byte
+	// nextFrame stores the next frame (in protected buffer) info.
+	nextFrame []byte
+	// overhead is the calculated overhead of each frame.
+	overhead int
+}
+
+// NewConn creates a new secure channel instance given the other party role and
+// handshaking result.
+func NewConn(c net.Conn, side core.Side, recordProtocol string, key []byte, protected []byte) (net.Conn, error) {
+	newCrypto := protocols[recordProtocol]
+	if newCrypto == nil {
+		return nil, fmt.Errorf("negotiated unknown next_protocol %q", recordProtocol)
+	}
+	crypto, err := newCrypto(side, key)
+	if err != nil {
+		return nil, fmt.Errorf("protocol %q: %v", recordProtocol, err)
+	}
+	overhead := MsgLenFieldSize + msgTypeFieldSize + crypto.EncryptionOverhead()
+	payloadLengthLimit := altsRecordDefaultLength - overhead
+	var protectedBuf []byte
+	if protected == nil {
+		// We pre-allocate protected to be of size
+		// 2*altsRecordDefaultLength-1 during initialization. We only
+		// read from the network into protected when protected does not
+		// contain a complete frame, which is at most
+		// altsRecordDefaultLength-1 (bytes). And we read at most
+		// altsRecordDefaultLength (bytes) data into protected at one
+		// time. Therefore, 2*altsRecordDefaultLength-1 is large enough
+		// to buffer data read from the network.
+		protectedBuf = make([]byte, 0, 2*altsRecordDefaultLength-1)
+	} else {
+		protectedBuf = make([]byte, len(protected))
+		copy(protectedBuf, protected)
+	}
+
+	altsConn := &conn{
+		Conn:               c,
+		crypto:             crypto,
+		payloadLengthLimit: payloadLengthLimit,
+		protected:          protectedBuf,
+		writeBuf:           make([]byte, altsWriteBufferInitialSize),
+		nextFrame:          protectedBuf,
+		overhead:           overhead,
+	}
+	return altsConn, nil
+}
+
+// Read reads and decrypts a frame from the underlying connection, and copies the
+// decrypted payload into b. If the size of the payload is greater than len(b),
+// Read retains the remaining bytes in an internal buffer, and subsequent calls
+// to Read will read from this buffer until it is exhausted.
+func (p *conn) Read(b []byte) (n int, err error) {
+	if len(p.buf) == 0 {
+		var framedMsg []byte
+		framedMsg, p.nextFrame, err = ParseFramedMsg(p.nextFrame, altsRecordLengthLimit)
+		if err != nil {
+			return n, err
+		}
+		// Check whether the next frame to be decrypted has been
+		// completely received yet.
+		if len(framedMsg) == 0 {
+			copy(p.protected, p.nextFrame)
+			p.protected = p.protected[:len(p.nextFrame)]
+			// Always copy next incomplete frame to the beginning of
+			// the protected buffer and reset nextFrame to it.
+			p.nextFrame = p.protected
+		}
+		// Check whether a complete frame has been received yet.
+		for len(framedMsg) == 0 {
+			if len(p.protected) == cap(p.protected) {
+				tmp := make([]byte, len(p.protected), cap(p.protected)+altsRecordDefaultLength)
+				copy(tmp, p.protected)
+				p.protected = tmp
+			}
+			n, err = p.Conn.Read(p.protected[len(p.protected):min(cap(p.protected), len(p.protected)+altsRecordDefaultLength)])
+			if err != nil {
+				return 0, err
+			}
+			p.protected = p.protected[:len(p.protected)+n]
+			framedMsg, p.nextFrame, err = ParseFramedMsg(p.protected, altsRecordLengthLimit)
+			if err != nil {
+				return 0, err
+			}
+		}
+		// Now we have a complete frame, decrypted it.
+		msg := framedMsg[MsgLenFieldSize:]
+		msgType := binary.LittleEndian.Uint32(msg[:msgTypeFieldSize])
+		if msgType&0xff != altsRecordMsgType {
+			return 0, fmt.Errorf("received frame with incorrect message type %v, expected lower byte %v",
+				msgType, altsRecordMsgType)
+		}
+		ciphertext := msg[msgTypeFieldSize:]
+
+		// Decrypt requires that if the dst and ciphertext alias, they
+		// must alias exactly. Code here used to use msg[:0], but msg
+		// starts MsgLenFieldSize+msgTypeFieldSize bytes earlier than
+		// ciphertext, so they alias inexactly. Using ciphertext[:0]
+		// arranges the appropriate aliasing without needing to copy
+		// ciphertext or use a separate destination buffer. For more info
+		// check: https://golang.org/pkg/crypto/cipher/#AEAD.
+		p.buf, err = p.crypto.Decrypt(ciphertext[:0], ciphertext)
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	n = copy(b, p.buf)
+	p.buf = p.buf[n:]
+	return n, nil
+}
+
+// Write encrypts, frames, and writes bytes from b to the underlying connection.
+func (p *conn) Write(b []byte) (n int, err error) {
+	n = len(b)
+	// Calculate the output buffer size with framing and encryption overhead.
+	numOfFrames := int(math.Ceil(float64(len(b)) / float64(p.payloadLengthLimit)))
+	size := len(b) + numOfFrames*p.overhead
+	// If writeBuf is too small, increase its size up to the maximum size.
+	partialBSize := len(b)
+	if size > altsWriteBufferMaxSize {
+		size = altsWriteBufferMaxSize
+		const numOfFramesInMaxWriteBuf = altsWriteBufferMaxSize / altsRecordDefaultLength
+		partialBSize = numOfFramesInMaxWriteBuf * p.payloadLengthLimit
+	}
+	if len(p.writeBuf) < size {
+		p.writeBuf = make([]byte, size)
+	}
+
+	for partialBStart := 0; partialBStart < len(b); partialBStart += partialBSize {
+		partialBEnd := partialBStart + partialBSize
+		if partialBEnd > len(b) {
+			partialBEnd = len(b)
+		}
+		partialB := b[partialBStart:partialBEnd]
+		writeBufIndex := 0
+		for len(partialB) > 0 {
+			payloadLen := len(partialB)
+			if payloadLen > p.payloadLengthLimit {
+				payloadLen = p.payloadLengthLimit
+			}
+			buf := partialB[:payloadLen]
+			partialB = partialB[payloadLen:]
+
+			// Write buffer contains: length, type, payload, and tag
+			// if any.
+
+			// 1. Fill in type field.
+			msg := p.writeBuf[writeBufIndex+MsgLenFieldSize:]
+			binary.LittleEndian.PutUint32(msg, altsRecordMsgType)
+
+			// 2. Encrypt the payload and create a tag if any.
+			msg, err = p.crypto.Encrypt(msg[:msgTypeFieldSize], buf)
+			if err != nil {
+				return n, err
+			}
+
+			// 3. Fill in the size field.
+			binary.LittleEndian.PutUint32(p.writeBuf[writeBufIndex:], uint32(len(msg)))
+
+			// 4. Increase writeBufIndex.
+			writeBufIndex += len(buf) + p.overhead
+		}
+		nn, err := p.Conn.Write(p.writeBuf[:writeBufIndex])
+		if err != nil {
+			// We need to calculate the actual data size that was
+			// written. This means we need to remove header,
+			// encryption overheads, and any partially-written
+			// frame data.
+			numOfWrittenFrames := int(math.Floor(float64(nn) / float64(altsRecordDefaultLength)))
+			return partialBStart + numOfWrittenFrames*p.payloadLengthLimit, err
+		}
+	}
+	return n, nil
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}

vendor/google.golang.org/grpc/credentials/alts/internal/conn/utils.go

@@ -0,0 +1,63 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package conn
+
+import core "google.golang.org/grpc/credentials/alts/internal"
+
+// NewOutCounter returns an outgoing counter initialized to the starting sequence
+// number for the client/server side of a connection.
+func NewOutCounter(s core.Side, overflowLen int) (c Counter) {
+	c.overflowLen = overflowLen
+	if s == core.ServerSide {
+		// Server counters in ALTS record have the little-endian high bit
+		// set.
+		c.value[counterLen-1] = 0x80
+	}
+	return
+}
+
+// NewInCounter returns an incoming counter initialized to the starting sequence
+// number for the client/server side of a connection. This is used in ALTS record
+// to check that incoming counters are as expected, since ALTS record guarantees
+// that messages are unwrapped in the same order that the peer wrapped them.
+func NewInCounter(s core.Side, overflowLen int) (c Counter) {
+	c.overflowLen = overflowLen
+	if s == core.ClientSide {
+		// Server counters in ALTS record have the little-endian high bit
+		// set.
+		c.value[counterLen-1] = 0x80
+	}
+	return
+}
+
+// CounterFromValue creates a new counter given an initial value.
+func CounterFromValue(value []byte, overflowLen int) (c Counter) {
+	c.overflowLen = overflowLen
+	copy(c.value[:], value)
+	return
+}
+
+// CounterSide returns the connection side (client/server) a sequence counter is
+// associated with.
+func CounterSide(c []byte) core.Side {
+	if c[counterLen-1]&0x80 == 0x80 {
+		return core.ServerSide
+	}
+	return core.ClientSide
+}

vendor/google.golang.org/grpc/credentials/alts/internal/handshaker/handshaker.go

@@ -0,0 +1,375 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package handshaker provides ALTS handshaking functionality for GCP.
+package handshaker
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"sync"
+
+	grpc "google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/credentials"
+	core "google.golang.org/grpc/credentials/alts/internal"
+	"google.golang.org/grpc/credentials/alts/internal/authinfo"
+	"google.golang.org/grpc/credentials/alts/internal/conn"
+	altsgrpc "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
+)
+
+const (
+	// The maximum byte size of receive frames.
+	frameLimit              = 64 * 1024 // 64 KB
+	rekeyRecordProtocolName = "ALTSRP_GCM_AES128_REKEY"
+	// maxPendingHandshakes represents the maximum number of concurrent
+	// handshakes.
+	maxPendingHandshakes = 100
+)
+
+var (
+	hsProtocol      = altspb.HandshakeProtocol_ALTS
+	appProtocols    = []string{"grpc"}
+	recordProtocols = []string{rekeyRecordProtocolName}
+	keyLength       = map[string]int{
+		rekeyRecordProtocolName: 44,
+	}
+	altsRecordFuncs = map[string]conn.ALTSRecordFunc{
+		// ALTS handshaker protocols.
+		rekeyRecordProtocolName: func(s core.Side, keyData []byte) (conn.ALTSRecordCrypto, error) {
+			return conn.NewAES128GCMRekey(s, keyData)
+		},
+	}
+	// control number of concurrent created (but not closed) handshakers.
+	mu                   sync.Mutex
+	concurrentHandshakes = int64(0)
+	// errDropped occurs when maxPendingHandshakes is reached.
+	errDropped = errors.New("maximum number of concurrent ALTS handshakes is reached")
+	// errOutOfBound occurs when the handshake service returns a consumed
+	// bytes value larger than the buffer that was passed to it originally.
+	errOutOfBound = errors.New("handshaker service consumed bytes value is out-of-bound")
+)
+
+func init() {
+	for protocol, f := range altsRecordFuncs {
+		if err := conn.RegisterProtocol(protocol, f); err != nil {
+			panic(err)
+		}
+	}
+}
+
+func acquire() bool {
+	mu.Lock()
+	// If we need n to be configurable, we can pass it as an argument.
+	n := int64(1)
+	success := maxPendingHandshakes-concurrentHandshakes >= n
+	if success {
+		concurrentHandshakes += n
+	}
+	mu.Unlock()
+	return success
+}
+
+func release() {
+	mu.Lock()
+	// If we need n to be configurable, we can pass it as an argument.
+	n := int64(1)
+	concurrentHandshakes -= n
+	if concurrentHandshakes < 0 {
+		mu.Unlock()
+		panic("bad release")
+	}
+	mu.Unlock()
+}
+
+// ClientHandshakerOptions contains the client handshaker options that can
+// provided by the caller.
+type ClientHandshakerOptions struct {
+	// ClientIdentity is the handshaker client local identity.
+	ClientIdentity *altspb.Identity
+	// TargetName is the server service account name for secure name
+	// checking.
+	TargetName string
+	// TargetServiceAccounts contains a list of expected target service
+	// accounts. One of these accounts should match one of the accounts in
+	// the handshaker results. Otherwise, the handshake fails.
+	TargetServiceAccounts []string
+	// RPCVersions specifies the gRPC versions accepted by the client.
+	RPCVersions *altspb.RpcProtocolVersions
+}
+
+// ServerHandshakerOptions contains the server handshaker options that can
+// provided by the caller.
+type ServerHandshakerOptions struct {
+	// RPCVersions specifies the gRPC versions accepted by the server.
+	RPCVersions *altspb.RpcProtocolVersions
+}
+
+// DefaultClientHandshakerOptions returns the default client handshaker options.
+func DefaultClientHandshakerOptions() *ClientHandshakerOptions {
+	return &ClientHandshakerOptions{}
+}
+
+// DefaultServerHandshakerOptions returns the default client handshaker options.
+func DefaultServerHandshakerOptions() *ServerHandshakerOptions {
+	return &ServerHandshakerOptions{}
+}
+
+// TODO: add support for future local and remote endpoint in both client options
+//       and server options (server options struct does not exist now. When
+//       caller can provide endpoints, it should be created.
+
+// altsHandshaker is used to complete a ALTS handshaking between client and
+// server. This handshaker talks to the ALTS handshaker service in the metadata
+// server.
+type altsHandshaker struct {
+	// RPC stream used to access the ALTS Handshaker service.
+	stream altsgrpc.HandshakerService_DoHandshakeClient
+	// the connection to the peer.
+	conn net.Conn
+	// client handshake options.
+	clientOpts *ClientHandshakerOptions
+	// server handshake options.
+	serverOpts *ServerHandshakerOptions
+	// defines the side doing the handshake, client or server.
+	side core.Side
+}
+
+// NewClientHandshaker creates a ALTS handshaker for GCP which contains an RPC
+// stub created using the passed conn and used to talk to the ALTS Handshaker
+// service in the metadata server.
+func NewClientHandshaker(ctx context.Context, conn *grpc.ClientConn, c net.Conn, opts *ClientHandshakerOptions) (core.Handshaker, error) {
+	stream, err := altsgrpc.NewHandshakerServiceClient(conn).DoHandshake(ctx, grpc.WaitForReady(true))
+	if err != nil {
+		return nil, err
+	}
+	return &altsHandshaker{
+		stream:     stream,
+		conn:       c,
+		clientOpts: opts,
+		side:       core.ClientSide,
+	}, nil
+}
+
+// NewServerHandshaker creates a ALTS handshaker for GCP which contains an RPC
+// stub created using the passed conn and used to talk to the ALTS Handshaker
+// service in the metadata server.
+func NewServerHandshaker(ctx context.Context, conn *grpc.ClientConn, c net.Conn, opts *ServerHandshakerOptions) (core.Handshaker, error) {
+	stream, err := altsgrpc.NewHandshakerServiceClient(conn).DoHandshake(ctx, grpc.WaitForReady(true))
+	if err != nil {
+		return nil, err
+	}
+	return &altsHandshaker{
+		stream:     stream,
+		conn:       c,
+		serverOpts: opts,
+		side:       core.ServerSide,
+	}, nil
+}
+
+// ClientHandshake starts and completes a client ALTS handshaking for GCP. Once
+// done, ClientHandshake returns a secure connection.
+func (h *altsHandshaker) ClientHandshake(ctx context.Context) (net.Conn, credentials.AuthInfo, error) {
+	if !acquire() {
+		return nil, nil, errDropped
+	}
+	defer release()
+
+	if h.side != core.ClientSide {
+		return nil, nil, errors.New("only handshakers created using NewClientHandshaker can perform a client handshaker")
+	}
+
+	// Create target identities from service account list.
+	targetIdentities := make([]*altspb.Identity, 0, len(h.clientOpts.TargetServiceAccounts))
+	for _, account := range h.clientOpts.TargetServiceAccounts {
+		targetIdentities = append(targetIdentities, &altspb.Identity{
+			IdentityOneof: &altspb.Identity_ServiceAccount{
+				ServiceAccount: account,
+			},
+		})
+	}
+	req := &altspb.HandshakerReq{
+		ReqOneof: &altspb.HandshakerReq_ClientStart{
+			ClientStart: &altspb.StartClientHandshakeReq{
+				HandshakeSecurityProtocol: hsProtocol,
+				ApplicationProtocols:      appProtocols,
+				RecordProtocols:           recordProtocols,
+				TargetIdentities:          targetIdentities,
+				LocalIdentity:             h.clientOpts.ClientIdentity,
+				TargetName:                h.clientOpts.TargetName,
+				RpcVersions:               h.clientOpts.RPCVersions,
+			},
+		},
+	}
+
+	conn, result, err := h.doHandshake(req)
+	if err != nil {
+		return nil, nil, err
+	}
+	authInfo := authinfo.New(result)
+	return conn, authInfo, nil
+}
+
+// ServerHandshake starts and completes a server ALTS handshaking for GCP. Once
+// done, ServerHandshake returns a secure connection.
+func (h *altsHandshaker) ServerHandshake(ctx context.Context) (net.Conn, credentials.AuthInfo, error) {
+	if !acquire() {
+		return nil, nil, errDropped
+	}
+	defer release()
+
+	if h.side != core.ServerSide {
+		return nil, nil, errors.New("only handshakers created using NewServerHandshaker can perform a server handshaker")
+	}
+
+	p := make([]byte, frameLimit)
+	n, err := h.conn.Read(p)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Prepare server parameters.
+	// TODO: currently only ALTS parameters are provided. Might need to use
+	//       more options in the future.
+	params := make(map[int32]*altspb.ServerHandshakeParameters)
+	params[int32(altspb.HandshakeProtocol_ALTS)] = &altspb.ServerHandshakeParameters{
+		RecordProtocols: recordProtocols,
+	}
+	req := &altspb.HandshakerReq{
+		ReqOneof: &altspb.HandshakerReq_ServerStart{
+			ServerStart: &altspb.StartServerHandshakeReq{
+				ApplicationProtocols: appProtocols,
+				HandshakeParameters:  params,
+				InBytes:              p[:n],
+				RpcVersions:          h.serverOpts.RPCVersions,
+			},
+		},
+	}
+
+	conn, result, err := h.doHandshake(req)
+	if err != nil {
+		return nil, nil, err
+	}
+	authInfo := authinfo.New(result)
+	return conn, authInfo, nil
+}
+
+func (h *altsHandshaker) doHandshake(req *altspb.HandshakerReq) (net.Conn, *altspb.HandshakerResult, error) {
+	resp, err := h.accessHandshakerService(req)
+	if err != nil {
+		return nil, nil, err
+	}
+	// Check of the returned status is an error.
+	if resp.GetStatus() != nil {
+		if got, want := resp.GetStatus().Code, uint32(codes.OK); got != want {
+			return nil, nil, fmt.Errorf("%v", resp.GetStatus().Details)
+		}
+	}
+
+	var extra []byte
+	if req.GetServerStart() != nil {
+		if resp.GetBytesConsumed() > uint32(len(req.GetServerStart().GetInBytes())) {
+			return nil, nil, errOutOfBound
+		}
+		extra = req.GetServerStart().GetInBytes()[resp.GetBytesConsumed():]
+	}
+	result, extra, err := h.processUntilDone(resp, extra)
+	if err != nil {
+		return nil, nil, err
+	}
+	// The handshaker returns a 128 bytes key. It should be truncated based
+	// on the returned record protocol.
+	keyLen, ok := keyLength[result.RecordProtocol]
+	if !ok {
+		return nil, nil, fmt.Errorf("unknown resulted record protocol %v", result.RecordProtocol)
+	}
+	sc, err := conn.NewConn(h.conn, h.side, result.GetRecordProtocol(), result.KeyData[:keyLen], extra)
+	if err != nil {
+		return nil, nil, err
+	}
+	return sc, result, nil
+}
+
+func (h *altsHandshaker) accessHandshakerService(req *altspb.HandshakerReq) (*altspb.HandshakerResp, error) {
+	if err := h.stream.Send(req); err != nil {
+		return nil, err
+	}
+	resp, err := h.stream.Recv()
+	if err != nil {
+		return nil, err
+	}
+	return resp, nil
+}
+
+// processUntilDone processes the handshake until the handshaker service returns
+// the results. Handshaker service takes care of frame parsing, so we read
+// whatever received from the network and send it to the handshaker service.
+func (h *altsHandshaker) processUntilDone(resp *altspb.HandshakerResp, extra []byte) (*altspb.HandshakerResult, []byte, error) {
+	for {
+		if len(resp.OutFrames) > 0 {
+			if _, err := h.conn.Write(resp.OutFrames); err != nil {
+				return nil, nil, err
+			}
+		}
+		if resp.Result != nil {
+			return resp.Result, extra, nil
+		}
+		buf := make([]byte, frameLimit)
+		n, err := h.conn.Read(buf)
+		if err != nil && err != io.EOF {
+			return nil, nil, err
+		}
+		// If there is nothing to send to the handshaker service, and
+		// nothing is received from the peer, then we are stuck.
+		// This covers the case when the peer is not responding. Note
+		// that handshaker service connection issues are caught in
+		// accessHandshakerService before we even get here.
+		if len(resp.OutFrames) == 0 && n == 0 {
+			return nil, nil, core.PeerNotRespondingError
+		}
+		// Append extra bytes from the previous interaction with the
+		// handshaker service with the current buffer read from conn.
+		p := append(extra, buf[:n]...)
+		// From here on, p and extra point to the same slice.
+		resp, err = h.accessHandshakerService(&altspb.HandshakerReq{
+			ReqOneof: &altspb.HandshakerReq_Next{
+				Next: &altspb.NextHandshakeMessageReq{
+					InBytes: p,
+				},
+			},
+		})
+		if err != nil {
+			return nil, nil, err
+		}
+		// Set extra based on handshaker service response.
+		if resp.GetBytesConsumed() > uint32(len(p)) {
+			return nil, nil, errOutOfBound
+		}
+		extra = p[resp.GetBytesConsumed():]
+	}
+}
+
+// Close terminates the Handshaker. It should be called when the caller obtains
+// the secure connection.
+func (h *altsHandshaker) Close() {
+	h.stream.CloseSend()
+}

vendor/google.golang.org/grpc/credentials/alts/internal/handshaker/service/service.go

@@ -0,0 +1,59 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package service manages connections between the VM application and the ALTS
+// handshaker service.
+package service
+
+import (
+	"sync"
+
+	grpc "google.golang.org/grpc"
+)
+
+var (
+	// mu guards hsConnMap and hsDialer.
+	mu sync.Mutex
+	// hsConn represents a mapping from a hypervisor handshaker service address
+	// to a corresponding connection to a hypervisor handshaker service
+	// instance.
+	hsConnMap = make(map[string]*grpc.ClientConn)
+	// hsDialer will be reassigned in tests.
+	hsDialer = grpc.Dial
+)
+
+// Dial dials the handshake service in the hypervisor. If a connection has
+// already been established, this function returns it. Otherwise, a new
+// connection is created.
+func Dial(hsAddress string) (*grpc.ClientConn, error) {
+	mu.Lock()
+	defer mu.Unlock()
+
+	hsConn, ok := hsConnMap[hsAddress]
+	if !ok {
+		// Create a new connection to the handshaker service. Note that
+		// this connection stays open until the application is closed.
+		var err error
+		hsConn, err = hsDialer(hsAddress, grpc.WithInsecure())
+		if err != nil {
+			return nil, err
+		}
+		hsConnMap[hsAddress] = hsConn
+	}
+	return hsConn, nil
+}

vendor/google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp/altscontext.pb.go

@@ -0,0 +1,264 @@
+// Copyright 2018 The gRPC Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// The canonical version of this proto can be found at
+// https://github.com/grpc/grpc-proto/blob/master/grpc/gcp/altscontext.proto
+
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.25.0
+// 	protoc        v3.14.0
+// source: grpc/gcp/altscontext.proto
+
+package grpc_gcp
+
+import (
+	proto "github.com/golang/protobuf/proto"
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+// This is a compile-time assertion that a sufficiently up-to-date version
+// of the legacy proto package is being used.
+const _ = proto.ProtoPackageIsVersion4
+
+type AltsContext struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// The application protocol negotiated for this connection.
+	ApplicationProtocol string `protobuf:"bytes,1,opt,name=application_protocol,json=applicationProtocol,proto3" json:"application_protocol,omitempty"`
+	// The record protocol negotiated for this connection.
+	RecordProtocol string `protobuf:"bytes,2,opt,name=record_protocol,json=recordProtocol,proto3" json:"record_protocol,omitempty"`
+	// The security level of the created secure channel.
+	SecurityLevel SecurityLevel `protobuf:"varint,3,opt,name=security_level,json=securityLevel,proto3,enum=grpc.gcp.SecurityLevel" json:"security_level,omitempty"`
+	// The peer service account.
+	PeerServiceAccount string `protobuf:"bytes,4,opt,name=peer_service_account,json=peerServiceAccount,proto3" json:"peer_service_account,omitempty"`
+	// The local service account.
+	LocalServiceAccount string `protobuf:"bytes,5,opt,name=local_service_account,json=localServiceAccount,proto3" json:"local_service_account,omitempty"`
+	// The RPC protocol versions supported by the peer.
+	PeerRpcVersions *RpcProtocolVersions `protobuf:"bytes,6,opt,name=peer_rpc_versions,json=peerRpcVersions,proto3" json:"peer_rpc_versions,omitempty"`
+	// Additional attributes of the peer.
+	PeerAttributes map[string]string `protobuf:"bytes,7,rep,name=peer_attributes,json=peerAttributes,proto3" json:"peer_attributes,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"bytes,2,opt,name=value,proto3"`
+}
+
+func (x *AltsContext) Reset() {
+	*x = AltsContext{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_gcp_altscontext_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *AltsContext) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*AltsContext) ProtoMessage() {}
+
+func (x *AltsContext) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_gcp_altscontext_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use AltsContext.ProtoReflect.Descriptor instead.
+func (*AltsContext) Descriptor() ([]byte, []int) {
+	return file_grpc_gcp_altscontext_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *AltsContext) GetApplicationProtocol() string {
+	if x != nil {
+		return x.ApplicationProtocol
+	}
+	return ""
+}
+
+func (x *AltsContext) GetRecordProtocol() string {
+	if x != nil {
+		return x.RecordProtocol
+	}
+	return ""
+}
+
+func (x *AltsContext) GetSecurityLevel() SecurityLevel {
+	if x != nil {
+		return x.SecurityLevel
+	}
+	return SecurityLevel_SECURITY_NONE
+}
+
+func (x *AltsContext) GetPeerServiceAccount() string {
+	if x != nil {
+		return x.PeerServiceAccount
+	}
+	return ""
+}
+
+func (x *AltsContext) GetLocalServiceAccount() string {
+	if x != nil {
+		return x.LocalServiceAccount
+	}
+	return ""
+}
+
+func (x *AltsContext) GetPeerRpcVersions() *RpcProtocolVersions {
+	if x != nil {
+		return x.PeerRpcVersions
+	}
+	return nil
+}
+
+func (x *AltsContext) GetPeerAttributes() map[string]string {
+	if x != nil {
+		return x.PeerAttributes
+	}
+	return nil
+}
+
+var File_grpc_gcp_altscontext_proto protoreflect.FileDescriptor
+
+var file_grpc_gcp_altscontext_proto_rawDesc = []byte{
+	0x0a, 0x1a, 0x67, 0x72, 0x70, 0x63, 0x2f, 0x67, 0x63, 0x70, 0x2f, 0x61, 0x6c, 0x74, 0x73, 0x63,
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+	0x73, 0x1a, 0x41, 0x0a, 0x13, 0x50, 0x65, 0x65, 0x72, 0x41, 0x74, 0x74, 0x72, 0x69, 0x62, 0x75,
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+	0x01, 0x20, 0x01, 0x28, 0x09, 0x52, 0x03, 0x6b, 0x65, 0x79, 0x12, 0x14, 0x0a, 0x05, 0x76, 0x61,
+	0x6c, 0x75, 0x65, 0x18, 0x02, 0x20, 0x01, 0x28, 0x09, 0x52, 0x05, 0x76, 0x61, 0x6c, 0x75, 0x65,
+	0x3a, 0x02, 0x38, 0x01, 0x42, 0x6c, 0x0a, 0x15, 0x69, 0x6f, 0x2e, 0x67, 0x72, 0x70, 0x63, 0x2e,
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+	0x01, 0x5a, 0x3f, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61, 0x6e, 0x67,
+	0x2e, 0x6f, 0x72, 0x67, 0x2f, 0x67, 0x72, 0x70, 0x63, 0x2f, 0x63, 0x72, 0x65, 0x64, 0x65, 0x6e,
+	0x74, 0x69, 0x61, 0x6c, 0x73, 0x2f, 0x61, 0x6c, 0x74, 0x73, 0x2f, 0x69, 0x6e, 0x74, 0x65, 0x72,
+	0x6e, 0x61, 0x6c, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2f, 0x67, 0x72, 0x70, 0x63, 0x5f, 0x67,
+	0x63, 0x70, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_grpc_gcp_altscontext_proto_rawDescOnce sync.Once
+	file_grpc_gcp_altscontext_proto_rawDescData = file_grpc_gcp_altscontext_proto_rawDesc
+)
+
+func file_grpc_gcp_altscontext_proto_rawDescGZIP() []byte {
+	file_grpc_gcp_altscontext_proto_rawDescOnce.Do(func() {
+		file_grpc_gcp_altscontext_proto_rawDescData = protoimpl.X.CompressGZIP(file_grpc_gcp_altscontext_proto_rawDescData)
+	})
+	return file_grpc_gcp_altscontext_proto_rawDescData
+}
+
+var file_grpc_gcp_altscontext_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
+var file_grpc_gcp_altscontext_proto_goTypes = []interface{}{
+	(*AltsContext)(nil),         // 0: grpc.gcp.AltsContext
+	nil,                         // 1: grpc.gcp.AltsContext.PeerAttributesEntry
+	(SecurityLevel)(0),          // 2: grpc.gcp.SecurityLevel
+	(*RpcProtocolVersions)(nil), // 3: grpc.gcp.RpcProtocolVersions
+}
+var file_grpc_gcp_altscontext_proto_depIdxs = []int32{
+	2, // 0: grpc.gcp.AltsContext.security_level:type_name -> grpc.gcp.SecurityLevel
+	3, // 1: grpc.gcp.AltsContext.peer_rpc_versions:type_name -> grpc.gcp.RpcProtocolVersions
+	1, // 2: grpc.gcp.AltsContext.peer_attributes:type_name -> grpc.gcp.AltsContext.PeerAttributesEntry
+	3, // [3:3] is the sub-list for method output_type
+	3, // [3:3] is the sub-list for method input_type
+	3, // [3:3] is the sub-list for extension type_name
+	3, // [3:3] is the sub-list for extension extendee
+	0, // [0:3] is the sub-list for field type_name
+}
+
+func init() { file_grpc_gcp_altscontext_proto_init() }
+func file_grpc_gcp_altscontext_proto_init() {
+	if File_grpc_gcp_altscontext_proto != nil {
+		return
+	}
+	file_grpc_gcp_transport_security_common_proto_init()
+	if !protoimpl.UnsafeEnabled {
+		file_grpc_gcp_altscontext_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*AltsContext); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_grpc_gcp_altscontext_proto_rawDesc,
+			NumEnums:      0,
+			NumMessages:   2,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_grpc_gcp_altscontext_proto_goTypes,
+		DependencyIndexes: file_grpc_gcp_altscontext_proto_depIdxs,
+		MessageInfos:      file_grpc_gcp_altscontext_proto_msgTypes,
+	}.Build()
+	File_grpc_gcp_altscontext_proto = out.File
+	file_grpc_gcp_altscontext_proto_rawDesc = nil
+	file_grpc_gcp_altscontext_proto_goTypes = nil
+	file_grpc_gcp_altscontext_proto_depIdxs = nil
+}

vendor/google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp/handshaker_grpc.pb.go

@@ -0,0 +1,149 @@
+// Code generated by protoc-gen-go-grpc. DO NOT EDIT.
+// versions:
+// - protoc-gen-go-grpc v1.1.0
+// - protoc             v3.14.0
+// source: grpc/gcp/handshaker.proto
+
+package grpc_gcp
+
+import (
+	context "context"
+	grpc "google.golang.org/grpc"
+	codes "google.golang.org/grpc/codes"
+	status "google.golang.org/grpc/status"
+)
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+// Requires gRPC-Go v1.32.0 or later.
+const _ = grpc.SupportPackageIsVersion7
+
+// HandshakerServiceClient is the client API for HandshakerService service.
+//
+// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream.
+type HandshakerServiceClient interface {
+	// Handshaker service accepts a stream of handshaker request, returning a
+	// stream of handshaker response. Client is expected to send exactly one
+	// message with either client_start or server_start followed by one or more
+	// messages with next. Each time client sends a request, the handshaker
+	// service expects to respond. Client does not have to wait for service's
+	// response before sending next request.
+	DoHandshake(ctx context.Context, opts ...grpc.CallOption) (HandshakerService_DoHandshakeClient, error)
+}
+
+type handshakerServiceClient struct {
+	cc grpc.ClientConnInterface
+}
+
+func NewHandshakerServiceClient(cc grpc.ClientConnInterface) HandshakerServiceClient {
+	return &handshakerServiceClient{cc}
+}
+
+func (c *handshakerServiceClient) DoHandshake(ctx context.Context, opts ...grpc.CallOption) (HandshakerService_DoHandshakeClient, error) {
+	stream, err := c.cc.NewStream(ctx, &HandshakerService_ServiceDesc.Streams[0], "/grpc.gcp.HandshakerService/DoHandshake", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &handshakerServiceDoHandshakeClient{stream}
+	return x, nil
+}
+
+type HandshakerService_DoHandshakeClient interface {
+	Send(*HandshakerReq) error
+	Recv() (*HandshakerResp, error)
+	grpc.ClientStream
+}
+
+type handshakerServiceDoHandshakeClient struct {
+	grpc.ClientStream
+}
+
+func (x *handshakerServiceDoHandshakeClient) Send(m *HandshakerReq) error {
+	return x.ClientStream.SendMsg(m)
+}
+
+func (x *handshakerServiceDoHandshakeClient) Recv() (*HandshakerResp, error) {
+	m := new(HandshakerResp)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// HandshakerServiceServer is the server API for HandshakerService service.
+// All implementations must embed UnimplementedHandshakerServiceServer
+// for forward compatibility
+type HandshakerServiceServer interface {
+	// Handshaker service accepts a stream of handshaker request, returning a
+	// stream of handshaker response. Client is expected to send exactly one
+	// message with either client_start or server_start followed by one or more
+	// messages with next. Each time client sends a request, the handshaker
+	// service expects to respond. Client does not have to wait for service's
+	// response before sending next request.
+	DoHandshake(HandshakerService_DoHandshakeServer) error
+	mustEmbedUnimplementedHandshakerServiceServer()
+}
+
+// UnimplementedHandshakerServiceServer must be embedded to have forward compatible implementations.
+type UnimplementedHandshakerServiceServer struct {
+}
+
+func (UnimplementedHandshakerServiceServer) DoHandshake(HandshakerService_DoHandshakeServer) error {
+	return status.Errorf(codes.Unimplemented, "method DoHandshake not implemented")
+}
+func (UnimplementedHandshakerServiceServer) mustEmbedUnimplementedHandshakerServiceServer() {}
+
+// UnsafeHandshakerServiceServer may be embedded to opt out of forward compatibility for this service.
+// Use of this interface is not recommended, as added methods to HandshakerServiceServer will
+// result in compilation errors.
+type UnsafeHandshakerServiceServer interface {
+	mustEmbedUnimplementedHandshakerServiceServer()
+}
+
+func RegisterHandshakerServiceServer(s grpc.ServiceRegistrar, srv HandshakerServiceServer) {
+	s.RegisterService(&HandshakerService_ServiceDesc, srv)
+}
+
+func _HandshakerService_DoHandshake_Handler(srv interface{}, stream grpc.ServerStream) error {
+	return srv.(HandshakerServiceServer).DoHandshake(&handshakerServiceDoHandshakeServer{stream})
+}
+
+type HandshakerService_DoHandshakeServer interface {
+	Send(*HandshakerResp) error
+	Recv() (*HandshakerReq, error)
+	grpc.ServerStream
+}
+
+type handshakerServiceDoHandshakeServer struct {
+	grpc.ServerStream
+}
+
+func (x *handshakerServiceDoHandshakeServer) Send(m *HandshakerResp) error {
+	return x.ServerStream.SendMsg(m)
+}
+
+func (x *handshakerServiceDoHandshakeServer) Recv() (*HandshakerReq, error) {
+	m := new(HandshakerReq)
+	if err := x.ServerStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// HandshakerService_ServiceDesc is the grpc.ServiceDesc for HandshakerService service.
+// It's only intended for direct use with grpc.RegisterService,
+// and not to be introspected or modified (even as a copy)
+var HandshakerService_ServiceDesc = grpc.ServiceDesc{
+	ServiceName: "grpc.gcp.HandshakerService",
+	HandlerType: (*HandshakerServiceServer)(nil),
+	Methods:     []grpc.MethodDesc{},
+	Streams: []grpc.StreamDesc{
+		{
+			StreamName:    "DoHandshake",
+			Handler:       _HandshakerService_DoHandshake_Handler,
+			ServerStreams: true,
+			ClientStreams: true,
+		},
+	},
+	Metadata: "grpc/gcp/handshaker.proto",
+}

vendor/google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp/transport_security_common.pb.go

@@ -0,0 +1,326 @@
+// Copyright 2018 The gRPC Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// The canonical version of this proto can be found at
+// https://github.com/grpc/grpc-proto/blob/master/grpc/gcp/transport_security_common.proto
+
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.25.0
+// 	protoc        v3.14.0
+// source: grpc/gcp/transport_security_common.proto
+
+package grpc_gcp
+
+import (
+	proto "github.com/golang/protobuf/proto"
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+// This is a compile-time assertion that a sufficiently up-to-date version
+// of the legacy proto package is being used.
+const _ = proto.ProtoPackageIsVersion4
+
+// The security level of the created channel. The list is sorted in increasing
+// level of security. This order must always be maintained.
+type SecurityLevel int32
+
+const (
+	SecurityLevel_SECURITY_NONE         SecurityLevel = 0
+	SecurityLevel_INTEGRITY_ONLY        SecurityLevel = 1
+	SecurityLevel_INTEGRITY_AND_PRIVACY SecurityLevel = 2
+)
+
+// Enum value maps for SecurityLevel.
+var (
+	SecurityLevel_name = map[int32]string{
+		0: "SECURITY_NONE",
+		1: "INTEGRITY_ONLY",
+		2: "INTEGRITY_AND_PRIVACY",
+	}
+	SecurityLevel_value = map[string]int32{
+		"SECURITY_NONE":         0,
+		"INTEGRITY_ONLY":        1,
+		"INTEGRITY_AND_PRIVACY": 2,
+	}
+)
+
+func (x SecurityLevel) Enum() *SecurityLevel {
+	p := new(SecurityLevel)
+	*p = x
+	return p
+}
+
+func (x SecurityLevel) String() string {
+	return protoimpl.X.EnumStringOf(x.Descriptor(), protoreflect.EnumNumber(x))
+}
+
+func (SecurityLevel) Descriptor() protoreflect.EnumDescriptor {
+	return file_grpc_gcp_transport_security_common_proto_enumTypes[0].Descriptor()
+}
+
+func (SecurityLevel) Type() protoreflect.EnumType {
+	return &file_grpc_gcp_transport_security_common_proto_enumTypes[0]
+}
+
+func (x SecurityLevel) Number() protoreflect.EnumNumber {
+	return protoreflect.EnumNumber(x)
+}
+
+// Deprecated: Use SecurityLevel.Descriptor instead.
+func (SecurityLevel) EnumDescriptor() ([]byte, []int) {
+	return file_grpc_gcp_transport_security_common_proto_rawDescGZIP(), []int{0}
+}
+
+// Max and min supported RPC protocol versions.
+type RpcProtocolVersions struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// Maximum supported RPC version.
+	MaxRpcVersion *RpcProtocolVersions_Version `protobuf:"bytes,1,opt,name=max_rpc_version,json=maxRpcVersion,proto3" json:"max_rpc_version,omitempty"`
+	// Minimum supported RPC version.
+	MinRpcVersion *RpcProtocolVersions_Version `protobuf:"bytes,2,opt,name=min_rpc_version,json=minRpcVersion,proto3" json:"min_rpc_version,omitempty"`
+}
+
+func (x *RpcProtocolVersions) Reset() {
+	*x = RpcProtocolVersions{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_gcp_transport_security_common_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *RpcProtocolVersions) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*RpcProtocolVersions) ProtoMessage() {}
+
+func (x *RpcProtocolVersions) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_gcp_transport_security_common_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use RpcProtocolVersions.ProtoReflect.Descriptor instead.
+func (*RpcProtocolVersions) Descriptor() ([]byte, []int) {
+	return file_grpc_gcp_transport_security_common_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *RpcProtocolVersions) GetMaxRpcVersion() *RpcProtocolVersions_Version {
+	if x != nil {
+		return x.MaxRpcVersion
+	}
+	return nil
+}
+
+func (x *RpcProtocolVersions) GetMinRpcVersion() *RpcProtocolVersions_Version {
+	if x != nil {
+		return x.MinRpcVersion
+	}
+	return nil
+}
+
+// RPC version contains a major version and a minor version.
+type RpcProtocolVersions_Version struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	Major uint32 `protobuf:"varint,1,opt,name=major,proto3" json:"major,omitempty"`
+	Minor uint32 `protobuf:"varint,2,opt,name=minor,proto3" json:"minor,omitempty"`
+}
+
+func (x *RpcProtocolVersions_Version) Reset() {
+	*x = RpcProtocolVersions_Version{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_grpc_gcp_transport_security_common_proto_msgTypes[1]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *RpcProtocolVersions_Version) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*RpcProtocolVersions_Version) ProtoMessage() {}
+
+func (x *RpcProtocolVersions_Version) ProtoReflect() protoreflect.Message {
+	mi := &file_grpc_gcp_transport_security_common_proto_msgTypes[1]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use RpcProtocolVersions_Version.ProtoReflect.Descriptor instead.
+func (*RpcProtocolVersions_Version) Descriptor() ([]byte, []int) {
+	return file_grpc_gcp_transport_security_common_proto_rawDescGZIP(), []int{0, 0}
+}
+
+func (x *RpcProtocolVersions_Version) GetMajor() uint32 {
+	if x != nil {
+		return x.Major
+	}
+	return 0
+}
+
+func (x *RpcProtocolVersions_Version) GetMinor() uint32 {
+	if x != nil {
+		return x.Minor
+	}
+	return 0
+}
+
+var File_grpc_gcp_transport_security_common_proto protoreflect.FileDescriptor
+
+var file_grpc_gcp_transport_security_common_proto_rawDesc = []byte{
+	0x0a, 0x28, 0x67, 0x72, 0x70, 0x63, 0x2f, 0x67, 0x63, 0x70, 0x2f, 0x74, 0x72, 0x61, 0x6e, 0x73,
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+	0x72, 0x73, 0x69, 0x6f, 0x6e, 0x12, 0x14, 0x0a, 0x05, 0x6d, 0x61, 0x6a, 0x6f, 0x72, 0x18, 0x01,
+	0x20, 0x01, 0x28, 0x0d, 0x52, 0x05, 0x6d, 0x61, 0x6a, 0x6f, 0x72, 0x12, 0x14, 0x0a, 0x05, 0x6d,
+	0x69, 0x6e, 0x6f, 0x72, 0x18, 0x02, 0x20, 0x01, 0x28, 0x0d, 0x52, 0x05, 0x6d, 0x69, 0x6e, 0x6f,
+	0x72, 0x2a, 0x51, 0x0a, 0x0d, 0x53, 0x65, 0x63, 0x75, 0x72, 0x69, 0x74, 0x79, 0x4c, 0x65, 0x76,
+	0x65, 0x6c, 0x12, 0x11, 0x0a, 0x0d, 0x53, 0x45, 0x43, 0x55, 0x52, 0x49, 0x54, 0x59, 0x5f, 0x4e,
+	0x4f, 0x4e, 0x45, 0x10, 0x00, 0x12, 0x12, 0x0a, 0x0e, 0x49, 0x4e, 0x54, 0x45, 0x47, 0x52, 0x49,
+	0x54, 0x59, 0x5f, 0x4f, 0x4e, 0x4c, 0x59, 0x10, 0x01, 0x12, 0x19, 0x0a, 0x15, 0x49, 0x4e, 0x54,
+	0x45, 0x47, 0x52, 0x49, 0x54, 0x59, 0x5f, 0x41, 0x4e, 0x44, 0x5f, 0x50, 0x52, 0x49, 0x56, 0x41,
+	0x43, 0x59, 0x10, 0x02, 0x42, 0x78, 0x0a, 0x15, 0x69, 0x6f, 0x2e, 0x67, 0x72, 0x70, 0x63, 0x2e,
+	0x61, 0x6c, 0x74, 0x73, 0x2e, 0x69, 0x6e, 0x74, 0x65, 0x72, 0x6e, 0x61, 0x6c, 0x42, 0x1c, 0x54,
+	0x72, 0x61, 0x6e, 0x73, 0x70, 0x6f, 0x72, 0x74, 0x53, 0x65, 0x63, 0x75, 0x72, 0x69, 0x74, 0x79,
+	0x43, 0x6f, 0x6d, 0x6d, 0x6f, 0x6e, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01, 0x5a, 0x3f, 0x67,
+	0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61, 0x6e, 0x67, 0x2e, 0x6f, 0x72, 0x67,
+	0x2f, 0x67, 0x72, 0x70, 0x63, 0x2f, 0x63, 0x72, 0x65, 0x64, 0x65, 0x6e, 0x74, 0x69, 0x61, 0x6c,
+	0x73, 0x2f, 0x61, 0x6c, 0x74, 0x73, 0x2f, 0x69, 0x6e, 0x74, 0x65, 0x72, 0x6e, 0x61, 0x6c, 0x2f,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2f, 0x67, 0x72, 0x70, 0x63, 0x5f, 0x67, 0x63, 0x70, 0x62, 0x06,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_grpc_gcp_transport_security_common_proto_rawDescOnce sync.Once
+	file_grpc_gcp_transport_security_common_proto_rawDescData = file_grpc_gcp_transport_security_common_proto_rawDesc
+)
+
+func file_grpc_gcp_transport_security_common_proto_rawDescGZIP() []byte {
+	file_grpc_gcp_transport_security_common_proto_rawDescOnce.Do(func() {
+		file_grpc_gcp_transport_security_common_proto_rawDescData = protoimpl.X.CompressGZIP(file_grpc_gcp_transport_security_common_proto_rawDescData)
+	})
+	return file_grpc_gcp_transport_security_common_proto_rawDescData
+}
+
+var file_grpc_gcp_transport_security_common_proto_enumTypes = make([]protoimpl.EnumInfo, 1)
+var file_grpc_gcp_transport_security_common_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
+var file_grpc_gcp_transport_security_common_proto_goTypes = []interface{}{
+	(SecurityLevel)(0),                  // 0: grpc.gcp.SecurityLevel
+	(*RpcProtocolVersions)(nil),         // 1: grpc.gcp.RpcProtocolVersions
+	(*RpcProtocolVersions_Version)(nil), // 2: grpc.gcp.RpcProtocolVersions.Version
+}
+var file_grpc_gcp_transport_security_common_proto_depIdxs = []int32{
+	2, // 0: grpc.gcp.RpcProtocolVersions.max_rpc_version:type_name -> grpc.gcp.RpcProtocolVersions.Version
+	2, // 1: grpc.gcp.RpcProtocolVersions.min_rpc_version:type_name -> grpc.gcp.RpcProtocolVersions.Version
+	2, // [2:2] is the sub-list for method output_type
+	2, // [2:2] is the sub-list for method input_type
+	2, // [2:2] is the sub-list for extension type_name
+	2, // [2:2] is the sub-list for extension extendee
+	0, // [0:2] is the sub-list for field type_name
+}
+
+func init() { file_grpc_gcp_transport_security_common_proto_init() }
+func file_grpc_gcp_transport_security_common_proto_init() {
+	if File_grpc_gcp_transport_security_common_proto != nil {
+		return
+	}
+	if !protoimpl.UnsafeEnabled {
+		file_grpc_gcp_transport_security_common_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*RpcProtocolVersions); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_grpc_gcp_transport_security_common_proto_msgTypes[1].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*RpcProtocolVersions_Version); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_grpc_gcp_transport_security_common_proto_rawDesc,
+			NumEnums:      1,
+			NumMessages:   2,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_grpc_gcp_transport_security_common_proto_goTypes,
+		DependencyIndexes: file_grpc_gcp_transport_security_common_proto_depIdxs,
+		EnumInfos:         file_grpc_gcp_transport_security_common_proto_enumTypes,
+		MessageInfos:      file_grpc_gcp_transport_security_common_proto_msgTypes,
+	}.Build()
+	File_grpc_gcp_transport_security_common_proto = out.File
+	file_grpc_gcp_transport_security_common_proto_rawDesc = nil
+	file_grpc_gcp_transport_security_common_proto_goTypes = nil
+	file_grpc_gcp_transport_security_common_proto_depIdxs = nil
+}

vendor/google.golang.org/grpc/credentials/alts/utils.go

@@ -0,0 +1,70 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package alts
+
+import (
+	"context"
+	"errors"
+	"strings"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/status"
+)
+
+// AuthInfoFromContext extracts the alts.AuthInfo object from the given context,
+// if it exists. This API should be used by gRPC server RPC handlers to get
+// information about the communicating peer. For client-side, use grpc.Peer()
+// CallOption.
+func AuthInfoFromContext(ctx context.Context) (AuthInfo, error) {
+	p, ok := peer.FromContext(ctx)
+	if !ok {
+		return nil, errors.New("no Peer found in Context")
+	}
+	return AuthInfoFromPeer(p)
+}
+
+// AuthInfoFromPeer extracts the alts.AuthInfo object from the given peer, if it
+// exists. This API should be used by gRPC clients after obtaining a peer object
+// using the grpc.Peer() CallOption.
+func AuthInfoFromPeer(p *peer.Peer) (AuthInfo, error) {
+	altsAuthInfo, ok := p.AuthInfo.(AuthInfo)
+	if !ok {
+		return nil, errors.New("no alts.AuthInfo found in Peer")
+	}
+	return altsAuthInfo, nil
+}
+
+// ClientAuthorizationCheck checks whether the client is authorized to access
+// the requested resources based on the given expected client service accounts.
+// This API should be used by gRPC server RPC handlers. This API should not be
+// used by clients.
+func ClientAuthorizationCheck(ctx context.Context, expectedServiceAccounts []string) error {
+	authInfo, err := AuthInfoFromContext(ctx)
+	if err != nil {
+		return status.Errorf(codes.PermissionDenied, "The context is not an ALTS-compatible context: %v", err)
+	}
+	peer := authInfo.PeerServiceAccount()
+	for _, sa := range expectedServiceAccounts {
+		if strings.EqualFold(peer, sa) {
+			return nil
+		}
+	}
+	return status.Errorf(codes.PermissionDenied, "Client %v is not authorized", peer)
+}

vendor/google.golang.org/grpc/credentials/google/google.go

@@ -0,0 +1,136 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package google defines credentials for google cloud services.
+package google
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/credentials/alts"
+	"google.golang.org/grpc/credentials/oauth"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal"
+)
+
+const tokenRequestTimeout = 30 * time.Second
+
+var logger = grpclog.Component("credentials")
+
+// NewDefaultCredentials returns a credentials bundle that is configured to work
+// with google services.
+//
+// This API is experimental.
+func NewDefaultCredentials() credentials.Bundle {
+	c := &creds{
+		newPerRPCCreds: func() credentials.PerRPCCredentials {
+			ctx, cancel := context.WithTimeout(context.Background(), tokenRequestTimeout)
+			defer cancel()
+			perRPCCreds, err := oauth.NewApplicationDefault(ctx)
+			if err != nil {
+				logger.Warningf("google default creds: failed to create application oauth: %v", err)
+			}
+			return perRPCCreds
+		},
+	}
+	bundle, err := c.NewWithMode(internal.CredsBundleModeFallback)
+	if err != nil {
+		logger.Warningf("google default creds: failed to create new creds: %v", err)
+	}
+	return bundle
+}
+
+// NewComputeEngineCredentials returns a credentials bundle that is configured to work
+// with google services. This API must only be used when running on GCE. Authentication configured
+// by this API represents the GCE VM's default service account.
+//
+// This API is experimental.
+func NewComputeEngineCredentials() credentials.Bundle {
+	c := &creds{
+		newPerRPCCreds: func() credentials.PerRPCCredentials {
+			return oauth.NewComputeEngine()
+		},
+	}
+	bundle, err := c.NewWithMode(internal.CredsBundleModeFallback)
+	if err != nil {
+		logger.Warningf("compute engine creds: failed to create new creds: %v", err)
+	}
+	return bundle
+}
+
+// creds implements credentials.Bundle.
+type creds struct {
+	// Supported modes are defined in internal/internal.go.
+	mode string
+	// The transport credentials associated with this bundle.
+	transportCreds credentials.TransportCredentials
+	// The per RPC credentials associated with this bundle.
+	perRPCCreds credentials.PerRPCCredentials
+	// Creates new per RPC credentials
+	newPerRPCCreds func() credentials.PerRPCCredentials
+}
+
+func (c *creds) TransportCredentials() credentials.TransportCredentials {
+	return c.transportCreds
+}
+
+func (c *creds) PerRPCCredentials() credentials.PerRPCCredentials {
+	if c == nil {
+		return nil
+	}
+	return c.perRPCCreds
+}
+
+var (
+	newTLS = func() credentials.TransportCredentials {
+		return credentials.NewTLS(nil)
+	}
+	newALTS = func() credentials.TransportCredentials {
+		return alts.NewClientCreds(alts.DefaultClientOptions())
+	}
+)
+
+// NewWithMode should make a copy of Bundle, and switch mode. Modifying the
+// existing Bundle may cause races.
+func (c *creds) NewWithMode(mode string) (credentials.Bundle, error) {
+	newCreds := &creds{
+		mode:           mode,
+		newPerRPCCreds: c.newPerRPCCreds,
+	}
+
+	// Create transport credentials.
+	switch mode {
+	case internal.CredsBundleModeFallback:
+		newCreds.transportCreds = newClusterTransportCreds(newTLS(), newALTS())
+	case internal.CredsBundleModeBackendFromBalancer, internal.CredsBundleModeBalancer:
+		// Only the clients can use google default credentials, so we only need
+		// to create new ALTS client creds here.
+		newCreds.transportCreds = newALTS()
+	default:
+		return nil, fmt.Errorf("unsupported mode: %v", mode)
+	}
+
+	if mode == internal.CredsBundleModeFallback || mode == internal.CredsBundleModeBackendFromBalancer {
+		newCreds.perRPCCreds = newCreds.newPerRPCCreds()
+	}
+
+	return newCreds, nil
+}

vendor/google.golang.org/grpc/credentials/google/xds.go

@@ -0,0 +1,90 @@
+/*
+ *
+ * Copyright 2021 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package google
+
+import (
+	"context"
+	"net"
+
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/internal"
+)
+
+const cfeClusterName = "google-cfe"
+
+// clusterTransportCreds is a combo of TLS + ALTS.
+//
+// On the client, ClientHandshake picks TLS or ALTS based on address attributes.
+// - if attributes has cluster name
+//   - if cluster name is "google_cfe", use TLS
+//   - otherwise, use ALTS
+// - else, do TLS
+//
+// On the server, ServerHandshake always does TLS.
+type clusterTransportCreds struct {
+	tls  credentials.TransportCredentials
+	alts credentials.TransportCredentials
+}
+
+func newClusterTransportCreds(tls, alts credentials.TransportCredentials) *clusterTransportCreds {
+	return &clusterTransportCreds{
+		tls:  tls,
+		alts: alts,
+	}
+}
+
+func (c *clusterTransportCreds) ClientHandshake(ctx context.Context, authority string, rawConn net.Conn) (net.Conn, credentials.AuthInfo, error) {
+	chi := credentials.ClientHandshakeInfoFromContext(ctx)
+	if chi.Attributes == nil {
+		return c.tls.ClientHandshake(ctx, authority, rawConn)
+	}
+	cn, ok := internal.GetXDSHandshakeClusterName(chi.Attributes)
+	if !ok || cn == cfeClusterName {
+		return c.tls.ClientHandshake(ctx, authority, rawConn)
+	}
+	// If attributes have cluster name, and cluster name is not cfe, it's a
+	// backend address, use ALTS.
+	return c.alts.ClientHandshake(ctx, authority, rawConn)
+}
+
+func (c *clusterTransportCreds) ServerHandshake(conn net.Conn) (net.Conn, credentials.AuthInfo, error) {
+	return c.tls.ServerHandshake(conn)
+}
+
+func (c *clusterTransportCreds) Info() credentials.ProtocolInfo {
+	// TODO: this always returns tls.Info now, because we don't have a cluster
+	// name to check when this method is called. This method doesn't affect
+	// anything important now. We may want to revisit this if it becomes more
+	// important later.
+	return c.tls.Info()
+}
+
+func (c *clusterTransportCreds) Clone() credentials.TransportCredentials {
+	return &clusterTransportCreds{
+		tls:  c.tls.Clone(),
+		alts: c.alts.Clone(),
+	}
+}
+
+func (c *clusterTransportCreds) OverrideServerName(s string) error {
+	if err := c.tls.OverrideServerName(s); err != nil {
+		return err
+	}
+	return c.alts.OverrideServerName(s)
+}

vendor/google.golang.org/grpc/credentials/oauth/oauth.go

@@ -0,0 +1,225 @@
+/*
+ *
+ * Copyright 2015 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package oauth implements gRPC credentials using OAuth.
+package oauth
+
+import (
+	"context"
+	"fmt"
+	"io/ioutil"
+	"sync"
+
+	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/google"
+	"golang.org/x/oauth2/jwt"
+	"google.golang.org/grpc/credentials"
+)
+
+// TokenSource supplies PerRPCCredentials from an oauth2.TokenSource.
+type TokenSource struct {
+	oauth2.TokenSource
+}
+
+// GetRequestMetadata gets the request metadata as a map from a TokenSource.
+func (ts TokenSource) GetRequestMetadata(ctx context.Context, uri ...string) (map[string]string, error) {
+	token, err := ts.Token()
+	if err != nil {
+		return nil, err
+	}
+	ri, _ := credentials.RequestInfoFromContext(ctx)
+	if err = credentials.CheckSecurityLevel(ri.AuthInfo, credentials.PrivacyAndIntegrity); err != nil {
+		return nil, fmt.Errorf("unable to transfer TokenSource PerRPCCredentials: %v", err)
+	}
+	return map[string]string{
+		"authorization": token.Type() + " " + token.AccessToken,
+	}, nil
+}
+
+// RequireTransportSecurity indicates whether the credentials requires transport security.
+func (ts TokenSource) RequireTransportSecurity() bool {
+	return true
+}
+
+type jwtAccess struct {
+	jsonKey []byte
+}
+
+// NewJWTAccessFromFile creates PerRPCCredentials from the given keyFile.
+func NewJWTAccessFromFile(keyFile string) (credentials.PerRPCCredentials, error) {
+	jsonKey, err := ioutil.ReadFile(keyFile)
+	if err != nil {
+		return nil, fmt.Errorf("credentials: failed to read the service account key file: %v", err)
+	}
+	return NewJWTAccessFromKey(jsonKey)
+}
+
+// NewJWTAccessFromKey creates PerRPCCredentials from the given jsonKey.
+func NewJWTAccessFromKey(jsonKey []byte) (credentials.PerRPCCredentials, error) {
+	return jwtAccess{jsonKey}, nil
+}
+
+func (j jwtAccess) GetRequestMetadata(ctx context.Context, uri ...string) (map[string]string, error) {
+	// TODO: the returned TokenSource is reusable. Store it in a sync.Map, with
+	// uri as the key, to avoid recreating for every RPC.
+	ts, err := google.JWTAccessTokenSourceFromJSON(j.jsonKey, uri[0])
+	if err != nil {
+		return nil, err
+	}
+	token, err := ts.Token()
+	if err != nil {
+		return nil, err
+	}
+	ri, _ := credentials.RequestInfoFromContext(ctx)
+	if err = credentials.CheckSecurityLevel(ri.AuthInfo, credentials.PrivacyAndIntegrity); err != nil {
+		return nil, fmt.Errorf("unable to transfer jwtAccess PerRPCCredentials: %v", err)
+	}
+	return map[string]string{
+		"authorization": token.Type() + " " + token.AccessToken,
+	}, nil
+}
+
+func (j jwtAccess) RequireTransportSecurity() bool {
+	return true
+}
+
+// oauthAccess supplies PerRPCCredentials from a given token.
+type oauthAccess struct {
+	token oauth2.Token
+}
+
+// NewOauthAccess constructs the PerRPCCredentials using a given token.
+func NewOauthAccess(token *oauth2.Token) credentials.PerRPCCredentials {
+	return oauthAccess{token: *token}
+}
+
+func (oa oauthAccess) GetRequestMetadata(ctx context.Context, uri ...string) (map[string]string, error) {
+	ri, _ := credentials.RequestInfoFromContext(ctx)
+	if err := credentials.CheckSecurityLevel(ri.AuthInfo, credentials.PrivacyAndIntegrity); err != nil {
+		return nil, fmt.Errorf("unable to transfer oauthAccess PerRPCCredentials: %v", err)
+	}
+	return map[string]string{
+		"authorization": oa.token.Type() + " " + oa.token.AccessToken,
+	}, nil
+}
+
+func (oa oauthAccess) RequireTransportSecurity() bool {
+	return true
+}
+
+// NewComputeEngine constructs the PerRPCCredentials that fetches access tokens from
+// Google Compute Engine (GCE)'s metadata server. It is only valid to use this
+// if your program is running on a GCE instance.
+// TODO(dsymonds): Deprecate and remove this.
+func NewComputeEngine() credentials.PerRPCCredentials {
+	return TokenSource{google.ComputeTokenSource("")}
+}
+
+// serviceAccount represents PerRPCCredentials via JWT signing key.
+type serviceAccount struct {
+	mu     sync.Mutex
+	config *jwt.Config
+	t      *oauth2.Token
+}
+
+func (s *serviceAccount) GetRequestMetadata(ctx context.Context, uri ...string) (map[string]string, error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.t.Valid() {
+		var err error
+		s.t, err = s.config.TokenSource(ctx).Token()
+		if err != nil {
+			return nil, err
+		}
+	}
+	ri, _ := credentials.RequestInfoFromContext(ctx)
+	if err := credentials.CheckSecurityLevel(ri.AuthInfo, credentials.PrivacyAndIntegrity); err != nil {
+		return nil, fmt.Errorf("unable to transfer serviceAccount PerRPCCredentials: %v", err)
+	}
+	return map[string]string{
+		"authorization": s.t.Type() + " " + s.t.AccessToken,
+	}, nil
+}
+
+func (s *serviceAccount) RequireTransportSecurity() bool {
+	return true
+}
+
+// NewServiceAccountFromKey constructs the PerRPCCredentials using the JSON key slice
+// from a Google Developers service account.
+func NewServiceAccountFromKey(jsonKey []byte, scope ...string) (credentials.PerRPCCredentials, error) {
+	config, err := google.JWTConfigFromJSON(jsonKey, scope...)
+	if err != nil {
+		return nil, err
+	}
+	return &serviceAccount{config: config}, nil
+}
+
+// NewServiceAccountFromFile constructs the PerRPCCredentials using the JSON key file
+// of a Google Developers service account.
+func NewServiceAccountFromFile(keyFile string, scope ...string) (credentials.PerRPCCredentials, error) {
+	jsonKey, err := ioutil.ReadFile(keyFile)
+	if err != nil {
+		return nil, fmt.Errorf("credentials: failed to read the service account key file: %v", err)
+	}
+	return NewServiceAccountFromKey(jsonKey, scope...)
+}
+
+// NewApplicationDefault returns "Application Default Credentials". For more
+// detail, see https://developers.google.com/accounts/docs/application-default-credentials.
+func NewApplicationDefault(ctx context.Context, scope ...string) (credentials.PerRPCCredentials, error) {
+	creds, err := google.FindDefaultCredentials(ctx, scope...)
+	if err != nil {
+		return nil, err
+	}
+
+	// If JSON is nil, the authentication is provided by the environment and not
+	// with a credentials file, e.g. when code is running on Google Cloud
+	// Platform. Use the returned token source.
+	if creds.JSON == nil {
+		return TokenSource{creds.TokenSource}, nil
+	}
+
+	// If auth is provided by env variable or creds file, the behavior will be
+	// different based on whether scope is set. Because the returned
+	// creds.TokenSource does oauth with jwt by default, and it requires scope.
+	// We can only use it if scope is not empty, otherwise it will fail with
+	// missing scope error.
+	//
+	// If scope is set, use it, it should just work.
+	//
+	// If scope is not set, we try to use jwt directly without oauth (this only
+	// works if it's a service account).
+
+	if len(scope) != 0 {
+		return TokenSource{creds.TokenSource}, nil
+	}
+
+	// Try to convert JSON to a jwt config without setting the optional scope
+	// parameter to check if it's a service account (the function errors if it's
+	// not). This is necessary because the returned config doesn't show the type
+	// of the account.
+	if _, err := google.JWTConfigFromJSON(creds.JSON); err != nil {
+		// If this fails, it's not a service account, return the original
+		// TokenSource from above.
+		return TokenSource{creds.TokenSource}, nil
+	}
+
+	// If it's a service account, create a JWT only access with the key.
+	return NewJWTAccessFromKey(creds.JSON)
+}

vendor/google.golang.org/grpc/internal/googlecloud/googlecloud.go

@@ -0,0 +1,128 @@
+/*
+ *
+ * Copyright 2021 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package googlecloud contains internal helpful functions for google cloud.
+package googlecloud
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"regexp"
+	"runtime"
+	"strings"
+	"sync"
+
+	"google.golang.org/grpc/grpclog"
+	internalgrpclog "google.golang.org/grpc/internal/grpclog"
+)
+
+const (
+	linuxProductNameFile     = "/sys/class/dmi/id/product_name"
+	windowsCheckCommand      = "powershell.exe"
+	windowsCheckCommandArgs  = "Get-WmiObject -Class Win32_BIOS"
+	powershellOutputFilter   = "Manufacturer"
+	windowsManufacturerRegex = ":(.*)"
+
+	logPrefix = "[googlecloud]"
+)
+
+var (
+	// The following two variables will be reassigned in tests.
+	runningOS          = runtime.GOOS
+	manufacturerReader = func() (io.Reader, error) {
+		switch runningOS {
+		case "linux":
+			return os.Open(linuxProductNameFile)
+		case "windows":
+			cmd := exec.Command(windowsCheckCommand, windowsCheckCommandArgs)
+			out, err := cmd.Output()
+			if err != nil {
+				return nil, err
+			}
+			for _, line := range strings.Split(strings.TrimSuffix(string(out), "\n"), "\n") {
+				if strings.HasPrefix(line, powershellOutputFilter) {
+					re := regexp.MustCompile(windowsManufacturerRegex)
+					name := re.FindString(line)
+					name = strings.TrimLeft(name, ":")
+					return strings.NewReader(name), nil
+				}
+			}
+			return nil, errors.New("cannot determine the machine's manufacturer")
+		default:
+			return nil, fmt.Errorf("%s is not supported", runningOS)
+		}
+	}
+
+	vmOnGCEOnce sync.Once
+	vmOnGCE     bool
+
+	logger = internalgrpclog.NewPrefixLogger(grpclog.Component("googlecloud"), logPrefix)
+)
+
+// OnGCE returns whether the client is running on GCE.
+//
+// It provides similar functionality as metadata.OnGCE from the cloud library
+// package. We keep this to avoid depending on the cloud library module.
+func OnGCE() bool {
+	vmOnGCEOnce.Do(func() {
+		vmOnGCE = isRunningOnGCE()
+	})
+	return vmOnGCE
+}
+
+// isRunningOnGCE checks whether the local system, without doing a network request is
+// running on GCP.
+func isRunningOnGCE() bool {
+	manufacturer, err := readManufacturer()
+	if err != nil {
+		logger.Infof("failed to read manufacturer %v, returning OnGCE=false", err)
+		return false
+	}
+	name := string(manufacturer)
+	switch runningOS {
+	case "linux":
+		name = strings.TrimSpace(name)
+		return name == "Google" || name == "Google Compute Engine"
+	case "windows":
+		name = strings.Replace(name, " ", "", -1)
+		name = strings.Replace(name, "\n", "", -1)
+		name = strings.Replace(name, "\r", "", -1)
+		return name == "Google"
+	default:
+		return false
+	}
+}
+
+func readManufacturer() ([]byte, error) {
+	reader, err := manufacturerReader()
+	if err != nil {
+		return nil, err
+	}
+	if reader == nil {
+		return nil, errors.New("got nil reader")
+	}
+	manufacturer, err := ioutil.ReadAll(reader)
+	if err != nil {
+		return nil, fmt.Errorf("failed reading %v: %v", linuxProductNameFile, err)
+	}
+	return manufacturer, nil
+}

vendor/google.golang.org/protobuf/types/known/emptypb/empty.pb.go

@@ -0,0 +1,168 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: google/protobuf/empty.proto
+
+package emptypb
+
+import (
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+)
+
+// A generic empty message that you can re-use to avoid defining duplicated
+// empty messages in your APIs. A typical example is to use it as the request
+// or the response type of an API method. For instance:
+//
+//     service Foo {
+//       rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);
+//     }
+//
+// The JSON representation for `Empty` is empty JSON object `{}`.
+type Empty struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+}
+
+func (x *Empty) Reset() {
+	*x = Empty{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_google_protobuf_empty_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *Empty) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Empty) ProtoMessage() {}
+
+func (x *Empty) ProtoReflect() protoreflect.Message {
+	mi := &file_google_protobuf_empty_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use Empty.ProtoReflect.Descriptor instead.
+func (*Empty) Descriptor() ([]byte, []int) {
+	return file_google_protobuf_empty_proto_rawDescGZIP(), []int{0}
+}
+
+var File_google_protobuf_empty_proto protoreflect.FileDescriptor
+
+var file_google_protobuf_empty_proto_rawDesc = []byte{
+	0x0a, 0x1b, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75,
+	0x66, 0x2f, 0x65, 0x6d, 0x70, 0x74, 0x79, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x0f, 0x67,
+	0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x22, 0x07,
+	0x0a, 0x05, 0x45, 0x6d, 0x70, 0x74, 0x79, 0x42, 0x7d, 0x0a, 0x13, 0x63, 0x6f, 0x6d, 0x2e, 0x67,
+	0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x42, 0x0a,
+	0x45, 0x6d, 0x70, 0x74, 0x79, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01, 0x5a, 0x2e, 0x67, 0x6f,
+	0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61, 0x6e, 0x67, 0x2e, 0x6f, 0x72, 0x67, 0x2f,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2f, 0x74, 0x79, 0x70, 0x65, 0x73, 0x2f, 0x6b,
+	0x6e, 0x6f, 0x77, 0x6e, 0x2f, 0x65, 0x6d, 0x70, 0x74, 0x79, 0x70, 0x62, 0xf8, 0x01, 0x01, 0xa2,
+	0x02, 0x03, 0x47, 0x50, 0x42, 0xaa, 0x02, 0x1e, 0x47, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x50,
+	0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x57, 0x65, 0x6c, 0x6c, 0x4b, 0x6e, 0x6f, 0x77,
+	0x6e, 0x54, 0x79, 0x70, 0x65, 0x73, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_google_protobuf_empty_proto_rawDescOnce sync.Once
+	file_google_protobuf_empty_proto_rawDescData = file_google_protobuf_empty_proto_rawDesc
+)
+
+func file_google_protobuf_empty_proto_rawDescGZIP() []byte {
+	file_google_protobuf_empty_proto_rawDescOnce.Do(func() {
+		file_google_protobuf_empty_proto_rawDescData = protoimpl.X.CompressGZIP(file_google_protobuf_empty_proto_rawDescData)
+	})
+	return file_google_protobuf_empty_proto_rawDescData
+}
+
+var file_google_protobuf_empty_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
+var file_google_protobuf_empty_proto_goTypes = []interface{}{
+	(*Empty)(nil), // 0: google.protobuf.Empty
+}
+var file_google_protobuf_empty_proto_depIdxs = []int32{
+	0, // [0:0] is the sub-list for method output_type
+	0, // [0:0] is the sub-list for method input_type
+	0, // [0:0] is the sub-list for extension type_name
+	0, // [0:0] is the sub-list for extension extendee
+	0, // [0:0] is the sub-list for field type_name
+}
+
+func init() { file_google_protobuf_empty_proto_init() }
+func file_google_protobuf_empty_proto_init() {
+	if File_google_protobuf_empty_proto != nil {
+		return
+	}
+	if !protoimpl.UnsafeEnabled {
+		file_google_protobuf_empty_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*Empty); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_google_protobuf_empty_proto_rawDesc,
+			NumEnums:      0,
+			NumMessages:   1,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_google_protobuf_empty_proto_goTypes,
+		DependencyIndexes: file_google_protobuf_empty_proto_depIdxs,
+		MessageInfos:      file_google_protobuf_empty_proto_msgTypes,
+	}.Build()
+	File_google_protobuf_empty_proto = out.File
+	file_google_protobuf_empty_proto_rawDesc = nil
+	file_google_protobuf_empty_proto_goTypes = nil
+	file_google_protobuf_empty_proto_depIdxs = nil
+}

vendor/google.golang.org/protobuf/types/known/fieldmaskpb/field_mask.pb.go

@@ -0,0 +1,591 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: google/protobuf/field_mask.proto
+
+// Package fieldmaskpb contains generated types for google/protobuf/field_mask.proto.
+//
+// The FieldMask message represents a set of symbolic field paths.
+// The paths are specific to some target message type,
+// which is not stored within the FieldMask message itself.
+//
+//
+// Constructing a FieldMask
+//
+// The New function is used construct a FieldMask:
+//
+//	var messageType *descriptorpb.DescriptorProto
+//	fm, err := fieldmaskpb.New(messageType, "field.name", "field.number")
+//	if err != nil {
+//		... // handle error
+//	}
+//	... // make use of fm
+//
+// The "field.name" and "field.number" paths are valid paths according to the
+// google.protobuf.DescriptorProto message. Use of a path that does not correlate
+// to valid fields reachable from DescriptorProto would result in an error.
+//
+// Once a FieldMask message has been constructed,
+// the Append method can be used to insert additional paths to the path set:
+//
+//	var messageType *descriptorpb.DescriptorProto
+//	if err := fm.Append(messageType, "options"); err != nil {
+//		... // handle error
+//	}
+//
+//
+// Type checking a FieldMask
+//
+// In order to verify that a FieldMask represents a set of fields that are
+// reachable from some target message type, use the IsValid method:
+//
+//	var messageType *descriptorpb.DescriptorProto
+//	if fm.IsValid(messageType) {
+//		... // make use of fm
+//	}
+//
+// IsValid needs to be passed the target message type as an input since the
+// FieldMask message itself does not store the message type that the set of paths
+// are for.
+package fieldmaskpb
+
+import (
+	proto "google.golang.org/protobuf/proto"
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sort "sort"
+	strings "strings"
+	sync "sync"
+)
+
+// `FieldMask` represents a set of symbolic field paths, for example:
+//
+//     paths: "f.a"
+//     paths: "f.b.d"
+//
+// Here `f` represents a field in some root message, `a` and `b`
+// fields in the message found in `f`, and `d` a field found in the
+// message in `f.b`.
+//
+// Field masks are used to specify a subset of fields that should be
+// returned by a get operation or modified by an update operation.
+// Field masks also have a custom JSON encoding (see below).
+//
+// # Field Masks in Projections
+//
+// When used in the context of a projection, a response message or
+// sub-message is filtered by the API to only contain those fields as
+// specified in the mask. For example, if the mask in the previous
+// example is applied to a response message as follows:
+//
+//     f {
+//       a : 22
+//       b {
+//         d : 1
+//         x : 2
+//       }
+//       y : 13
+//     }
+//     z: 8
+//
+// The result will not contain specific values for fields x,y and z
+// (their value will be set to the default, and omitted in proto text
+// output):
+//
+//
+//     f {
+//       a : 22
+//       b {
+//         d : 1
+//       }
+//     }
+//
+// A repeated field is not allowed except at the last position of a
+// paths string.
+//
+// If a FieldMask object is not present in a get operation, the
+// operation applies to all fields (as if a FieldMask of all fields
+// had been specified).
+//
+// Note that a field mask does not necessarily apply to the
+// top-level response message. In case of a REST get operation, the
+// field mask applies directly to the response, but in case of a REST
+// list operation, the mask instead applies to each individual message
+// in the returned resource list. In case of a REST custom method,
+// other definitions may be used. Where the mask applies will be
+// clearly documented together with its declaration in the API.  In
+// any case, the effect on the returned resource/resources is required
+// behavior for APIs.
+//
+// # Field Masks in Update Operations
+//
+// A field mask in update operations specifies which fields of the
+// targeted resource are going to be updated. The API is required
+// to only change the values of the fields as specified in the mask
+// and leave the others untouched. If a resource is passed in to
+// describe the updated values, the API ignores the values of all
+// fields not covered by the mask.
+//
+// If a repeated field is specified for an update operation, new values will
+// be appended to the existing repeated field in the target resource. Note that
+// a repeated field is only allowed in the last position of a `paths` string.
+//
+// If a sub-message is specified in the last position of the field mask for an
+// update operation, then new value will be merged into the existing sub-message
+// in the target resource.
+//
+// For example, given the target message:
+//
+//     f {
+//       b {
+//         d: 1
+//         x: 2
+//       }
+//       c: [1]
+//     }
+//
+// And an update message:
+//
+//     f {
+//       b {
+//         d: 10
+//       }
+//       c: [2]
+//     }
+//
+// then if the field mask is:
+//
+//  paths: ["f.b", "f.c"]
+//
+// then the result will be:
+//
+//     f {
+//       b {
+//         d: 10
+//         x: 2
+//       }
+//       c: [1, 2]
+//     }
+//
+// An implementation may provide options to override this default behavior for
+// repeated and message fields.
+//
+// In order to reset a field's value to the default, the field must
+// be in the mask and set to the default value in the provided resource.
+// Hence, in order to reset all fields of a resource, provide a default
+// instance of the resource and set all fields in the mask, or do
+// not provide a mask as described below.
+//
+// If a field mask is not present on update, the operation applies to
+// all fields (as if a field mask of all fields has been specified).
+// Note that in the presence of schema evolution, this may mean that
+// fields the client does not know and has therefore not filled into
+// the request will be reset to their default. If this is unwanted
+// behavior, a specific service may require a client to always specify
+// a field mask, producing an error if not.
+//
+// As with get operations, the location of the resource which
+// describes the updated values in the request message depends on the
+// operation kind. In any case, the effect of the field mask is
+// required to be honored by the API.
+//
+// ## Considerations for HTTP REST
+//
+// The HTTP kind of an update operation which uses a field mask must
+// be set to PATCH instead of PUT in order to satisfy HTTP semantics
+// (PUT must only be used for full updates).
+//
+// # JSON Encoding of Field Masks
+//
+// In JSON, a field mask is encoded as a single string where paths are
+// separated by a comma. Fields name in each path are converted
+// to/from lower-camel naming conventions.
+//
+// As an example, consider the following message declarations:
+//
+//     message Profile {
+//       User user = 1;
+//       Photo photo = 2;
+//     }
+//     message User {
+//       string display_name = 1;
+//       string address = 2;
+//     }
+//
+// In proto a field mask for `Profile` may look as such:
+//
+//     mask {
+//       paths: "user.display_name"
+//       paths: "photo"
+//     }
+//
+// In JSON, the same mask is represented as below:
+//
+//     {
+//       mask: "user.displayName,photo"
+//     }
+//
+// # Field Masks and Oneof Fields
+//
+// Field masks treat fields in oneofs just as regular fields. Consider the
+// following message:
+//
+//     message SampleMessage {
+//       oneof test_oneof {
+//         string name = 4;
+//         SubMessage sub_message = 9;
+//       }
+//     }
+//
+// The field mask can be:
+//
+//     mask {
+//       paths: "name"
+//     }
+//
+// Or:
+//
+//     mask {
+//       paths: "sub_message"
+//     }
+//
+// Note that oneof type names ("test_oneof" in this case) cannot be used in
+// paths.
+//
+// ## Field Mask Verification
+//
+// The implementation of any API method which has a FieldMask type field in the
+// request should verify the included field paths, and return an
+// `INVALID_ARGUMENT` error if any path is unmappable.
+type FieldMask struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// The set of field mask paths.
+	Paths []string `protobuf:"bytes,1,rep,name=paths,proto3" json:"paths,omitempty"`
+}
+
+// New constructs a field mask from a list of paths and verifies that
+// each one is valid according to the specified message type.
+func New(m proto.Message, paths ...string) (*FieldMask, error) {
+	x := new(FieldMask)
+	return x, x.Append(m, paths...)
+}
+
+// Union returns the union of all the paths in the input field masks.
+func Union(mx *FieldMask, my *FieldMask, ms ...*FieldMask) *FieldMask {
+	var out []string
+	out = append(out, mx.GetPaths()...)
+	out = append(out, my.GetPaths()...)
+	for _, m := range ms {
+		out = append(out, m.GetPaths()...)
+	}
+	return &FieldMask{Paths: normalizePaths(out)}
+}
+
+// Intersect returns the intersection of all the paths in the input field masks.
+func Intersect(mx *FieldMask, my *FieldMask, ms ...*FieldMask) *FieldMask {
+	var ss1, ss2 []string // reused buffers for performance
+	intersect := func(out, in []string) []string {
+		ss1 = normalizePaths(append(ss1[:0], in...))
+		ss2 = normalizePaths(append(ss2[:0], out...))
+		out = out[:0]
+		for i1, i2 := 0, 0; i1 < len(ss1) && i2 < len(ss2); {
+			switch s1, s2 := ss1[i1], ss2[i2]; {
+			case hasPathPrefix(s1, s2):
+				out = append(out, s1)
+				i1++
+			case hasPathPrefix(s2, s1):
+				out = append(out, s2)
+				i2++
+			case lessPath(s1, s2):
+				i1++
+			case lessPath(s2, s1):
+				i2++
+			}
+		}
+		return out
+	}
+
+	out := Union(mx, my, ms...).GetPaths()
+	out = intersect(out, mx.GetPaths())
+	out = intersect(out, my.GetPaths())
+	for _, m := range ms {
+		out = intersect(out, m.GetPaths())
+	}
+	return &FieldMask{Paths: normalizePaths(out)}
+}
+
+// IsValid reports whether all the paths are syntactically valid and
+// refer to known fields in the specified message type.
+// It reports false for a nil FieldMask.
+func (x *FieldMask) IsValid(m proto.Message) bool {
+	paths := x.GetPaths()
+	return x != nil && numValidPaths(m, paths) == len(paths)
+}
+
+// Append appends a list of paths to the mask and verifies that each one
+// is valid according to the specified message type.
+// An invalid path is not appended and breaks insertion of subsequent paths.
+func (x *FieldMask) Append(m proto.Message, paths ...string) error {
+	numValid := numValidPaths(m, paths)
+	x.Paths = append(x.Paths, paths[:numValid]...)
+	paths = paths[numValid:]
+	if len(paths) > 0 {
+		name := m.ProtoReflect().Descriptor().FullName()
+		return protoimpl.X.NewError("invalid path %q for message %q", paths[0], name)
+	}
+	return nil
+}
+
+func numValidPaths(m proto.Message, paths []string) int {
+	md0 := m.ProtoReflect().Descriptor()
+	for i, path := range paths {
+		md := md0
+		if !rangeFields(path, func(field string) bool {
+			// Search the field within the message.
+			if md == nil {
+				return false // not within a message
+			}
+			fd := md.Fields().ByName(protoreflect.Name(field))
+			// The real field name of a group is the message name.
+			if fd == nil {
+				gd := md.Fields().ByName(protoreflect.Name(strings.ToLower(field)))
+				if gd != nil && gd.Kind() == protoreflect.GroupKind && string(gd.Message().Name()) == field {
+					fd = gd
+				}
+			} else if fd.Kind() == protoreflect.GroupKind && string(fd.Message().Name()) != field {
+				fd = nil
+			}
+			if fd == nil {
+				return false // message has does not have this field
+			}
+
+			// Identify the next message to search within.
+			md = fd.Message() // may be nil
+
+			// Repeated fields are only allowed at the last postion.
+			if fd.IsList() || fd.IsMap() {
+				md = nil
+			}
+
+			return true
+		}) {
+			return i
+		}
+	}
+	return len(paths)
+}
+
+// Normalize converts the mask to its canonical form where all paths are sorted
+// and redundant paths are removed.
+func (x *FieldMask) Normalize() {
+	x.Paths = normalizePaths(x.Paths)
+}
+
+func normalizePaths(paths []string) []string {
+	sort.Slice(paths, func(i, j int) bool {
+		return lessPath(paths[i], paths[j])
+	})
+
+	// Elide any path that is a prefix match on the previous.
+	out := paths[:0]
+	for _, path := range paths {
+		if len(out) > 0 && hasPathPrefix(path, out[len(out)-1]) {
+			continue
+		}
+		out = append(out, path)
+	}
+	return out
+}
+
+// hasPathPrefix is like strings.HasPrefix, but further checks for either
+// an exact matche or that the prefix is delimited by a dot.
+func hasPathPrefix(path, prefix string) bool {
+	return strings.HasPrefix(path, prefix) && (len(path) == len(prefix) || path[len(prefix)] == '.')
+}
+
+// lessPath is a lexicographical comparison where dot is specially treated
+// as the smallest symbol.
+func lessPath(x, y string) bool {
+	for i := 0; i < len(x) && i < len(y); i++ {
+		if x[i] != y[i] {
+			return (x[i] - '.') < (y[i] - '.')
+		}
+	}
+	return len(x) < len(y)
+}
+
+// rangeFields is like strings.Split(path, "."), but avoids allocations by
+// iterating over each field in place and calling a iterator function.
+func rangeFields(path string, f func(field string) bool) bool {
+	for {
+		var field string
+		if i := strings.IndexByte(path, '.'); i >= 0 {
+			field, path = path[:i], path[i:]
+		} else {
+			field, path = path, ""
+		}
+
+		if !f(field) {
+			return false
+		}
+
+		if len(path) == 0 {
+			return true
+		}
+		path = strings.TrimPrefix(path, ".")
+	}
+}
+
+func (x *FieldMask) Reset() {
+	*x = FieldMask{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_google_protobuf_field_mask_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *FieldMask) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*FieldMask) ProtoMessage() {}
+
+func (x *FieldMask) ProtoReflect() protoreflect.Message {
+	mi := &file_google_protobuf_field_mask_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use FieldMask.ProtoReflect.Descriptor instead.
+func (*FieldMask) Descriptor() ([]byte, []int) {
+	return file_google_protobuf_field_mask_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *FieldMask) GetPaths() []string {
+	if x != nil {
+		return x.Paths
+	}
+	return nil
+}
+
+var File_google_protobuf_field_mask_proto protoreflect.FileDescriptor
+
+var file_google_protobuf_field_mask_proto_rawDesc = []byte{
+	0x0a, 0x20, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75,
+	0x66, 0x2f, 0x66, 0x69, 0x65, 0x6c, 0x64, 0x5f, 0x6d, 0x61, 0x73, 0x6b, 0x2e, 0x70, 0x72, 0x6f,
+	0x74, 0x6f, 0x12, 0x0f, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f,
+	0x62, 0x75, 0x66, 0x22, 0x21, 0x0a, 0x09, 0x46, 0x69, 0x65, 0x6c, 0x64, 0x4d, 0x61, 0x73, 0x6b,
+	0x12, 0x14, 0x0a, 0x05, 0x70, 0x61, 0x74, 0x68, 0x73, 0x18, 0x01, 0x20, 0x03, 0x28, 0x09, 0x52,
+	0x05, 0x70, 0x61, 0x74, 0x68, 0x73, 0x42, 0x85, 0x01, 0x0a, 0x13, 0x63, 0x6f, 0x6d, 0x2e, 0x67,
+	0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x42, 0x0e,
+	0x46, 0x69, 0x65, 0x6c, 0x64, 0x4d, 0x61, 0x73, 0x6b, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01,
+	0x5a, 0x32, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61, 0x6e, 0x67, 0x2e,
+	0x6f, 0x72, 0x67, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2f, 0x74, 0x79, 0x70,
+	0x65, 0x73, 0x2f, 0x6b, 0x6e, 0x6f, 0x77, 0x6e, 0x2f, 0x66, 0x69, 0x65, 0x6c, 0x64, 0x6d, 0x61,
+	0x73, 0x6b, 0x70, 0x62, 0xf8, 0x01, 0x01, 0xa2, 0x02, 0x03, 0x47, 0x50, 0x42, 0xaa, 0x02, 0x1e,
+	0x47, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e,
+	0x57, 0x65, 0x6c, 0x6c, 0x4b, 0x6e, 0x6f, 0x77, 0x6e, 0x54, 0x79, 0x70, 0x65, 0x73, 0x62, 0x06,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_google_protobuf_field_mask_proto_rawDescOnce sync.Once
+	file_google_protobuf_field_mask_proto_rawDescData = file_google_protobuf_field_mask_proto_rawDesc
+)
+
+func file_google_protobuf_field_mask_proto_rawDescGZIP() []byte {
+	file_google_protobuf_field_mask_proto_rawDescOnce.Do(func() {
+		file_google_protobuf_field_mask_proto_rawDescData = protoimpl.X.CompressGZIP(file_google_protobuf_field_mask_proto_rawDescData)
+	})
+	return file_google_protobuf_field_mask_proto_rawDescData
+}
+
+var file_google_protobuf_field_mask_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
+var file_google_protobuf_field_mask_proto_goTypes = []interface{}{
+	(*FieldMask)(nil), // 0: google.protobuf.FieldMask
+}
+var file_google_protobuf_field_mask_proto_depIdxs = []int32{
+	0, // [0:0] is the sub-list for method output_type
+	0, // [0:0] is the sub-list for method input_type
+	0, // [0:0] is the sub-list for extension type_name
+	0, // [0:0] is the sub-list for extension extendee
+	0, // [0:0] is the sub-list for field type_name
+}
+
+func init() { file_google_protobuf_field_mask_proto_init() }
+func file_google_protobuf_field_mask_proto_init() {
+	if File_google_protobuf_field_mask_proto != nil {
+		return
+	}
+	if !protoimpl.UnsafeEnabled {
+		file_google_protobuf_field_mask_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*FieldMask); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_google_protobuf_field_mask_proto_rawDesc,
+			NumEnums:      0,
+			NumMessages:   1,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_google_protobuf_field_mask_proto_goTypes,
+		DependencyIndexes: file_google_protobuf_field_mask_proto_depIdxs,
+		MessageInfos:      file_google_protobuf_field_mask_proto_msgTypes,
+	}.Build()
+	File_google_protobuf_field_mask_proto = out.File
+	file_google_protobuf_field_mask_proto_rawDesc = nil
+	file_google_protobuf_field_mask_proto_goTypes = nil
+	file_google_protobuf_field_mask_proto_depIdxs = nil
+}

vendor/modules.txt

@@ -6,9 +6,10 @@ cloud.google.com/go/internal
 cloud.google.com/go/internal/optional
 cloud.google.com/go/internal/trace
 cloud.google.com/go/internal/version
-# cloud.google.com/go/storage v1.16.0
+# cloud.google.com/go/storage v1.16.1
 ## explicit
 cloud.google.com/go/storage
+cloud.google.com/go/storage/internal/apiv2
 # github.com/VictoriaMetrics/fastcache v1.6.0
 ## explicit
 github.com/VictoriaMetrics/fastcache
@@ -114,6 +115,12 @@ github.com/golang/protobuf/ptypes/timestamp
 # github.com/golang/snappy v0.0.4
 ## explicit
 github.com/golang/snappy
+# github.com/google/go-cmp v0.5.6
+github.com/google/go-cmp/cmp
+github.com/google/go-cmp/cmp/internal/diff
+github.com/google/go-cmp/cmp/internal/flags
+github.com/google/go-cmp/cmp/internal/function
+github.com/google/go-cmp/cmp/internal/value
 # github.com/googleapis/gax-go/v2 v2.1.0
 github.com/googleapis/gax-go/v2
 github.com/googleapis/gax-go/v2/apierror
@@ -216,6 +223,7 @@ go.opencensus.io/internal
 go.opencensus.io/internal/tagencoding
 go.opencensus.io/metric/metricdata
 go.opencensus.io/metric/metricproducer
+go.opencensus.io/plugin/ocgrpc
 go.opencensus.io/plugin/ochttp
 go.opencensus.io/plugin/ochttp/propagation/b3
 go.opencensus.io/resource
@@ -278,6 +286,7 @@ google.golang.org/api/option
 google.golang.org/api/option/internaloption
 google.golang.org/api/storage/v1
 google.golang.org/api/transport/cert
+google.golang.org/api/transport/grpc
 google.golang.org/api/transport/http
 google.golang.org/api/transport/http/internal/propagation
 google.golang.org/api/transport/internal/dca
@@ -290,7 +299,9 @@ google.golang.org/appengine/internal/datastore
 google.golang.org/appengine/internal/log
 google.golang.org/appengine/internal/modules
 google.golang.org/appengine/internal/remote_api
+google.golang.org/appengine/internal/socket
 google.golang.org/appengine/internal/urlfetch
+google.golang.org/appengine/socket
 google.golang.org/appengine/urlfetch
 # google.golang.org/genproto v0.0.0-20210831024726-fe130286e0e2
 ## explicit
@@ -299,6 +310,8 @@ google.golang.org/genproto/googleapis/iam/v1
 google.golang.org/genproto/googleapis/rpc/code
 google.golang.org/genproto/googleapis/rpc/errdetails
 google.golang.org/genproto/googleapis/rpc/status
+google.golang.org/genproto/googleapis/storage/v2
+google.golang.org/genproto/googleapis/type/date
 google.golang.org/genproto/googleapis/type/expr
 # google.golang.org/grpc v1.40.0
 google.golang.org/grpc
@@ -306,12 +319,23 @@ google.golang.org/grpc/attributes
 google.golang.org/grpc/backoff
 google.golang.org/grpc/balancer
 google.golang.org/grpc/balancer/base
+google.golang.org/grpc/balancer/grpclb
+google.golang.org/grpc/balancer/grpclb/grpc_lb_v1
 google.golang.org/grpc/balancer/grpclb/state
 google.golang.org/grpc/balancer/roundrobin
 google.golang.org/grpc/binarylog/grpc_binarylog_v1
 google.golang.org/grpc/codes
 google.golang.org/grpc/connectivity
 google.golang.org/grpc/credentials
+google.golang.org/grpc/credentials/alts
+google.golang.org/grpc/credentials/alts/internal
+google.golang.org/grpc/credentials/alts/internal/authinfo
+google.golang.org/grpc/credentials/alts/internal/conn
+google.golang.org/grpc/credentials/alts/internal/handshaker
+google.golang.org/grpc/credentials/alts/internal/handshaker/service
+google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp
+google.golang.org/grpc/credentials/google
+google.golang.org/grpc/credentials/oauth
 google.golang.org/grpc/encoding
 google.golang.org/grpc/encoding/proto
 google.golang.org/grpc/grpclog
@@ -323,6 +347,7 @@ google.golang.org/grpc/internal/buffer
 google.golang.org/grpc/internal/channelz
 google.golang.org/grpc/internal/credentials
 google.golang.org/grpc/internal/envconfig
+google.golang.org/grpc/internal/googlecloud
 google.golang.org/grpc/internal/grpclog
 google.golang.org/grpc/internal/grpcrand
 google.golang.org/grpc/internal/grpcsync
@@ -377,6 +402,8 @@ google.golang.org/protobuf/runtime/protoimpl
 google.golang.org/protobuf/types/descriptorpb
 google.golang.org/protobuf/types/known/anypb
 google.golang.org/protobuf/types/known/durationpb
+google.golang.org/protobuf/types/known/emptypb
+google.golang.org/protobuf/types/known/fieldmaskpb
 google.golang.org/protobuf/types/known/timestamppb
 # gopkg.in/yaml.v2 v2.4.0
 ## explicit