VictoriaMetrics/vendor/google.golang.org/grpc/codec.go
2024-09-08 21:05:06 +02:00

105 lines
3.1 KiB
Go

/*
*
* Copyright 2014 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 grpc
import (
"google.golang.org/grpc/encoding"
_ "google.golang.org/grpc/encoding/proto" // to register the Codec for "proto"
"google.golang.org/grpc/mem"
)
// baseCodec captures the new encoding.CodecV2 interface without the Name
// function, allowing it to be implemented by older Codec and encoding.Codec
// implementations. The omitted Name function is only needed for the register in
// the encoding package and is not part of the core functionality.
type baseCodec interface {
Marshal(v any) (mem.BufferSlice, error)
Unmarshal(data mem.BufferSlice, v any) error
}
// getCodec returns an encoding.CodecV2 for the codec of the given name (if
// registered). Initially checks the V2 registry with encoding.GetCodecV2 and
// returns the V2 codec if it is registered. Otherwise, it checks the V1 registry
// with encoding.GetCodec and if it is registered wraps it with newCodecV1Bridge
// to turn it into an encoding.CodecV2. Returns nil otherwise.
func getCodec(name string) encoding.CodecV2 {
if codecV1 := encoding.GetCodec(name); codecV1 != nil {
return newCodecV1Bridge(codecV1)
}
return encoding.GetCodecV2(name)
}
func newCodecV0Bridge(c Codec) baseCodec {
return codecV0Bridge{codec: c}
}
func newCodecV1Bridge(c encoding.Codec) encoding.CodecV2 {
return codecV1Bridge{
codecV0Bridge: codecV0Bridge{codec: c},
name: c.Name(),
}
}
var _ baseCodec = codecV0Bridge{}
type codecV0Bridge struct {
codec interface {
Marshal(v any) ([]byte, error)
Unmarshal(data []byte, v any) error
}
}
func (c codecV0Bridge) Marshal(v any) (mem.BufferSlice, error) {
data, err := c.codec.Marshal(v)
if err != nil {
return nil, err
}
return mem.BufferSlice{mem.NewBuffer(&data, nil)}, nil
}
func (c codecV0Bridge) Unmarshal(data mem.BufferSlice, v any) (err error) {
return c.codec.Unmarshal(data.Materialize(), v)
}
var _ encoding.CodecV2 = codecV1Bridge{}
type codecV1Bridge struct {
codecV0Bridge
name string
}
func (c codecV1Bridge) Name() string {
return c.name
}
// Codec defines the interface gRPC uses to encode and decode messages.
// Note that implementations of this interface must be thread safe;
// a Codec's methods can be called from concurrent goroutines.
//
// Deprecated: use encoding.Codec instead.
type Codec interface {
// Marshal returns the wire format of v.
Marshal(v any) ([]byte, error)
// Unmarshal parses the wire format into v.
Unmarshal(data []byte, v any) error
// String returns the name of the Codec implementation. This is unused by
// gRPC.
String() string
}