wip

lib/logstorage/pattern.go

@@ -0,0 +1,185 @@
+package logstorage
+
+import (
+	"fmt"
+	"html"
+	"strconv"
+	"strings"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+)
+
+// pattern represents text pattern in the form 'some_text<some_field>other_text...'
+type pattern struct {
+	// steps contains steps for extracting fields from string
+	steps []patternStep
+
+	// matches contains matches for every step in steps
+	matches []string
+
+	// fields contains matches for non-empty fields
+	fields []patternField
+}
+
+type patternField struct {
+	name  string
+	value *string
+}
+
+type patternStep struct {
+	prefix string
+	field  string
+}
+
+func newPattern(steps []patternStep) *pattern {
+	if len(steps) == 0 {
+		logger.Panicf("BUG: steps cannot be empty")
+	}
+
+	matches := make([]string, len(steps))
+
+	var fields []patternField
+	for i, step := range steps {
+		if step.field != "" {
+			fields = append(fields, patternField{
+				name:  step.field,
+				value: &matches[i],
+			})
+		}
+	}
+	if len(fields) == 0 {
+		logger.Panicf("BUG: fields cannot be empty")
+	}
+
+	ef := &pattern{
+		steps:   steps,
+		matches: matches,
+		fields:  fields,
+	}
+	return ef
+}
+
+func (ef *pattern) apply(s string) {
+	clear(ef.matches)
+
+	steps := ef.steps
+
+	if prefix := steps[0].prefix; prefix != "" {
+		n := strings.Index(s, prefix)
+		if n < 0 {
+			// Mismatch
+			return
+		}
+		s = s[n+len(prefix):]
+	}
+
+	matches := ef.matches
+	for i := range steps {
+		nextPrefix := ""
+		if i+1 < len(steps) {
+			nextPrefix = steps[i+1].prefix
+		}
+
+		us, nOffset := tryUnquoteString(s)
+		if nOffset >= 0 {
+			// Matched quoted string
+			matches[i] = us
+			s = s[nOffset:]
+			if !strings.HasPrefix(s, nextPrefix) {
+				// Mismatch
+				return
+			}
+			s = s[len(nextPrefix):]
+		} else {
+			// Match unquoted string until the nextPrefix
+			if nextPrefix == "" {
+				matches[i] = s
+				return
+			}
+			n := strings.Index(s, nextPrefix)
+			if n < 0 {
+				// Mismatch
+				return
+			}
+			matches[i] = s[:n]
+			s = s[n+len(nextPrefix):]
+		}
+	}
+}
+
+func tryUnquoteString(s string) (string, int) {
+	if len(s) == 0 {
+		return s, -1
+	}
+	if s[0] != '"' && s[0] != '`' {
+		return s, -1
+	}
+	qp, err := strconv.QuotedPrefix(s)
+	if err != nil {
+		return s, -1
+	}
+	us, err := strconv.Unquote(qp)
+	if err != nil {
+		return s, -1
+	}
+	return us, len(qp)
+}
+
+func parsePatternSteps(s string) ([]patternStep, error) {
+	var steps []patternStep
+
+	hasNamedField := false
+
+	n := strings.IndexByte(s, '<')
+	if n < 0 {
+		return nil, fmt.Errorf("missing <...> fields")
+	}
+	prefix := s[:n]
+	s = s[n+1:]
+	for {
+		n := strings.IndexByte(s, '>')
+		if n < 0 {
+			return nil, fmt.Errorf("missing '>' for <%s", s)
+		}
+		field := s[:n]
+		s = s[n+1:]
+
+		if field == "_" || field == "*" {
+			field = ""
+		}
+		steps = append(steps, patternStep{
+			prefix: prefix,
+			field:  field,
+		})
+		if !hasNamedField && field != "" {
+			hasNamedField = true
+		}
+		if len(s) == 0 {
+			break
+		}
+
+		n = strings.IndexByte(s, '<')
+		if n < 0 {
+			steps = append(steps, patternStep{
+				prefix: s,
+			})
+			break
+		}
+		if n == 0 {
+			return nil, fmt.Errorf("missing delimiter after <%s>", field)
+		}
+		prefix = s[:n]
+		s = s[n+1:]
+	}
+
+	if !hasNamedField {
+		return nil, fmt.Errorf("missing named fields like <name>")
+	}
+
+	for i := range steps {
+		step := &steps[i]
+		step.prefix = html.UnescapeString(step.prefix)
+	}
+
+	return steps, nil
+}

lib/logstorage/pattern_test.go

@@ -0,0 +1,179 @@
+package logstorage
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestPatternApply(t *testing.T) {
+	f := func(pattern, s string, resultsExpected []string) {
+		t.Helper()
+
+		steps, err := parsePatternSteps(pattern)
+		if err != nil {
+			t.Fatalf("unexpected error: %s", err)
+		}
+		ef := newPattern(steps)
+		ef.apply(s)
+
+		if len(ef.fields) != len(resultsExpected) {
+			t.Fatalf("unexpected number of results; got %d; want %d", len(ef.fields), len(resultsExpected))
+		}
+		for i, f := range ef.fields {
+			if v := *f.value; v != resultsExpected[i] {
+				t.Fatalf("unexpected value for field %q; got %q; want %q", f.name, v, resultsExpected[i])
+			}
+		}
+	}
+
+	f("<foo>", "", []string{""})
+	f("<foo>", "abc", []string{"abc"})
+	f("<foo>bar", "", []string{""})
+	f("<foo>bar", "bar", []string{""})
+	f("<foo>bar", "bazbar", []string{"baz"})
+	f("<foo>bar", "a bazbar xdsf", []string{"a baz"})
+	f("<foo>bar<>", "a bazbar xdsf", []string{"a baz"})
+	f("<foo>bar<>x", "a bazbar xdsf", []string{"a baz"})
+	f("foo<bar>", "", []string{""})
+	f("foo<bar>", "foo", []string{""})
+	f("foo<bar>", "a foo xdf sdf", []string{" xdf sdf"})
+	f("foo<bar>", "a foo foobar", []string{" foobar"})
+	f("foo<bar>baz", "a foo foobar", []string{""})
+	f("foo<bar>baz", "a foobaz bar", []string{""})
+	f("foo<bar>baz", "a foo foobar baz", []string{" foobar "})
+	f("foo<bar>baz", "a foo foobar bazabc", []string{" foobar "})
+
+	f("ip=<ip> <> path=<path> ", "x=a, ip=1.2.3.4 method=GET host='abc' path=/foo/bar some tail here", []string{"1.2.3.4", "/foo/bar"})
+
+	// escaped pattern
+	f("ip=&lt;<ip>&gt;", "foo ip=<1.2.3.4> bar", []string{"1.2.3.4"})
+	f("ip=&lt;<ip>&gt;", "foo ip=<foo&amp;bar> bar", []string{"foo&amp;bar"})
+
+	// quoted fields
+	f(`"msg":<msg>,`, `{"foo":"bar","msg":"foo,b\"ar\n\t","baz":"x"}`, []string{`foo,b"ar` + "\n\t"})
+	f(`foo=<bar>`, "foo=`bar baz,abc` def", []string{"bar baz,abc"})
+	f(`foo=<bar> `, "foo=`bar baz,abc` def", []string{"bar baz,abc"})
+	f(`<foo>`, `"foo,\"bar"`, []string{`foo,"bar`})
+	f(`<foo>,"bar`, `"foo,\"bar"`, []string{`foo,"bar`})
+}
+
+func TestParsePatternStepsSuccess(t *testing.T) {
+	f := func(s string, stepsExpected []patternStep) {
+		t.Helper()
+
+		steps, err := parsePatternSteps(s)
+		if err != nil {
+			t.Fatalf("unexpected error when parsing %q: %s", s, err)
+		}
+		if !reflect.DeepEqual(steps, stepsExpected) {
+			t.Fatalf("unexpected steps for [%s]; got %v; want %v", s, steps, stepsExpected)
+		}
+	}
+
+	f("<foo>", []patternStep{
+		{
+			field: "foo",
+		},
+	})
+	f("<foo>bar", []patternStep{
+		{
+			field: "foo",
+		},
+		{
+			prefix: "bar",
+		},
+	})
+	f("<>bar<foo>", []patternStep{
+		{},
+		{
+			prefix: "bar",
+			field:  "foo",
+		},
+	})
+	f("bar<foo>", []patternStep{
+		{
+			prefix: "bar",
+			field:  "foo",
+		},
+	})
+	f("bar<foo>abc", []patternStep{
+		{
+			prefix: "bar",
+			field:  "foo",
+		},
+		{
+			prefix: "abc",
+		},
+	})
+	f("bar<foo>abc<_>", []patternStep{
+		{
+			prefix: "bar",
+			field:  "foo",
+		},
+		{
+			prefix: "abc",
+		},
+	})
+	f("<foo>bar<baz>", []patternStep{
+		{
+			field: "foo",
+		},
+		{
+			prefix: "bar",
+			field:  "baz",
+		},
+	})
+	f("bar<foo>baz", []patternStep{
+		{
+			prefix: "bar",
+			field:  "foo",
+		},
+		{
+			prefix: "baz",
+		},
+	})
+	f("&lt;<foo>&amp;gt;", []patternStep{
+		{
+			prefix: "<",
+			field:  "foo",
+		},
+		{
+			prefix: "&gt;",
+		},
+	})
+}
+
+func TestParsePatternStepsFailure(t *testing.T) {
+	f := func(s string) {
+		t.Helper()
+
+		_, err := parsePatternSteps(s)
+		if err == nil {
+			t.Fatalf("expecting non-nil error when parsing %q", s)
+		}
+	}
+
+	// empty string
+	f("")
+
+	// zero fields
+	f("foobar")
+
+	// Zero named fields
+	f("<>")
+	f("foo<>")
+	f("<>foo")
+	f("foo<_>bar<*>baz<>xxx")
+
+	// missing delimiter between fields
+	f("<foo><bar>")
+	f("<><bar>")
+	f("<foo><>")
+	f("bb<foo><><bar>aa")
+	f("aa<foo><bar>")
+	f("aa<foo><bar>bb")
+
+	// missing >
+	f("<foo")
+	f("foo<bar")
+}

lib/logstorage/pattern_timing_test.go

@@ -4,7 +4,7 @@ import (
 	"testing"
 )
 
-func BenchmarkExtractFormatApply(b *testing.B) {
+func BenchmarkPatternApply(b *testing.B) {
 	a := []string{
 		`{"level":"error","ts":1716113701.63973,"caller":"gcm/export.go:498","msg":"Failed to export self-observability metrics to Cloud Monitoring","error":"rpc error: code = PermissionDenied desc = Permission monitoring.timeSeries.create denied (or the resource may not exist).","stacktrace":"google3/cloud/kubernetes/metrics/common/gcm/gcm.(*exporter).startSelfObservability\n\tcloud/kubernetes/metrics/common/gcm/export.go:498","foo":"bar"}`,
 		`{"level":"error","ts":1716113370.2321634,"caller":"gcm/export.go:434","msg":"Failed to export metrics to Cloud Monitoring","error":"rpc error: code = PermissionDenied desc = Permission monitoring.timeSeries.create denied (or the resource may not exist).","stacktrace":"google3/cloud/kubernetes/metrics/common/gcm/gcm.(*exporter).exportBuffer\n\tcloud/kubernetes/metrics/common/gcm/export.go:434\ngoogle3/cloud/kubernetes/metrics/common/gcm/gcm.(*exporter).flush\n\tcloud/kubernetes/metrics/common/gcm/export.go:383\ngoogle3/cloud/kubernetes/metrics/common/gcm/gcm.(*exporter).Flush\n\tcloud/kubernetes/metrics/common/gcm/export.go:365\ngoogle3/cloud/kubernetes/metrics/components/collector/adapter/adapter.(*adapter).Finalize\n\tcloud/kubernetes/metrics/components/collector/adapter/consume.go:131\ngoogle3/cloud/kubernetes/metrics/components/collector/prometheus/prometheus.(*parser).ParseText\n\tcloud/kubernetes/metrics/components/collector/prometheus/parse.go:158\ngoogle3/cloud/kubernetes/metrics/components/collector/collector.runScrapeLoop\n\tcloud/kubernetes/metrics/components/collector/collector.go:103\ngoogle3/cloud/kubernetes/metrics/components/collector/collector.Run\n\tcloud/kubernetes/metrics/components/collector/collector.go:81\ngoogle3/cloud/kubernetes/metrics/components/collector/collector.Start.func1\n\tcloud/kubernetes/metrics/components/collector/multi_target_collector.go:45","foo":"bar"}`,
@@ -14,45 +14,45 @@ func BenchmarkExtractFormatApply(b *testing.B) {
 	}
 
 	b.Run("single-small-field-at-start", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"level":"<level>"`, a)
+		benchmarkPatternApply(b, `"level":"<level>"`, a)
 	})
 	b.Run("single-small-field-at-start-unquote", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"level":<level>`, a)
+		benchmarkPatternApply(b, `"level":<level>`, a)
 	})
 	b.Run("single-small-field-at-end", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"foo":"<foo>"`, a)
+		benchmarkPatternApply(b, `"foo":"<foo>"`, a)
 	})
 	b.Run("single-small-field-at-end-unquote", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"foo":<foo>`, a)
+		benchmarkPatternApply(b, `"foo":<foo>`, a)
 	})
 	b.Run("single-medium-field", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"msg":"<message>"`, a)
+		benchmarkPatternApply(b, `"msg":"<message>"`, a)
 	})
 	b.Run("single-medium-field-unquote", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"msg":<message>`, a)
+		benchmarkPatternApply(b, `"msg":<message>`, a)
 	})
 	b.Run("single-large-field", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"stacktrace":"<stacktrace>"`, a)
+		benchmarkPatternApply(b, `"stacktrace":"<stacktrace>"`, a)
 	})
 	b.Run("single-large-field-unquote", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"stacktrace":<stacktrace>`, a)
+		benchmarkPatternApply(b, `"stacktrace":<stacktrace>`, a)
 	})
 	b.Run("two-fields", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"level":"<level>",<_>"msg":"<msg>"`, a)
+		benchmarkPatternApply(b, `"level":"<level>",<_>"msg":"<msg>"`, a)
 	})
 	b.Run("two-fields-unquote", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"level":<level>,<_>"msg":<msg>`, a)
+		benchmarkPatternApply(b, `"level":<level>,<_>"msg":<msg>`, a)
 	})
 	b.Run("many-fields", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"level":"<level>","ts":"<ts>","caller":"<caller>","msg":"<msg>","error":"<error>"`, a)
+		benchmarkPatternApply(b, `"level":"<level>","ts":"<ts>","caller":"<caller>","msg":"<msg>","error":"<error>"`, a)
 	})
 	b.Run("many-fields-unquote", func(b *testing.B) {
-		benchmarkExtractFormatApply(b, `"level":<level>,"ts":<ts>,"caller":<caller>,"msg":<msg>,"error":<error>`, a)
+		benchmarkPatternApply(b, `"level":<level>,"ts":<ts>,"caller":<caller>,"msg":<msg>,"error":<error>`, a)
 	})
 }
 
-func benchmarkExtractFormatApply(b *testing.B, pattern string, a []string) {
+func benchmarkPatternApply(b *testing.B, pattern string, a []string) {
-	steps, err := parseExtractFormatSteps(pattern)
+	steps, err := parsePatternSteps(pattern)
 	if err != nil {
 		b.Fatalf("unexpected error: %s", err)
 	}
@@ -66,7 +66,7 @@ func benchmarkExtractFormatApply(b *testing.B, pattern string, a []string) {
 	b.SetBytes(int64(n))
 	b.RunParallel(func(pb *testing.PB) {
 		sink := 0
-		ef := newExtractFormat(steps)
+		ef := newPattern(steps)
 		for pb.Next() {
 			for _, s := range a {
 				ef.apply(s)

lib/logstorage/pipe_extract.go

@@ -2,12 +2,7 @@ package logstorage
 
 import (
 	"fmt"
-	"html"
-	"strconv"
-	"strings"
 	"unsafe"
-
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 )
 
 // pipeExtract processes '| extract from <field> <pattern>' pipe.
@@ -15,7 +10,7 @@ import (
 // See https://docs.victoriametrics.com/victorialogs/logsql/#extract-pipe
 type pipeExtract struct {
 	fromField string
-	steps     []extractFormatStep
+	steps     []patternStep
 
 	pattern string
 }
@@ -63,7 +58,7 @@ func (pe *pipeExtract) updateNeededFields(neededFields, unneededFields fieldsSet
 func (pe *pipeExtract) newPipeProcessor(workersCount int, _ <-chan struct{}, _ func(), ppBase pipeProcessor) pipeProcessor {
 	shards := make([]pipeExtractProcessorShard, workersCount)
 	for i := range shards {
-		ef := newExtractFormat(pe.steps)
+		ef := newPattern(pe.steps)
 		rcs := make([]resultColumn, len(ef.fields))
 		for j := range rcs {
 			rcs[j].name = ef.fields[j].name
@@ -100,7 +95,7 @@ type pipeExtractProcessorShard struct {
 }
 
 type pipeExtractProcessorShardNopad struct {
-	ef *extractFormat
+	ef *pattern
 
 	rcs []resultColumn
 }
@@ -169,7 +164,7 @@ func parsePipeExtract(lex *lexer) (*pipeExtract, error) {
 	if err != nil {
 		return nil, fmt.Errorf("cannot read 'pattern': %w", err)
 	}
-	steps, err := parseExtractFormatSteps(pattern)
+	steps, err := parsePatternSteps(pattern)
 	if err != nil {
 		return nil, fmt.Errorf("cannot parse 'pattern' %q: %w", pattern, err)
 	}
@@ -181,177 +176,3 @@ func parsePipeExtract(lex *lexer) (*pipeExtract, error) {
 	}
 	return pe, nil
 }
-
-type extractFormat struct {
-	// steps contains steps for extracting fields from string
-	steps []extractFormatStep
-
-	// matches contains matches for every step in steps
-	matches []string
-
-	// fields contains matches for non-empty fields
-	fields []extractField
-}
-
-type extractField struct {
-	name  string
-	value *string
-}
-
-type extractFormatStep struct {
-	prefix string
-	field  string
-}
-
-func newExtractFormat(steps []extractFormatStep) *extractFormat {
-	if len(steps) == 0 {
-		logger.Panicf("BUG: steps cannot be empty")
-	}
-
-	matches := make([]string, len(steps))
-
-	var fields []extractField
-	for i, step := range steps {
-		if step.field != "" {
-			fields = append(fields, extractField{
-				name:  step.field,
-				value: &matches[i],
-			})
-		}
-	}
-	if len(fields) == 0 {
-		logger.Panicf("BUG: fields cannot be empty")
-	}
-
-	ef := &extractFormat{
-		steps:   steps,
-		matches: matches,
-		fields:  fields,
-	}
-	return ef
-}
-
-func (ef *extractFormat) apply(s string) {
-	clear(ef.matches)
-
-	steps := ef.steps
-
-	if prefix := steps[0].prefix; prefix != "" {
-		n := strings.Index(s, prefix)
-		if n < 0 {
-			// Mismatch
-			return
-		}
-		s = s[n+len(prefix):]
-	}
-
-	matches := ef.matches
-	for i := range steps {
-		nextPrefix := ""
-		if i+1 < len(steps) {
-			nextPrefix = steps[i+1].prefix
-		}
-
-		us, nOffset := tryUnquoteString(s)
-		if nOffset >= 0 {
-			// Matched quoted string
-			matches[i] = us
-			s = s[nOffset:]
-			if !strings.HasPrefix(s, nextPrefix) {
-				// Mismatch
-				return
-			}
-			s = s[len(nextPrefix):]
-		} else {
-			// Match unquoted string until the nextPrefix
-			if nextPrefix == "" {
-				matches[i] = s
-				return
-			}
-			n := strings.Index(s, nextPrefix)
-			if n < 0 {
-				// Mismatch
-				return
-			}
-			matches[i] = s[:n]
-			s = s[n+len(nextPrefix):]
-		}
-	}
-}
-
-func tryUnquoteString(s string) (string, int) {
-	if len(s) == 0 {
-		return s, -1
-	}
-	if s[0] != '"' && s[0] != '`' {
-		return s, -1
-	}
-	qp, err := strconv.QuotedPrefix(s)
-	if err != nil {
-		return s, -1
-	}
-	us, err := strconv.Unquote(qp)
-	if err != nil {
-		return s, -1
-	}
-	return us, len(qp)
-}
-
-func parseExtractFormatSteps(s string) ([]extractFormatStep, error) {
-	var steps []extractFormatStep
-
-	hasNamedField := false
-
-	n := strings.IndexByte(s, '<')
-	if n < 0 {
-		return nil, fmt.Errorf("missing <...> fields")
-	}
-	prefix := s[:n]
-	s = s[n+1:]
-	for {
-		n := strings.IndexByte(s, '>')
-		if n < 0 {
-			return nil, fmt.Errorf("missing '>' for <%s", s)
-		}
-		field := s[:n]
-		s = s[n+1:]
-
-		if field == "_" || field == "*" {
-			field = ""
-		}
-		steps = append(steps, extractFormatStep{
-			prefix: prefix,
-			field:  field,
-		})
-		if !hasNamedField && field != "" {
-			hasNamedField = true
-		}
-		if len(s) == 0 {
-			break
-		}
-
-		n = strings.IndexByte(s, '<')
-		if n < 0 {
-			steps = append(steps, extractFormatStep{
-				prefix: s,
-			})
-			break
-		}
-		if n == 0 {
-			return nil, fmt.Errorf("missing delimiter after <%s>", field)
-		}
-		prefix = s[:n]
-		s = s[n+1:]
-	}
-
-	if !hasNamedField {
-		return nil, fmt.Errorf("missing named fields like <name>")
-	}
-
-	for i := range steps {
-		step := &steps[i]
-		step.prefix = html.UnescapeString(step.prefix)
-	}
-
-	return steps, nil
-}

lib/logstorage/pipe_extract_test.go

@@ -1,183 +1,9 @@
 package logstorage
 
 import (
-	"reflect"
 	"testing"
 )
 
-func TestExtractFormatApply(t *testing.T) {
-	f := func(pattern, s string, resultsExpected []string) {
-		t.Helper()
-
-		steps, err := parseExtractFormatSteps(pattern)
-		if err != nil {
-			t.Fatalf("unexpected error: %s", err)
-		}
-		ef := newExtractFormat(steps)
-		ef.apply(s)
-
-		if len(ef.fields) != len(resultsExpected) {
-			t.Fatalf("unexpected number of results; got %d; want %d", len(ef.fields), len(resultsExpected))
-		}
-		for i, f := range ef.fields {
-			if v := *f.value; v != resultsExpected[i] {
-				t.Fatalf("unexpected value for field %q; got %q; want %q", f.name, v, resultsExpected[i])
-			}
-		}
-	}
-
-	f("<foo>", "", []string{""})
-	f("<foo>", "abc", []string{"abc"})
-	f("<foo>bar", "", []string{""})
-	f("<foo>bar", "bar", []string{""})
-	f("<foo>bar", "bazbar", []string{"baz"})
-	f("<foo>bar", "a bazbar xdsf", []string{"a baz"})
-	f("<foo>bar<>", "a bazbar xdsf", []string{"a baz"})
-	f("<foo>bar<>x", "a bazbar xdsf", []string{"a baz"})
-	f("foo<bar>", "", []string{""})
-	f("foo<bar>", "foo", []string{""})
-	f("foo<bar>", "a foo xdf sdf", []string{" xdf sdf"})
-	f("foo<bar>", "a foo foobar", []string{" foobar"})
-	f("foo<bar>baz", "a foo foobar", []string{""})
-	f("foo<bar>baz", "a foobaz bar", []string{""})
-	f("foo<bar>baz", "a foo foobar baz", []string{" foobar "})
-	f("foo<bar>baz", "a foo foobar bazabc", []string{" foobar "})
-
-	f("ip=<ip> <> path=<path> ", "x=a, ip=1.2.3.4 method=GET host='abc' path=/foo/bar some tail here", []string{"1.2.3.4", "/foo/bar"})
-
-	// escaped pattern
-	f("ip=&lt;<ip>&gt;", "foo ip=<1.2.3.4> bar", []string{"1.2.3.4"})
-	f("ip=&lt;<ip>&gt;", "foo ip=<foo&amp;bar> bar", []string{"foo&amp;bar"})
-
-	// quoted fields
-	f(`"msg":<msg>,`, `{"foo":"bar","msg":"foo,b\"ar\n\t","baz":"x"}`, []string{`foo,b"ar` + "\n\t"})
-	f(`foo=<bar>`, "foo=`bar baz,abc` def", []string{"bar baz,abc"})
-	f(`foo=<bar> `, "foo=`bar baz,abc` def", []string{"bar baz,abc"})
-	f(`<foo>`, `"foo,\"bar"`, []string{`foo,"bar`})
-	f(`<foo>,"bar`, `"foo,\"bar"`, []string{`foo,"bar`})
-}
-
-func TestParseExtractFormatStepsSuccess(t *testing.T) {
-	f := func(s string, stepsExpected []extractFormatStep) {
-		t.Helper()
-
-		steps, err := parseExtractFormatSteps(s)
-		if err != nil {
-			t.Fatalf("unexpected error when parsing %q: %s", s, err)
-		}
-		if !reflect.DeepEqual(steps, stepsExpected) {
-			t.Fatalf("unexpected steps for [%s]; got %v; want %v", s, steps, stepsExpected)
-		}
-	}
-
-	f("<foo>", []extractFormatStep{
-		{
-			field: "foo",
-		},
-	})
-	f("<foo>bar", []extractFormatStep{
-		{
-			field: "foo",
-		},
-		{
-			prefix: "bar",
-		},
-	})
-	f("<>bar<foo>", []extractFormatStep{
-		{},
-		{
-			prefix: "bar",
-			field:  "foo",
-		},
-	})
-	f("bar<foo>", []extractFormatStep{
-		{
-			prefix: "bar",
-			field:  "foo",
-		},
-	})
-	f("bar<foo>abc", []extractFormatStep{
-		{
-			prefix: "bar",
-			field:  "foo",
-		},
-		{
-			prefix: "abc",
-		},
-	})
-	f("bar<foo>abc<_>", []extractFormatStep{
-		{
-			prefix: "bar",
-			field:  "foo",
-		},
-		{
-			prefix: "abc",
-		},
-	})
-	f("<foo>bar<baz>", []extractFormatStep{
-		{
-			field: "foo",
-		},
-		{
-			prefix: "bar",
-			field:  "baz",
-		},
-	})
-	f("bar<foo>baz", []extractFormatStep{
-		{
-			prefix: "bar",
-			field:  "foo",
-		},
-		{
-			prefix: "baz",
-		},
-	})
-	f("&lt;<foo>&amp;gt;", []extractFormatStep{
-		{
-			prefix: "<",
-			field:  "foo",
-		},
-		{
-			prefix: "&gt;",
-		},
-	})
-}
-
-func TestParseExtractFormatStepFailure(t *testing.T) {
-	f := func(s string) {
-		t.Helper()
-
-		_, err := parseExtractFormatSteps(s)
-		if err == nil {
-			t.Fatalf("expecting non-nil error when parsing %q", s)
-		}
-	}
-
-	// empty string
-	f("")
-
-	// zero fields
-	f("foobar")
-
-	// Zero named fields
-	f("<>")
-	f("foo<>")
-	f("<>foo")
-	f("foo<_>bar<*>baz<>xxx")
-
-	// missing delimiter between fields
-	f("<foo><bar>")
-	f("<><bar>")
-	f("<foo><>")
-	f("bb<foo><><bar>aa")
-	f("aa<foo><bar>")
-	f("aa<foo><bar>bb")
-
-	// missing >
-	f("<foo")
-	f("foo<bar")
-}
-
 func TestPipeExtractUpdateNeededFields(t *testing.T) {
 	f := func(s string, neededFields, unneededFields, neededFieldsExpected, unneededFieldsExpected string) {
 		t.Helper()