Feat/bridge support text map (#2911)

* feat: support TextMap

* doc: add comment

* test: support for ot.TextMap

* Retrieve lost code due to merge

* fix: retrieve lost code due to merge. test: support for ot.HTTPHeaders

* go mod tidy

* Optimized code style, add changelog

* doc: Restore comments

* wip: add test cases

* test: fix args error

* delete empty line

* Fix syntax and changelog errors

* Fix formatting errors

Co-authored-by: Chester Cheung <cheung.zhy.csu@gmail.com>
Co-authored-by: Anthony Mirabella <a9@aneurysm9.com>

CHANGELOG.md

@@ -8,6 +8,11 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
+### Added
+
+- Add support for `opentracing.TextMap` format in the `Inject` and `Extract` methods
+of the `"go.opentelemetry.io/otel/bridge/opentracing".BridgeTracer` type. (#2911)
+
 ### Changed
 
 - The `crosslink` make target has been updated to use the `go.opentelemetry.io/build-tools/crosslink` package. (#2886)

bridge/opentracing/bridge.go

@@ -634,7 +634,7 @@ func (s fakeSpan) SpanContext() trace.SpanContext {
 // Inject is a part of the implementation of the OpenTracing Tracer
 // interface.
 //
-// Currently only the HTTPHeaders format is supported.
+// Currently only the HTTPHeaders and TextMap formats are supported.
 func (t *BridgeTracer) Inject(sm ot.SpanContext, format interface{}, carrier interface{}) error {
 	bridgeSC, ok := sm.(*bridgeSpanContext)
 	if !ok {
@@ -643,38 +643,75 @@ func (t *BridgeTracer) Inject(sm ot.SpanContext, format interface{}, carrier int
 	if !bridgeSC.otelSpanContext.IsValid() {
 		return ot.ErrInvalidSpanContext
 	}
-	if builtinFormat, ok := format.(ot.BuiltinFormat); !ok || builtinFormat != ot.HTTPHeaders {
+
+	builtinFormat, ok := format.(ot.BuiltinFormat)
+	if !ok {
 		return ot.ErrUnsupportedFormat
 	}
-	hhcarrier, ok := carrier.(ot.HTTPHeadersCarrier)
-	if !ok {
-		return ot.ErrInvalidCarrier
+
+	var textCarrier propagation.TextMapCarrier
+
+	switch builtinFormat {
+	case ot.HTTPHeaders:
+		hhcarrier, ok := carrier.(ot.HTTPHeadersCarrier)
+		if !ok {
+			return ot.ErrInvalidCarrier
+		}
+
+		textCarrier = propagation.HeaderCarrier(hhcarrier)
+	case ot.TextMap:
+		if textCarrier, ok = carrier.(propagation.TextMapCarrier); !ok {
+			var err error
+			if textCarrier, err = newTextMapWrapperForInject(carrier); err != nil {
+				return err
+			}
+		}
+	default:
+		return ot.ErrUnsupportedFormat
 	}
-	header := http.Header(hhcarrier)
+
 	fs := fakeSpan{
 		Span: noopSpan,
 		sc:   bridgeSC.otelSpanContext,
 	}
 	ctx := trace.ContextWithSpan(context.Background(), fs)
 	ctx = baggage.ContextWithBaggage(ctx, bridgeSC.bag)
-	t.getPropagator().Inject(ctx, propagation.HeaderCarrier(header))
+	t.getPropagator().Inject(ctx, textCarrier)
 	return nil
 }
 
 // Extract is a part of the implementation of the OpenTracing Tracer
 // interface.
 //
-// Currently only the HTTPHeaders format is supported.
+// Currently only the HTTPHeaders and TextMap formats are supported.
 func (t *BridgeTracer) Extract(format interface{}, carrier interface{}) (ot.SpanContext, error) {
-	if builtinFormat, ok := format.(ot.BuiltinFormat); !ok || builtinFormat != ot.HTTPHeaders {
+	builtinFormat, ok := format.(ot.BuiltinFormat)
+	if !ok {
 		return nil, ot.ErrUnsupportedFormat
 	}
-	hhcarrier, ok := carrier.(ot.HTTPHeadersCarrier)
-	if !ok {
-		return nil, ot.ErrInvalidCarrier
+
+	var textCarrier propagation.TextMapCarrier
+
+	switch builtinFormat {
+	case ot.HTTPHeaders:
+		hhcarrier, ok := carrier.(ot.HTTPHeadersCarrier)
+		if !ok {
+			return nil, ot.ErrInvalidCarrier
+		}
+
+		textCarrier = propagation.HeaderCarrier(hhcarrier)
+	case ot.TextMap:
+		if textCarrier, ok = carrier.(propagation.TextMapCarrier); !ok {
+			var err error
+			if textCarrier, err = newTextMapWrapperForExtract(carrier); err != nil {
+				return nil, err
+			}
+		}
+	default:
+		return nil, ot.ErrUnsupportedFormat
 	}
-	header := http.Header(hhcarrier)
-	ctx := t.getPropagator().Extract(context.Background(), propagation.HeaderCarrier(header))
+
+	ctx := t.getPropagator().Extract(context.Background(), textCarrier)
 	bag := baggage.FromContext(ctx)
 	bridgeSC := &bridgeSpanContext{
 		bag:             bag,
@@ -692,3 +729,105 @@ func (t *BridgeTracer) getPropagator() propagation.TextMapPropagator {
 	}
 	return otel.GetTextMapPropagator()
 }
+
+// textMapWrapper Provides operating.TextMapWriter and operating.TextMapReader to
+// propagation.TextMapCarrier compatibility.
+// Usually, Inject method will only use the write-related interface.
+// Extract method will only use the reade-related interface.
+// To avoid panic,
+// when the carrier implements only one of the interfaces,
+// it provides a default implementation of the other interface (textMapWriter and textMapReader).
+type textMapWrapper struct {
+	ot.TextMapWriter
+	ot.TextMapReader
+	readerMap map[string]string
+}
+
+func (t *textMapWrapper) Get(key string) string {
+	if t.readerMap == nil {
+		t.loadMap()
+	}
+
+	return t.readerMap[key]
+}
+
+func (t *textMapWrapper) Set(key string, value string) {
+	t.TextMapWriter.Set(key, value)
+}
+
+func (t *textMapWrapper) Keys() []string {
+	if t.readerMap == nil {
+		t.loadMap()
+	}
+
+	str := make([]string, 0, len(t.readerMap))
+	for key := range t.readerMap {
+		str = append(str, key)
+	}
+
+	return str
+}
+
+func (t *textMapWrapper) loadMap() {
+	t.readerMap = make(map[string]string)
+
+	_ = t.ForeachKey(func(key, val string) error {
+		t.readerMap[key] = val
+
+		return nil
+	})
+}
+
+func newTextMapWrapperForExtract(carrier interface{}) (*textMapWrapper, error) {
+	t := &textMapWrapper{}
+
+	reader, ok := carrier.(ot.TextMapReader)
+	if !ok {
+		return nil, ot.ErrInvalidCarrier
+	}
+
+	t.TextMapReader = reader
+
+	writer, ok := carrier.(ot.TextMapWriter)
+	if ok {
+		t.TextMapWriter = writer
+	} else {
+		t.TextMapWriter = &textMapWriter{}
+	}
+
+	return t, nil
+}
+
+func newTextMapWrapperForInject(carrier interface{}) (*textMapWrapper, error) {
+	t := &textMapWrapper{}
+
+	writer, ok := carrier.(ot.TextMapWriter)
+	if !ok {
+		return nil, ot.ErrInvalidCarrier
+	}
+
+	t.TextMapWriter = writer
+
+	reader, ok := carrier.(ot.TextMapReader)
+	if ok {
+		t.TextMapReader = reader
+	} else {
+		t.TextMapReader = &textMapReader{}
+	}
+
+	return t, nil
+}
+
+type textMapWriter struct {
+}
+
+func (t *textMapWriter) Set(key string, value string) {
+	// maybe print a warning log.
+}
+
+type textMapReader struct {
+}
+
+func (t *textMapReader) ForeachKey(handler func(key, val string) error) error {
+	return nil // maybe print a warning log.
+}

bridge/opentracing/bridge_test.go

@@ -0,0 +1,362 @@
+// Copyright The OpenTelemetry 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 opentracing
+
+import (
+	"context"
+	"errors"
+	"net/http"
+	"strings"
+	"testing"
+
+	ot "github.com/opentracing/opentracing-go"
+	"github.com/stretchr/testify/assert"
+
+	"go.opentelemetry.io/otel/propagation"
+	"go.opentelemetry.io/otel/trace"
+)
+
+type testOnlyTextMapReader struct {
+}
+
+func newTestOnlyTextMapReader() *testOnlyTextMapReader {
+	return &testOnlyTextMapReader{}
+}
+
+func (t *testOnlyTextMapReader) ForeachKey(handler func(key string, val string) error) error {
+	_ = handler("key1", "val1")
+	_ = handler("key2", "val2")
+
+	return nil
+}
+
+type testOnlyTextMapWriter struct {
+	m map[string]string
+}
+
+func newTestOnlyTextMapWriter() *testOnlyTextMapWriter {
+	return &testOnlyTextMapWriter{m: map[string]string{}}
+}
+
+func (t *testOnlyTextMapWriter) Set(key, val string) {
+	t.m[key] = val
+}
+
+type testTextMapReaderAndWriter struct {
+	*testOnlyTextMapReader
+	*testOnlyTextMapWriter
+}
+
+func newTestTextMapReaderAndWriter() *testTextMapReaderAndWriter {
+	return &testTextMapReaderAndWriter{
+		testOnlyTextMapReader: newTestOnlyTextMapReader(),
+		testOnlyTextMapWriter: newTestOnlyTextMapWriter(),
+	}
+}
+
+func TestTextMapWrapper_New(t *testing.T) {
+	_, err := newTextMapWrapperForExtract(newTestOnlyTextMapReader())
+	assert.NoError(t, err)
+
+	_, err = newTextMapWrapperForExtract(newTestOnlyTextMapWriter())
+	assert.True(t, errors.Is(err, ot.ErrInvalidCarrier))
+
+	_, err = newTextMapWrapperForExtract(newTestTextMapReaderAndWriter())
+	assert.NoError(t, err)
+
+	_, err = newTextMapWrapperForInject(newTestOnlyTextMapWriter())
+	assert.NoError(t, err)
+
+	_, err = newTextMapWrapperForInject(newTestOnlyTextMapReader())
+	assert.True(t, errors.Is(err, ot.ErrInvalidCarrier))
+
+	_, err = newTextMapWrapperForInject(newTestTextMapReaderAndWriter())
+	assert.NoError(t, err)
+}
+
+func TestTextMapWrapper_action(t *testing.T) {
+	testExtractFunc := func(carrier propagation.TextMapCarrier) {
+		str := carrier.Keys()
+		assert.Len(t, str, 2)
+		assert.Contains(t, str, "key1", "key2")
+
+		assert.Equal(t, carrier.Get("key1"), "val1")
+		assert.Equal(t, carrier.Get("key2"), "val2")
+	}
+
+	testInjectFunc := func(carrier propagation.TextMapCarrier) {
+		carrier.Set("key1", "val1")
+		carrier.Set("key2", "val2")
+
+		wrap, ok := carrier.(*textMapWrapper)
+		assert.True(t, ok)
+
+		writer, ok := wrap.TextMapWriter.(*testOnlyTextMapWriter)
+		if ok {
+			assert.Contains(t, writer.m, "key1", "key2", "val1", "val2")
+			return
+		}
+
+		writer2, ok := wrap.TextMapWriter.(*testTextMapReaderAndWriter)
+		assert.True(t, ok)
+		assert.Contains(t, writer2.m, "key1", "key2", "val1", "val2")
+	}
+
+	onlyWriter, err := newTextMapWrapperForExtract(newTestOnlyTextMapReader())
+	assert.NoError(t, err)
+	testExtractFunc(onlyWriter)
+
+	onlyReader, err := newTextMapWrapperForInject(&testOnlyTextMapWriter{m: map[string]string{}})
+	assert.NoError(t, err)
+	testInjectFunc(onlyReader)
+
+	both, err := newTextMapWrapperForExtract(newTestTextMapReaderAndWriter())
+	assert.NoError(t, err)
+	testExtractFunc(both)
+
+	both, err = newTextMapWrapperForInject(newTestTextMapReaderAndWriter())
+	assert.NoError(t, err)
+	testInjectFunc(both)
+}
+
+var (
+	testHeader               = "test-trace-id"
+	traceID    trace.TraceID = [16]byte{byte(10)}
+	spanID     trace.SpanID  = [8]byte{byte(11)}
+)
+
+type testTextMapPropagator struct {
+}
+
+func (t testTextMapPropagator) Inject(ctx context.Context, carrier propagation.TextMapCarrier) {
+	carrier.Set(testHeader, strings.Join([]string{traceID.String(), spanID.String()}, ":"))
+
+	// Test for panic
+	_ = carrier.Get("test")
+	_ = carrier.Keys()
+}
+
+func (t testTextMapPropagator) Extract(ctx context.Context, carrier propagation.TextMapCarrier) context.Context {
+	traces := carrier.Get(testHeader)
+
+	str := strings.Split(traces, ":")
+	if len(str) != 2 {
+		return ctx
+	}
+
+	var exist = false
+
+	for _, key := range carrier.Keys() {
+		if strings.EqualFold(testHeader, key) {
+			exist = true
+
+			break
+		}
+	}
+
+	if !exist {
+		return ctx
+	}
+
+	var (
+		traceID, _ = trace.TraceIDFromHex(str[0])
+		spanID, _  = trace.SpanIDFromHex(str[1])
+		sc         = trace.NewSpanContext(trace.SpanContextConfig{
+			TraceID: traceID,
+			SpanID:  spanID,
+		})
+	)
+
+	// Test for panic
+	carrier.Set("key", "val")
+
+	return trace.ContextWithRemoteSpanContext(ctx, sc)
+}
+
+func (t testTextMapPropagator) Fields() []string {
+	return []string{"test"}
+}
+
+// textMapCarrier  Implemented propagation.TextMapCarrier interface.
+type textMapCarrier struct {
+	m map[string]string
+}
+
+func newTextCarrier() *textMapCarrier {
+	return &textMapCarrier{m: map[string]string{}}
+}
+
+func (t *textMapCarrier) Get(key string) string {
+	return t.m[key]
+}
+
+func (t *textMapCarrier) Set(key string, value string) {
+	t.m[key] = value
+}
+
+func (t *textMapCarrier) Keys() []string {
+	str := make([]string, 0, len(t.m))
+
+	for key := range t.m {
+		str = append(str, key)
+	}
+
+	return str
+}
+
+// testTextMapReader only implemented opentracing.TextMapReader interface.
+type testTextMapReader struct {
+	m *map[string]string
+}
+
+func newTestTextMapReader(m *map[string]string) *testTextMapReader {
+	return &testTextMapReader{m: m}
+}
+
+func (t *testTextMapReader) ForeachKey(handler func(key string, val string) error) error {
+	for key, val := range *t.m {
+		if err := handler(key, val); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// testTextMapWriter only implemented opentracing.TextMapWriter interface.
+type testTextMapWriter struct {
+	m *map[string]string
+}
+
+func newTestTextMapWriter(m *map[string]string) *testTextMapWriter {
+	return &testTextMapWriter{m: m}
+}
+
+func (t *testTextMapWriter) Set(key, val string) {
+	(*t.m)[key] = val
+}
+
+func TestBridgeTracer_ExtractAndInject(t *testing.T) {
+	bridge := NewBridgeTracer()
+	bridge.SetTextMapPropagator(new(testTextMapPropagator))
+
+	tmc := newTextCarrier()
+	shareMap := map[string]string{}
+	otTextMap := ot.TextMapCarrier{}
+	httpHeader := ot.HTTPHeadersCarrier(http.Header{})
+
+	testCases := []struct {
+		name               string
+		injectCarrierType  ot.BuiltinFormat
+		extractCarrierType ot.BuiltinFormat
+		extractCarrier     interface{}
+		injectCarrier      interface{}
+		extractErr         error
+		injectErr          error
+	}{
+		{
+			name:               "support for propagation.TextMapCarrier",
+			injectCarrierType:  ot.TextMap,
+			injectCarrier:      tmc,
+			extractCarrierType: ot.TextMap,
+			extractCarrier:     tmc,
+		},
+		{
+			name:               "support for opentracing.TextMapReader and opentracing.TextMapWriter",
+			injectCarrierType:  ot.TextMap,
+			injectCarrier:      otTextMap,
+			extractCarrierType: ot.TextMap,
+			extractCarrier:     otTextMap,
+		},
+		{
+			name:               "support for HTTPHeaders",
+			injectCarrierType:  ot.HTTPHeaders,
+			injectCarrier:      httpHeader,
+			extractCarrierType: ot.HTTPHeaders,
+			extractCarrier:     httpHeader,
+		},
+		{
+			name:               "support for opentracing.TextMapReader and opentracing.TextMapWriter,non-same instance",
+			injectCarrierType:  ot.TextMap,
+			injectCarrier:      newTestTextMapWriter(&shareMap),
+			extractCarrierType: ot.TextMap,
+			extractCarrier:     newTestTextMapReader(&shareMap),
+		},
+		{
+			name:              "inject: format type is HTTPHeaders, but carrier is not HTTPHeadersCarrier",
+			injectCarrierType: ot.HTTPHeaders,
+			injectCarrier:     struct{}{},
+			injectErr:         ot.ErrInvalidCarrier,
+		},
+		{
+			name:               "extract: format type is HTTPHeaders, but carrier is not HTTPHeadersCarrier",
+			injectCarrierType:  ot.HTTPHeaders,
+			injectCarrier:      httpHeader,
+			extractCarrierType: ot.HTTPHeaders,
+			extractCarrier:     struct{}{},
+			extractErr:         ot.ErrInvalidCarrier,
+		},
+		{
+			name:              "inject: format type is TextMap, but carrier is cannot be wrapped into propagation.TextMapCarrier",
+			injectCarrierType: ot.TextMap,
+			injectCarrier:     struct{}{},
+			injectErr:         ot.ErrInvalidCarrier,
+		},
+		{
+			name:               "extract: format type is TextMap, but carrier is cannot be wrapped into propagation.TextMapCarrier",
+			injectCarrierType:  ot.TextMap,
+			injectCarrier:      otTextMap,
+			extractCarrierType: ot.TextMap,
+			extractCarrier:     struct{}{},
+			extractErr:         ot.ErrInvalidCarrier,
+		},
+		{
+			name:              "inject: unsupported format type",
+			injectCarrierType: ot.Binary,
+			injectErr:         ot.ErrUnsupportedFormat,
+		},
+		{
+			name:               "extract: unsupported format type",
+			injectCarrierType:  ot.TextMap,
+			injectCarrier:      otTextMap,
+			extractCarrierType: ot.Binary,
+			extractCarrier:     struct{}{},
+			extractErr:         ot.ErrUnsupportedFormat,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			err := bridge.Inject(newBridgeSpanContext(trace.NewSpanContext(trace.SpanContextConfig{
+				TraceID: [16]byte{byte(1)},
+				SpanID:  [8]byte{byte(2)},
+			}), nil), tc.injectCarrierType, tc.injectCarrier)
+			assert.Equal(t, tc.injectErr, err)
+
+			if tc.injectErr == nil {
+				spanContext, err := bridge.Extract(tc.extractCarrierType, tc.extractCarrier)
+				assert.Equal(t, tc.extractErr, err)
+
+				if tc.extractErr == nil {
+					bsc, ok := spanContext.(*bridgeSpanContext)
+					assert.True(t, ok)
+
+					assert.Equal(t, spanID.String(), bsc.otelSpanContext.SpanID().String())
+					assert.Equal(t, traceID.String(), bsc.otelSpanContext.TraceID().String())
+				}
+			}
+		})
+	}
+}

bridge/opentracing/go.mod

@@ -6,13 +6,17 @@ replace go.opentelemetry.io/otel => ../..
 
 require (
 	github.com/opentracing/opentracing-go v1.2.0
+	github.com/stretchr/testify v1.7.2
 	go.opentelemetry.io/otel v1.7.0
 	go.opentelemetry.io/otel/trace v1.7.0
 )
 
 require (
+	github.com/davecgh/go-spew v1.1.0 // indirect
 	github.com/go-logr/logr v1.2.3 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
 
 replace go.opentelemetry.io/otel/trace => ../../trace

bridge/opentracing/go.sum

@@ -13,8 +13,11 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
-github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.2 h1:4jaiDzPyXQvSd7D0EjG45355tLlV3VOECpq10pLC+8s=
+github.com/stretchr/testify v1.7.2/go.mod h1:R6va5+xMeoiuVRoj+gSkQ7d3FALtqAAGI1FQKckRals=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=