Merge pull request #141 from openzipkin-contrib/refactor_propagation

refactoring of propagation handling

Author: basvanbeek

.gitignore

@@ -2,17 +2,14 @@ version: v1.0.0.{build}
 
 platform: x64
 
-clone_folder: c:\gopath\src\github.com\openzipkin\zipkin-go
+clone_folder: c:\gopath\src\github.com\openzipkin-contrib\zipkin-go-opentracing
 
 environment:
   GOPATH: c:\gopath
   GO111MODULE: on
   GOFLAGS: -mod=readonly
 
 install:
-  - choco install rabbitmq --ignoredependencies -y
-  - echo %PATH%
-  - echo %GOPATH%
   - set PATH=%GOPATH%\bin;c:\go\bin;%PATH%
   - go version
   - go env

appveyor.yml

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"math/rand"
 	"net/http"
-	"sync"
 	"testing"
 	"time"
 
@@ -19,24 +18,13 @@ import (
 var tags []string
 
 func init() {
+	rand.Seed(time.Now().UnixNano())
 	tags = make([]string, 1000)
 	for j := 0; j < len(tags); j++ {
-		tags[j] = fmt.Sprintf("%d", randomID())
+		tags[j] = fmt.Sprintf("%d", rand.Uint64())
 	}
 }
 
-var (
-	seededIDGen = rand.New(rand.NewSource(time.Now().UnixNano()))
-	// The golang rand generators are *not* intrinsically thread-safe.
-	seededIDLock sync.Mutex
-)
-
-func randomID() uint64 {
-	seededIDLock.Lock()
-	defer seededIDLock.Unlock()
-	return uint64(seededIDGen.Int63())
-}
-
 func executeOps(sp opentracing.Span, numEvent, numTag, numItems int) {
 	for j := 0; j < numEvent; j++ {
 		sp.LogEvent("event")

bench_test.go

@@ -1,7 +1,7 @@
 version: 2
 jobs:
   build:
-    working_directory: /go/src/github.com/openzipkin/zipkin-go
+    working_directory: /go/src/github.com/openzipkin-contrib/zipkin-go-opentracing
     parallelism: 1
     docker:
       - image: circleci/golang

circle.yml

@@ -5,10 +5,7 @@ import (
 )
 
 // SpanContext holds the basic Span metadata.
-type spanContextImpl struct {
-	zipkinContext model.SpanContext
-}
+type SpanContext model.SpanContext
 
 // ForeachBaggageItem belongs to the opentracing.SpanContext interface
-func (c *spanContextImpl) ForeachBaggageItem(handler func(k, v string) bool) {
-}
+func (c SpanContext) ForeachBaggageItem(handler func(k, v string) bool) {}

context.go

@@ -0,0 +1,116 @@
+// Copyright 2019 The OpenZipkin 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 zipkintracer
+
+import (
+	"net/http"
+
+	opentracing "github.com/opentracing/opentracing-go"
+	"github.com/openzipkin/zipkin-go/model"
+	"github.com/openzipkin/zipkin-go/propagation"
+	"github.com/openzipkin/zipkin-go/propagation/b3"
+)
+
+// DelegatingCarrier is a flexible carrier interface which can be implemented
+// by types which have a means of storing the trace metadata and already know
+// how to serialize themselves
+type DelegatingCarrier interface {
+	State() (model.SpanContext, error)
+	SetState(model.SpanContext) error
+}
+
+type textMapPropagator struct {
+	tracer *tracerImpl
+}
+
+func (p *textMapPropagator) Inject(
+	spanContext opentracing.SpanContext,
+	opaqueCarrier interface{},
+) error {
+	sc, ok := spanContext.(SpanContext)
+	if !ok {
+		return opentracing.ErrInvalidSpanContext
+	}
+	// native zipkin-go injector
+	if injector, ok := opaqueCarrier.(propagation.Injector); ok {
+		return injector(model.SpanContext(sc))
+	}
+	// fallback to support native opentracing http carrier
+	if httpCarrier, ok := opaqueCarrier.(opentracing.HTTPHeadersCarrier); ok {
+		req := &http.Request{Header: http.Header(httpCarrier)}
+		switch p.tracer.opts.b3InjectOpt {
+		case B3InjectSingle:
+			return b3.InjectHTTP(req, b3.WithSingleHeaderOnly())(model.SpanContext(sc))
+		case B3InjectBoth:
+			return b3.InjectHTTP(req, b3.WithSingleAndMultiHeader())(model.SpanContext(sc))
+		default:
+			return b3.InjectHTTP(req)(model.SpanContext(sc))
+		}
+	}
+
+	return opentracing.ErrInvalidCarrier
+}
+
+func (p *textMapPropagator) Extract(
+	opaqueCarrier interface{},
+) (opentracing.SpanContext, error) {
+	if extractor, ok := opaqueCarrier.(propagation.Extractor); ok {
+		sc, err := extractor()
+		if sc != nil {
+			return SpanContext(*sc), err
+		}
+		return SpanContext{}, err
+	}
+	if httpCarrier, ok := opaqueCarrier.(opentracing.HTTPHeadersCarrier); ok {
+		req := &http.Request{Header: http.Header(httpCarrier)}
+		sc, err := b3.ExtractHTTP(req)()
+		if sc != nil {
+			return SpanContext(*sc), err
+		}
+		return SpanContext{}, err
+	}
+	return nil, opentracing.ErrUnsupportedFormat
+}
+
+type accessorPropagator struct {
+	tracer *tracerImpl
+}
+
+func (p *accessorPropagator) Inject(
+	spanContext opentracing.SpanContext,
+	opaqueCarrier interface{},
+) error {
+	dc, ok := opaqueCarrier.(DelegatingCarrier)
+	if !ok || dc == nil {
+		return opentracing.ErrInvalidCarrier
+	}
+	sc, ok := spanContext.(SpanContext)
+	if !ok {
+		return opentracing.ErrInvalidSpanContext
+	}
+	return dc.SetState(model.SpanContext(sc))
+}
+
+func (p *accessorPropagator) Extract(
+	opaqueCarrier interface{},
+) (opentracing.SpanContext, error) {
+	dc, ok := opaqueCarrier.(DelegatingCarrier)
+	if !ok || dc == nil {
+		return nil, opentracing.ErrInvalidCarrier
+	}
+
+	sc, err := dc.State()
+	return SpanContext(sc), err
+}