Rename CorrelationContext to Baggage (#1142)

* Rename 'correlation' to 'baggage'

* Rename CorrelationContext progator to Baggage

* Update CHANGELOG

CHANGELOG.md

@@ -30,6 +30,8 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Rename Jaeger tags used for instrumentation library information to reflect changes in OpenTelemetry specification. (#1119)
 - Rename `ProbabilitySampler` to `TraceIDRatioBased` and change semantics to ignore parent span sampling status. (#1115)
 - Move `tools` package under `internal`. (#1141)
+- Move `go.opentelemetry.io/otel/api/correlation` package to `go.opentelemetry.io/otel/api/baggage`. (#1142)
+   The `correlation.CorrelationContext` propagator has been renamed `baggage.Baggage`.  Other exported functions and types are unchanged.
 
 ## [0.11.0] - 2020-08-24
 

api/correlation/correlation_context_propagator.go → api/baggage/baggage_propagator.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package correlation
+package baggage
 
 import (
 	"context"
@@ -25,27 +25,27 @@ import (
 
 // Temporary header name until W3C finalizes format.
 // https://github.com/open-telemetry/opentelemetry-specification/blob/18b2752ebe6c7f0cdd8c7b2bcbdceb0ae3f5ad95/specification/correlationcontext/api.md#header-name
-const correlationContextHeader = "otcorrelations"
+const baggageHeader = "otcorrelations"
 
-// CorrelationContext propagates Key:Values in W3C CorrelationContext
+// Baggage propagates Key:Values in W3C CorrelationContext
 // format.
 // nolint:golint
-type CorrelationContext struct{}
+type Baggage struct{}
 
-var _ propagation.HTTPPropagator = CorrelationContext{}
+var _ propagation.HTTPPropagator = Baggage{}
 
 // DefaultHTTPPropagator returns the default context correlation HTTP
 // propagator.
 func DefaultHTTPPropagator() propagation.HTTPPropagator {
-	return CorrelationContext{}
+	return Baggage{}
 }
 
 // Inject implements HTTPInjector.
-func (CorrelationContext) Inject(ctx context.Context, supplier propagation.HTTPSupplier) {
-	correlationCtx := MapFromContext(ctx)
+func (b Baggage) Inject(ctx context.Context, supplier propagation.HTTPSupplier) {
+	baggageMap := MapFromContext(ctx)
 	firstIter := true
 	var headerValueBuilder strings.Builder
-	correlationCtx.Foreach(func(kv label.KeyValue) bool {
+	baggageMap.Foreach(func(kv label.KeyValue) bool {
 		if !firstIter {
 			headerValueBuilder.WriteRune(',')
 		}
@@ -57,21 +57,21 @@ func (CorrelationContext) Inject(ctx context.Context, supplier propagation.HTTPS
 	})
 	if headerValueBuilder.Len() > 0 {
 		headerString := headerValueBuilder.String()
-		supplier.Set(correlationContextHeader, headerString)
+		supplier.Set(baggageHeader, headerString)
 	}
 }
 
 // Extract implements HTTPExtractor.
-func (CorrelationContext) Extract(ctx context.Context, supplier propagation.HTTPSupplier) context.Context {
-	correlationContext := supplier.Get(correlationContextHeader)
-	if correlationContext == "" {
+func (b Baggage) Extract(ctx context.Context, supplier propagation.HTTPSupplier) context.Context {
+	baggage := supplier.Get(baggageHeader)
+	if baggage == "" {
 		return ctx
 	}
 
-	contextValues := strings.Split(correlationContext, ",")
-	keyValues := make([]label.KeyValue, 0, len(contextValues))
-	for _, contextValue := range contextValues {
-		valueAndProps := strings.Split(contextValue, ";")
+	baggageValues := strings.Split(baggage, ",")
+	keyValues := make([]label.KeyValue, 0, len(baggageValues))
+	for _, baggageValue := range baggageValues {
+		valueAndProps := strings.Split(baggageValue, ";")
 		if len(valueAndProps) < 1 {
 			continue
 		}
@@ -113,6 +113,6 @@ func (CorrelationContext) Extract(ctx context.Context, supplier propagation.HTTP
 }
 
 // GetAllKeys implements HTTPPropagator.
-func (CorrelationContext) GetAllKeys() []string {
-	return []string{correlationContextHeader}
+func (b Baggage) GetAllKeys() []string {
+	return []string{baggageHeader}
 }

api/correlation/correlation_context_propagator_test.go → api/baggage/baggage_propagator_test.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package correlation_test
+package baggage_test
 
 import (
 	"context"
@@ -22,13 +22,13 @@ import (
 
 	"github.com/google/go-cmp/cmp"
 
-	"go.opentelemetry.io/otel/api/correlation"
+	"go.opentelemetry.io/otel/api/baggage"
 	"go.opentelemetry.io/otel/api/propagation"
 	"go.opentelemetry.io/otel/label"
 )
 
-func TestExtractValidDistributedContextFromHTTPReq(t *testing.T) {
-	props := propagation.New(propagation.WithExtractors(correlation.CorrelationContext{}))
+func TestExtractValidBaggageFromHTTPReq(t *testing.T) {
+	props := propagation.New(propagation.WithExtractors(baggage.Baggage{}))
 	tests := []struct {
 		name    string
 		header  string
@@ -91,18 +91,18 @@ func TestExtractValidDistributedContextFromHTTPReq(t *testing.T) {
 
 			ctx := context.Background()
 			ctx = propagation.ExtractHTTP(ctx, props, req.Header)
-			gotCorCtx := correlation.MapFromContext(ctx)
-			wantCorCtx := correlation.NewMap(correlation.MapUpdate{MultiKV: tt.wantKVs})
-			if gotCorCtx.Len() != wantCorCtx.Len() {
+			gotBaggage := baggage.MapFromContext(ctx)
+			wantBaggage := baggage.NewMap(baggage.MapUpdate{MultiKV: tt.wantKVs})
+			if gotBaggage.Len() != wantBaggage.Len() {
 				t.Errorf(
-					"Got and Want CorCtx are not the same size %d != %d",
-					gotCorCtx.Len(),
-					wantCorCtx.Len(),
+					"Got and Want Baggage are not the same size %d != %d",
+					gotBaggage.Len(),
+					wantBaggage.Len(),
 				)
 			}
 			totalDiff := ""
-			wantCorCtx.Foreach(func(keyValue label.KeyValue) bool {
-				val, _ := gotCorCtx.Value(keyValue.Key)
+			wantBaggage.Foreach(func(keyValue label.KeyValue) bool {
+				val, _ := gotBaggage.Value(keyValue.Key)
 				diff := cmp.Diff(keyValue, label.KeyValue{Key: keyValue.Key, Value: val}, cmp.AllowUnexported(label.Value{}))
 				if diff != "" {
 					totalDiff += diff + "\n"
@@ -117,7 +117,7 @@ func TestExtractValidDistributedContextFromHTTPReq(t *testing.T) {
 }
 
 func TestExtractInvalidDistributedContextFromHTTPReq(t *testing.T) {
-	props := propagation.New(propagation.WithExtractors(correlation.CorrelationContext{}))
+	props := propagation.New(propagation.WithExtractors(baggage.Baggage{}))
 	tests := []struct {
 		name   string
 		header string
@@ -150,20 +150,20 @@ func TestExtractInvalidDistributedContextFromHTTPReq(t *testing.T) {
 			req, _ := http.NewRequest("GET", "http://example.com", nil)
 			req.Header.Set("otcorrelations", tt.header)
 
-			ctx := correlation.NewContext(context.Background(), tt.hasKVs...)
-			wantCorCtx := correlation.MapFromContext(ctx)
+			ctx := baggage.NewContext(context.Background(), tt.hasKVs...)
+			wantBaggage := baggage.MapFromContext(ctx)
 			ctx = propagation.ExtractHTTP(ctx, props, req.Header)
-			gotCorCtx := correlation.MapFromContext(ctx)
-			if gotCorCtx.Len() != wantCorCtx.Len() {
+			gotBaggage := baggage.MapFromContext(ctx)
+			if gotBaggage.Len() != wantBaggage.Len() {
 				t.Errorf(
-					"Got and Want CorCtx are not the same size %d != %d",
-					gotCorCtx.Len(),
-					wantCorCtx.Len(),
+					"Got and Want Baggage are not the same size %d != %d",
+					gotBaggage.Len(),
+					wantBaggage.Len(),
 				)
 			}
 			totalDiff := ""
-			wantCorCtx.Foreach(func(keyValue label.KeyValue) bool {
-				val, _ := gotCorCtx.Value(keyValue.Key)
+			wantBaggage.Foreach(func(keyValue label.KeyValue) bool {
+				val, _ := gotBaggage.Value(keyValue.Key)
 				diff := cmp.Diff(keyValue, label.KeyValue{Key: keyValue.Key, Value: val}, cmp.AllowUnexported(label.Value{}))
 				if diff != "" {
 					totalDiff += diff + "\n"
@@ -174,8 +174,8 @@ func TestExtractInvalidDistributedContextFromHTTPReq(t *testing.T) {
 	}
 }
 
-func TestInjectCorrelationContextToHTTPReq(t *testing.T) {
-	propagator := correlation.CorrelationContext{}
+func TestInjectBaggageToHTTPReq(t *testing.T) {
+	propagator := baggage.Baggage{}
 	props := propagation.New(propagation.WithInjectors(propagator))
 	tests := []struct {
 		name         string
@@ -228,7 +228,7 @@ func TestInjectCorrelationContextToHTTPReq(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			req, _ := http.NewRequest("GET", "http://example.com", nil)
-			ctx := correlation.ContextWithMap(context.Background(), correlation.NewMap(correlation.MapUpdate{MultiKV: tt.kvs}))
+			ctx := baggage.ContextWithMap(context.Background(), baggage.NewMap(baggage.MapUpdate{MultiKV: tt.kvs}))
 			propagation.InjectHTTP(ctx, props, req.Header)
 
 			gotHeader := req.Header.Get("otcorrelations")
@@ -250,7 +250,7 @@ func TestInjectCorrelationContextToHTTPReq(t *testing.T) {
 }
 
 func TestTraceContextPropagator_GetAllKeys(t *testing.T) {
-	var propagator correlation.CorrelationContext
+	var propagator baggage.Baggage
 	want := []string{"otcorrelations"}
 	got := propagator.GetAllKeys()
 	if diff := cmp.Diff(got, want); diff != "" {

api/correlation/context.go → api/baggage/context.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package correlation
+package baggage
 
 import (
 	"context"

api/correlation/doc.go → api/baggage/doc.go

@@ -12,5 +12,5 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Package correlation provides types and utilities for correlation features.
-package correlation // import "go.opentelemetry.io/otel/api/correlation"
+// Package baggage provides types and utilities for baggage features.
+package baggage // import "go.opentelemetry.io/otel/api/baggage"

api/correlation/map.go → api/baggage/map.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package correlation
+package baggage
 
 import "go.opentelemetry.io/otel/label"
 

api/correlation/map_test.go → api/baggage/map_test.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package correlation
+package baggage
 
 import (
 	"fmt"

api/global/internal/state.go

@@ -18,7 +18,7 @@ import (
 	"sync"
 	"sync/atomic"
 
-	"go.opentelemetry.io/otel/api/correlation"
+	"go.opentelemetry.io/otel/api/baggage"
 	"go.opentelemetry.io/otel/api/metric"
 	"go.opentelemetry.io/otel/api/propagation"
 	"go.opentelemetry.io/otel/api/trace"
@@ -121,13 +121,13 @@ func defaultPropagatorsValue() *atomic.Value {
 }
 
 // getDefaultPropagators returns a default Propagators, configured
-// with W3C trace and correlation context propagation.
+// with W3C trace and baggage propagation.
 func getDefaultPropagators() propagation.Propagators {
 	tcPropagator := propagators.TraceContext{}
-	ccPropagator := correlation.CorrelationContext{}
+	bagPropagator := baggage.Baggage{}
 	return propagation.New(
-		propagation.WithExtractors(tcPropagator, ccPropagator),
-		propagation.WithInjectors(tcPropagator, ccPropagator),
+		propagation.WithExtractors(tcPropagator, bagPropagator),
+		propagation.WithInjectors(tcPropagator, bagPropagator),
 	)
 }
 

bridge/opentracing/bridge.go

@@ -25,7 +25,7 @@ import (
 	otext "github.com/opentracing/opentracing-go/ext"
 	otlog "github.com/opentracing/opentracing-go/log"
 
-	otelcorrelation "go.opentelemetry.io/otel/api/correlation"
+	otelbaggage "go.opentelemetry.io/otel/api/baggage"
 	otelglobal "go.opentelemetry.io/otel/api/global"
 	otelpropagation "go.opentelemetry.io/otel/api/propagation"
 	oteltrace "go.opentelemetry.io/otel/api/trace"
@@ -38,15 +38,15 @@ import (
 )
 
 type bridgeSpanContext struct {
-	baggageItems    otelcorrelation.Map
+	baggageItems    otelbaggage.Map
 	otelSpanContext oteltrace.SpanContext
 }
 
 var _ ot.SpanContext = &bridgeSpanContext{}
 
 func newBridgeSpanContext(otelSpanContext oteltrace.SpanContext, parentOtSpanContext ot.SpanContext) *bridgeSpanContext {
 	bCtx := &bridgeSpanContext{
-		baggageItems:    otelcorrelation.NewEmptyMap(),
+		baggageItems:    otelbaggage.NewEmptyMap(),
 		otelSpanContext: otelSpanContext,
 	}
 	if parentOtSpanContext != nil {
@@ -66,7 +66,7 @@ func (c *bridgeSpanContext) ForeachBaggageItem(handler func(k, v string) bool) {
 
 func (c *bridgeSpanContext) setBaggageItem(restrictedKey, value string) {
 	crk := http.CanonicalHeaderKey(restrictedKey)
-	c.baggageItems = c.baggageItems.Apply(otelcorrelation.MapUpdate{SingleKV: label.String(crk, value)})
+	c.baggageItems = c.baggageItems.Apply(otelbaggage.MapUpdate{SingleKV: label.String(crk, value)})
 }
 
 func (c *bridgeSpanContext) baggageItem(restrictedKey string) string {
@@ -327,12 +327,12 @@ func (t *BridgeTracer) SetPropagators(propagators otelpropagation.Propagators) {
 }
 
 func (t *BridgeTracer) NewHookedContext(ctx context.Context) context.Context {
-	ctx = otelcorrelation.ContextWithSetHook(ctx, t.correlationSetHook)
-	ctx = otelcorrelation.ContextWithGetHook(ctx, t.correlationGetHook)
+	ctx = otelbaggage.ContextWithSetHook(ctx, t.baggageSetHook)
+	ctx = otelbaggage.ContextWithGetHook(ctx, t.baggageGetHook)
 	return ctx
 }
 
-func (t *BridgeTracer) correlationSetHook(ctx context.Context) context.Context {
+func (t *BridgeTracer) baggageSetHook(ctx context.Context) context.Context {
 	span := ot.SpanFromContext(ctx)
 	if span == nil {
 		t.warningHandler("No active OpenTracing span, can not propagate the baggage items from OpenTelemetry context\n")
@@ -346,16 +346,16 @@ func (t *BridgeTracer) correlationSetHook(ctx context.Context) context.Context {
 	// we clear the context only to avoid calling a get hook
 	// during MapFromContext, but otherwise we don't change the
 	// context, so we don't care about the old hooks.
-	clearCtx, _, _ := otelcorrelation.ContextWithNoHooks(ctx)
-	m := otelcorrelation.MapFromContext(clearCtx)
+	clearCtx, _, _ := otelbaggage.ContextWithNoHooks(ctx)
+	m := otelbaggage.MapFromContext(clearCtx)
 	m.Foreach(func(kv label.KeyValue) bool {
 		bSpan.setBaggageItemOnly(string(kv.Key), kv.Value.Emit())
 		return true
 	})
 	return ctx
 }
 
-func (t *BridgeTracer) correlationGetHook(ctx context.Context, m otelcorrelation.Map) otelcorrelation.Map {
+func (t *BridgeTracer) baggageGetHook(ctx context.Context, m otelbaggage.Map) otelbaggage.Map {
 	span := ot.SpanFromContext(ctx)
 	if span == nil {
 		t.warningHandler("No active OpenTracing span, can not propagate the baggage items from OpenTracing span context\n")
@@ -374,7 +374,7 @@ func (t *BridgeTracer) correlationGetHook(ctx context.Context, m otelcorrelation
 	for k, v := range items {
 		kv = append(kv, label.String(k, v))
 	}
-	return m.Apply(otelcorrelation.MapUpdate{MultiKV: kv})
+	return m.Apply(otelbaggage.MapUpdate{MultiKV: kv})
 }
 
 // StartSpan is a part of the implementation of the OpenTracing Tracer
@@ -613,7 +613,7 @@ func (t *BridgeTracer) Inject(sm ot.SpanContext, format interface{}, carrier int
 		sc:   bridgeSC.otelSpanContext,
 	}
 	ctx := oteltrace.ContextWithSpan(context.Background(), fs)
-	ctx = otelcorrelation.ContextWithMap(ctx, bridgeSC.baggageItems)
+	ctx = otelbaggage.ContextWithMap(ctx, bridgeSC.baggageItems)
 	otelpropagation.InjectHTTP(ctx, t.getPropagators(), header)
 	return nil
 }
@@ -632,7 +632,7 @@ func (t *BridgeTracer) Extract(format interface{}, carrier interface{}) (ot.Span
 	}
 	header := http.Header(hhcarrier)
 	ctx := otelpropagation.ExtractHTTP(context.Background(), t.getPropagators(), header)
-	baggage := otelcorrelation.MapFromContext(ctx)
+	baggage := otelbaggage.MapFromContext(ctx)
 	otelSC, _, _ := otelparent.GetSpanContextAndLinks(ctx, false)
 	bridgeSC := &bridgeSpanContext{
 		baggageItems:    baggage,