Refactor: move ExtractTraceID functions to tracing package

Signed-off-by: Bryan Boreham <[email protected]>

middleware/http_tracing.go

@@ -6,8 +6,6 @@ import (
 
 	"github.com/opentracing-contrib/go-stdlib/nethttp"
 	"github.com/opentracing/opentracing-go"
-	jaeger "github.com/uber/jaeger-client-go"
-	"golang.org/x/net/context"
 )
 
 // Dummy dependency to enforce that we have a nethttp version newer
@@ -40,32 +38,3 @@ func (t Tracer) Wrap(next http.Handler) http.Handler {
 
 	return nethttp.Middleware(opentracing.GlobalTracer(), next, options...)
 }
-
-// ExtractTraceID extracts the trace id, if any from the context.
-func ExtractTraceID(ctx context.Context) (string, bool) {
-	sp := opentracing.SpanFromContext(ctx)
-	if sp == nil {
-		return "", false
-	}
-	sctx, ok := sp.Context().(jaeger.SpanContext)
-	if !ok {
-		return "", false
-	}
-
-	return sctx.TraceID().String(), true
-}
-
-// ExtractSampledTraceID works like ExtractTraceID but the returned bool is only
-// true if the returned trace id is sampled.
-func ExtractSampledTraceID(ctx context.Context) (string, bool) {
-	sp := opentracing.SpanFromContext(ctx)
-	if sp == nil {
-		return "", false
-	}
-	sctx, ok := sp.Context().(jaeger.SpanContext)
-	if !ok {
-		return "", false
-	}
-
-	return sctx.TraceID().String(), sctx.IsSampled()
-}

middleware/logging.go

@@ -8,6 +8,7 @@ import (
 	"time"
 
 	"github.com/weaveworks/common/logging"
+	"github.com/weaveworks/common/tracing"
 	"github.com/weaveworks/common/user"
 )
 
@@ -21,7 +22,7 @@ type Log struct {
 // logWithRequest information from the request and context as fields.
 func (l Log) logWithRequest(r *http.Request) logging.Interface {
 	localLog := l.Log
-	traceID, ok := ExtractTraceID(r.Context())
+	traceID, ok := tracing.ExtractTraceID(r.Context())
 	if ok {
 		localLog = localLog.WithField("traceID", traceID)
 	}

tracing/tracing.go

@@ -1,9 +1,12 @@
 package tracing
 
 import (
+	"context"
 	"io"
 
+	"github.com/opentracing/opentracing-go"
 	"github.com/pkg/errors"
+	jaeger "github.com/uber/jaeger-client-go"
 	jaegercfg "github.com/uber/jaeger-client-go/config"
 	jaegerprom "github.com/uber/jaeger-lib/metrics/prometheus"
 )
@@ -45,3 +48,32 @@ func NewFromEnv(serviceName string, options ...jaegercfg.Option) (io.Closer, err
 
 	return installJaeger(serviceName, cfg, options...)
 }
+
+// ExtractTraceID extracts the trace id, if any from the context.
+func ExtractTraceID(ctx context.Context) (string, bool) {
+	sp := opentracing.SpanFromContext(ctx)
+	if sp == nil {
+		return "", false
+	}
+	sctx, ok := sp.Context().(jaeger.SpanContext)
+	if !ok {
+		return "", false
+	}
+
+	return sctx.TraceID().String(), true
+}
+
+// ExtractSampledTraceID works like ExtractTraceID but the returned bool is only
+// true if the returned trace id is sampled.
+func ExtractSampledTraceID(ctx context.Context) (string, bool) {
+	sp := opentracing.SpanFromContext(ctx)
+	if sp == nil {
+		return "", false
+	}
+	sctx, ok := sp.Context().(jaeger.SpanContext)
+	if !ok {
+		return "", false
+	}
+
+	return sctx.TraceID().String(), sctx.IsSampled()
+}