Opentracing support

vendor/github.com/uber/jaeger-client-go/interop.go

@@ -0,0 +1,61 @@
+// Copyright (c) 2016 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package jaeger
+
+import (
+	"github.com/opentracing/opentracing-go"
+)
+
+// TODO this file should not be needed after TChannel PR.
+
+type formatKey int
+
+// SpanContextFormat is a constant used as OpenTracing Format.
+// Requires *SpanContext as carrier.
+// This format is intended for interop with TChannel or other Zipkin-like tracers.
+const SpanContextFormat formatKey = iota
+
+type jaegerTraceContextPropagator struct {
+	tracer *Tracer
+}
+
+func (p *jaegerTraceContextPropagator) Inject(
+	ctx SpanContext,
+	abstractCarrier interface{},
+) error {
+	carrier, ok := abstractCarrier.(*SpanContext)
+	if !ok {
+		return opentracing.ErrInvalidCarrier
+	}
+
+	carrier.CopyFrom(&ctx)
+	return nil
+}
+
+func (p *jaegerTraceContextPropagator) Extract(abstractCarrier interface{}) (SpanContext, error) {
+	carrier, ok := abstractCarrier.(*SpanContext)
+	if !ok {
+		return emptyContext, opentracing.ErrInvalidCarrier
+	}
+	ctx := new(SpanContext)
+	ctx.CopyFrom(carrier)
+	return *ctx, nil
+}