Opentracing support

middlewares/tracing/zipkin/zipkin.go

@@ -0,0 +1,40 @@
+package zipkin
+
+import (
+	"io"
+
+	opentracing "github.com/opentracing/opentracing-go"
+	zipkin "github.com/openzipkin/zipkin-go-opentracing"
+)
+
+// Name sets the name of this tracer
+const Name = "zipkin"
+
+// Config provides configuration settings for a zipkin tracer
+type Config struct {
+	HTTPEndpoint string `description:"HTTP Endpoint to report traces to." export:"false"`
+	SameSpan     bool   `description:"Use ZipKin SameSpan RPC style traces." export:"true"`
+	ID128Bit     bool   `description:"Use ZipKin 128 bit root span IDs." export:"true"`
+	Debug        bool   `description:"Enable Zipkin debug." export:"true"`
+}
+
+// Setup sets up the tracer
+func (c *Config) Setup(serviceName string) (opentracing.Tracer, io.Closer, error) {
+	collector, err := zipkin.NewHTTPCollector(c.HTTPEndpoint)
+	recorder := zipkin.NewRecorder(collector, c.Debug, "0.0.0.0:0", serviceName)
+	tracer, err := zipkin.NewTracer(
+		recorder,
+		zipkin.ClientServerSameSpan(c.SameSpan),
+		zipkin.TraceID128Bit(c.ID128Bit),
+		zipkin.DebugMode(c.Debug),
+	)
+
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Without this, child spans are getting the NOOP tracer
+	opentracing.SetGlobalTracer(tracer)
+
+	return tracer, collector, nil
+}