Opentracing support

middlewares/tracing/jaeger/jaeger.go

@@ -0,0 +1,52 @@
+package jaeger
+
+import (
+	"io"
+
+	"github.com/containous/traefik/log"
+	"github.com/opentracing/opentracing-go"
+	jaegercfg "github.com/uber/jaeger-client-go/config"
+	jaegerlog "github.com/uber/jaeger-client-go/log"
+	jaegermet "github.com/uber/jaeger-lib/metrics"
+)
+
+// Name sets the name of this tracer
+const Name = "jaeger"
+
+// Config provides configuration settings for a jaeger tracer
+type Config struct {
+	SamplingServerURL string  `description:"set the sampling server url." export:"false"`
+	SamplingType      string  `description:"set the sampling type." export:"true"`
+	SamplingParam     float64 `description:"set the sampling parameter." export:"true"`
+}
+
+// Setup sets up the tracer
+func (c *Config) Setup(componentName string) (opentracing.Tracer, io.Closer, error) {
+	jcfg := jaegercfg.Configuration{
+		Sampler: &jaegercfg.SamplerConfig{
+			SamplingServerURL: c.SamplingServerURL,
+			Type:              c.SamplingType,
+			Param:             c.SamplingParam,
+		},
+		Reporter: &jaegercfg.ReporterConfig{
+			LogSpans: true,
+		},
+	}
+
+	jLogger := jaegerlog.StdLogger
+	jMetricsFactory := jaegermet.NullFactory
+
+	// Initialize tracer with a logger and a metrics factory
+	closer, err := jcfg.InitGlobalTracer(
+		componentName,
+		jaegercfg.Logger(jLogger),
+		jaegercfg.Metrics(jMetricsFactory),
+	)
+	if err != nil {
+		log.Warnf("Could not initialize jaeger tracer: %s", err.Error())
+		return nil, nil, err
+	}
+	log.Debugf("jaeger tracer configured", err)
+
+	return opentracing.GlobalTracer(), closer, nil
+}