server: Add support for B3 headers via JAEGER_PROPAGATION (#1456)

This will provide compatibility with istio.

Closes #1447

docs/config.yaml

@@ -407,6 +407,8 @@ tracing:
     jaeger:
       # The address of the jaeger-agent where spans should be sent to
       local_agent_address: 127.0.0.1:6831
+      # The tracing header format
+      propagation: jaeger
       sampling:
         # The type of the sampler you want to use. Supports:
         # - const

driver/configuration/provider_viper.go

@@ -10,6 +10,7 @@ import (
 	"github.com/spf13/viper"
 
 	"github.com/ory/x/corsx"
+	"github.com/ory/x/stringsx"
 
 	"github.com/sirupsen/logrus"
 
@@ -251,6 +252,10 @@ func (v *ViperProvider) TracingJaegerConfig() *tracing.JaegerConfig {
 		SamplerType:        viperx.GetString(v.l, "tracing.providers.jaeger.sampling.type", "const", "TRACING_PROVIDER_JAEGER_SAMPLING_TYPE"),
 		SamplerValue:       viperx.GetFloat64(v.l, "tracing.providers.jaeger.sampling.value", float64(1), "TRACING_PROVIDER_JAEGER_SAMPLING_VALUE"),
 		SamplerServerURL:   viperx.GetString(v.l, "tracing.providers.jaeger.sampling.server_url", "", "TRACING_PROVIDER_JAEGER_SAMPLING_SERVER_URL"),
+		Propagation: stringsx.Coalesce(
+			viper.GetString("JAEGER_PROPAGATION"), // Standard Jaeger client config
+			viperx.GetString(v.l, "tracing.providers.jaeger.propagation", "", "TRACING_PROVIDER_JAEGER_PROPAGATION"),
+		),
 	}
 }
 

tracing/tracer.go

@@ -8,6 +8,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	jeagerConf "github.com/uber/jaeger-client-go/config"
+	"github.com/uber/jaeger-client-go/zipkin"
 )
 
 type Tracer struct {
@@ -25,6 +26,7 @@ type JaegerConfig struct {
 	SamplerType        string
 	SamplerValue       float64
 	SamplerServerUrl   string
+	Propagation        string
 }
 
 func (t *Tracer) Setup() error {
@@ -52,8 +54,21 @@ func (t *Tracer) Setup() error {
 			jc.Reporter.LocalAgentHostPort = t.JaegerConfig.LocalAgentHostPort
 		}
 
+		var configs []jeagerConf.Option
+
+		// This works in other jaeger clients, but is not part of jaeger-client-go
+		if t.JaegerConfig.Propagation == "b3" {
+			zipkinPropagator := zipkin.NewZipkinB3HTTPHeaderPropagator()
+			configs = append(
+				configs,
+				jeagerConf.Injector(opentracing.HTTPHeaders, zipkinPropagator),
+				jeagerConf.Extractor(opentracing.HTTPHeaders, zipkinPropagator),
+			)
+		}
+
 		closer, err := jc.InitGlobalTracer(
 			t.ServiceName,
+			configs...,
 		)
 
 		if err != nil {
@@ -119,6 +134,10 @@ func HelpMessage() string {
 
 	Example: TRACING_PROVIDER_JAEGER_LOCAL_AGENT_ADDRESS=127.0.0.1:6831
 
+- TRACING_PROVIDER_JAEGER_PROPAGATION: The tracing header propagation format. Defaults to jaeger.
+
+	Example: TRACING_PROVIDER_JAEGER_PROPAGATION=b3
+
 - TRACING_SERVICE_NAME: Specifies the service name to use on the tracer.
 
 	Default: ORY Hydra