Define a Reporter and Tracer

To use a tracer, first define a reporter so that trace data can be forwarded to a Zipkin endpoint. We’ll use the URLConnectionSender, and post it to a local Zipkin instance.

You’ll need to add this to every serverice and client:

  • AuthServer.main(…)
  • ChatServer.main(…)
  • ChatClient
AsyncReporter<Span> reporter = AsyncReporter.create(

GrpcTracing tracing = GrpcTracing.create(Tracing.newBuilder()
    .localServiceName("my-service") // MAKE SURE YOU CHANGE THE NAME

Add Server Interceptors

We looked at server interceptors in the previous section. Add the tracing.newServerInterceptor() to every service:

  • AuthServer.main(…)
  • ChatServer.main(…)
final Server server = ServerBuilder.forPort(9091)
            someServiceImpl, tracing.newServerInterceptor()))

Add Client Interceptor

Also, add tracing.newClientInterceptor() to every outbound channels:

  • ChatServer.main(…)
  • ChatClient.initAuthService()
  • ChatClient.initChatServices()
channel = ManagedChannelBuilder…

Start Zipkin Server

A Zipkin server JAR is already in the repository, under the zipkin-server directory. Start the local Zipkin server:

$ cd zipkin-server
$ java -jar zipkin.jar

If you covered everything, restart all the servers and client, login and send a few more messages. Then login into the Zipkin server to see the traces! (Access Zipkin console on http://localhost:9411)