Tracing

In auth-service/pom.xml, you can see the dependencies: 1. Brave instrumentation library provides the client side and server side interceptors to propagate trace ID and Spans. 2. URL Connection Reporter can post trace data to a Zipkin server

 <!-- Tracing -->
<dependency>
  <groupId>io.zipkin.brave</groupId>
  <artifactId>brave-instrumentation-grpc</artifactId>
  <version>4.4.0</version>
</dependency>
<dependency>
  <groupId>io.zipkin.reporter</groupId>
  <artifactId>zipkin-sender-urlconnection</artifactId>
  <version>0.10.0</version>
</dependency>