Dfyjkt

I am using Brave as part of Spring Slueth (Spring Cloud - Edgware.RELEASE). I have written a Filter that intercept every request and create a Span (tag/name) in Zipkin. For example:

//Imports
import brave.Span;
import brave.Tracer;

@Override
public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException 

 Span someSpan = tracer.nextSpan();
 someSpan.kind(Span.Kind.SERVER);

 someSpan.name("my-test-span");
 someSpan.tag("Env", "Dev");

 //Do some Filter specific operation ......

 someSpan.finish();

Now, I would like to write test cases, but I am not sure how to mock Span or tracer within a Servlet Filter?

POM Snippet:

 <dependency>
 <groupId>org.springframework.cloud</groupId>
 <artifactId>spring-cloud-sleuth</artifactId>
 <version>2.0.3.BUILD-SNAPSHOT</version>
 <type>pom</type>
 <scope>import</scope>
 </dependency>

 <dependency>
 <groupId>org.springframework.cloud</groupId>
 <artifactId>spring-cloud-dependencies</artifactId>
 <version>Edgware.RELEASE</version>
 <type>pom</type>
 <scope>import</scope>
 </dependency>

 </dependencies>
</dependencyManagement>

<dependency>
 <groupId>org.springframework.cloud</groupId>
 <artifactId>spring-cloud-starter-zipkin</artifactId>
</dependency>