Managed Service for OpenTelemetry:Report Java application data through Zipkin

<dependency>
    <groupId>io.zipkin.brave</groupId>
    <artifactId>brave</artifactId>
    <version>5.4.2</version>
</dependency>

<dependency>
    <groupId>io.zipkin.reporter2</groupId>
    <artifactId>zipkin-sender-okhttp3</artifactId>
    <version>2.7.9</version>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
    <version>2.0.1.RELEASE</version>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-sleuth-core</artifactId>
    <version>2.0.1.RELEASE</version>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-sleuth-zipkin</artifactId>
    <version>2.0.1.RELEASE</version>
</dependency>

spring:
   application:
     # This ends up as the service name in zipkin
     name: sleuthDemo
   zipkin:
     # Uncomment to send to zipkin, replacing 192.168.99.100 with your zipkin IP address
     baseUrl: <endpoint_short>

   sleuth:
     sampler:
       probability: 1.0

   sample:
   zipkin:
     # When enabled=false, traces log to the console. Comment to send to zipkin
     enabled: true

curl http://localhost:3380/traced

/** Configuration for how to send spans to Zipkin */
@Bean Sender sender() {
  return OkHttpSender.create("<endpoint>");
}

/** Configuration for how to buffer spans into messages for Zipkin */
@Bean AsyncReporter<Span> spanReporter() {
  return AsyncReporter.create(sender());
}

/** Controls aspects of tracing such as the name that shows up in the UI */
@Bean Tracing tracing(@Value("${spring.application.name}") String serviceName) {
  return Tracing.newBuilder()
      .localServiceName(serviceName)
      .propagationFactory(ExtraFieldPropagation.newFactory(B3Propagation.FACTORY, "user-name"))
      .currentTraceContext(ThreadLocalCurrentTraceContext.newBuilder()
          .addScopeDecorator(MDCScopeDecorator.create()) // puts trace IDs into logs
          .build()
      )
      .spanReporter(spanReporter()).build();
}

/** decides how to name and tag spans. By default they are named the same as the http method. */
@Bean HttpTracing httpTracing(Tracing tracing) {
  return HttpTracing.create(tracing);
}

/** Creates client spans for http requests */
// We are using a BPP as the Frontend supplies a RestTemplate bean prior to this configuration
@Bean BeanPostProcessor connectionFactoryDecorator(final BeanFactory beanFactory) {
  return new BeanPostProcessor() {
    @Override public Object postProcessBeforeInitialization(Object bean, String beanName) {
      return bean;
    }

    @Override public Object postProcessAfterInitialization(Object bean, String beanName) {
      if (!(bean instanceof RestTemplate)) return bean;

      RestTemplate restTemplate = (RestTemplate) bean;
      List<ClientHttpRequestInterceptor> interceptors =
          new ArrayList<>(restTemplate.getInterceptors());
      interceptors.add(0, getTracingInterceptor());
      restTemplate.setInterceptors(interceptors);
      return bean;
    }

    // Lazy lookup so that the BPP doesn't end up needing to proxy anything.
    ClientHttpRequestInterceptor getTracingInterceptor() {
      return TracingClientHttpRequestInterceptor.create(beanFactory.getBean(HttpTracing.class));
    }
  };
}

/** Creates server spans for http requests */
@Bean Filter tracingFilter(HttpTracing httpTracing) {
  return TracingFilter.create(httpTracing);
}

@Autowired SpanCustomizingAsyncHandlerInterceptor webMvcTracingCustomizer;

/** Decorates server spans with application-defined web tags */
@Override public void addInterceptors(InterceptorRegistry registry) {
  registry.addInterceptor(webMvcTracingCustomizer);
}

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
brave.webmvc.TracingConfiguration

<bean class="zipkin2.reporter.beans.OkHttpSenderFactoryBean">
  <property name="endpoint" value="<endpoint>"/>
</bean>

<!-- allows us to read the service name from spring config -->
<context:property-placeholder/>

<bean class="brave.spring.beans.TracingFactoryBean">
  <property name="localServiceName" value="brave-webmvc3-example"/>
  <property name="spanReporter">
    <bean class="zipkin2.reporter.beans.AsyncReporterFactoryBean">
      <property name="encoder" value="JSON_V2"/>
      <property name="sender" ref="sender"/>
      <!-- wait up to half a second for any in-flight spans on close -->
      <property name="closeTimeout" value="500"/>
    </bean>
  </property>
  <property name="propagationFactory">
    <bean class="brave.propagation.ExtraFieldPropagation" factory-method="newFactory">
      <constructor-arg index="0">
        <util:constant static-field="brave.propagation.B3Propagation.FACTORY"/>
      </constructor-arg>
      <constructor-arg index="1">
        <list>
          <value>user-name</value>
        </list>
      </constructor-arg>
    </bean>
  </property>
  <property name="currentTraceContext">
    <bean class="brave.spring.beans.CurrentTraceContextFactoryBean">
      <property name="scopeDecorators">
        <bean class="brave.context.log4j12.MDCScopeDecorator" factory-method="create"/>
      </property>
    </bean>
  </property>
</bean>

<bean class="brave.spring.beans.HttpTracingFactoryBean">
  <property name="tracing" ref="tracing"/>
</bean>

<bean class="brave.httpclient.TracingHttpClientBuilder"
      factory-method="create">
    <constructor-arg type="brave.http.HttpTracing" ref="httpTracing"/>
  </bean>

  <bean factory-bean="httpClientBuilder" factory-method="build"/>

  <bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
    <property name="interceptors">
      <list>
        <bean class="brave.spring.webmvc.SpanCustomizingHandlerInterceptor"/>
      </list>
    </property>
  </bean>

  <!-- Loads the controller -->
  <context:component-scan base-package="brave.webmvc"/>

<!-- Add the delegate to the standard tracing filter and map it to all paths -->
<filter>
  <filter-name>tracingFilter</filter-name>
  <filter-class>brave.spring.webmvc.DelegatingTracingFilter</filter-class>
</filter>
<filter-mapping>
  <filter-name>tracingFilter</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>

<dependency>
    <groupId>io.zipkin.brave</groupId>
    <artifactId>brave-instrumentation-dubbo-rpc</artifactId>
    <version>5.4.2</version>
</dependency>

<dependency>
    <groupId>io.zipkin.brave</groupId>
    <artifactId>brave-spring-beans</artifactId>
    <version>5.4.2</version>
</dependency>

<dependency>
    <groupId>io.zipkin.brave</groupId>
    <artifactId>brave-context-slf4j</artifactId>
    <version>5.4.2</version>
</dependency>
<dependency>
    <groupId>io.zipkin.reporter2</groupId>
    <artifactId>zipkin-sender-okhttp3</artifactId>
    <version>2.7.9</version>
</dependency>
<dependency>
    <groupId>io.zipkin.brave</groupId>
    <artifactId>brave</artifactId>
    <version>5.4.2</version>
</dependency>

<bean class="zipkin2.reporter.beans.OkHttpSenderFactoryBean">
    <property name="endpoint" value="<endpoint>"/>
</bean>

<bean class="brave.spring.beans.TracingFactoryBean">
    <property name="localServiceName" value="double-provider"/>
    <property name="spanReporter">
        <bean class="zipkin2.reporter.beans.AsyncReporterFactoryBean">
            <property name="sender" ref="sender"/>
            <!-- wait up to half a second for any in-flight spans on close -->
            <property name="closeTimeout" value="500"/>
        </bean>
    </property>
    <property name="currentTraceContext">
        <bean class="brave.spring.beans.CurrentTraceContextFactoryBean">
            <property name="scopeDecorators">
                <bean class="brave.context.slf4j.MDCScopeDecorator" factory-method="create"/>
            </property>
        </bean>
    </property>
</bean>

<!-- Server-side configuration -->
<dubbo:provider filter="tracing" />
<!-- Client-side configuration -->
<dubbo:consumer filter="tracing" />

<dependency>
    <groupId>io.zipkin.brave</groupId>
    <artifactId>brave</artifactId>
    <version>5.4.2</version>
</dependency>
<dependency>
    <groupId>io.zipkin.reporter2</groupId>
    <artifactId>zipkin-sender-okhttp3</artifactId>
    <version>2.7.9</version>
</dependency>

private static final String zipkinEndPoint = "<endpoint>";
...
// Create a sender to transmit spans over HTTP
OkHttpSender sender = OkHttpSender.newBuilder().endpoint(zipkinEndPoint).build();

// Create an async reporter to batch and send spans
Reporter<Span> reporter = AsyncReporter.builder(sender).build();

tracing = Tracing.newBuilder().localServiceName(localServiceName).spanReporter(reporter).build();

private void firstBiz() {
    // Create a root span.
    tracing.tracer().startScopedSpan("parentSpan");
    Span span =  tracing.tracer().currentSpan();
    span.tag("key", "firstBiz");
    secondBiz();
    span.finish();
}

private void secondBiz() {
    tracing.tracer().startScopedSpanWithParent("childSpan", tracing.tracer().currentSpan().context());
    Span childSpan =  tracing.tracer().currentSpan();
    childSpan.tag("key", "secondBiz");
    childSpan.finish();
    System.out.println("end tracing,id:" + childSpan.context().traceIdString());
}

tracer.activeSpan().setTag("http.status_code", "500");

// start a new span representing a client request
oneWaySend = tracer.nextSpan().name(service + "/" + method).kind(CLIENT);
--snip--

// Add the trace context to the request, so it can be propagated in-band
tracing.propagation().injector(Request::addHeader)
                 .inject(oneWaySend.context(), request);

// fire off the request asynchronously, totally dropping any response
request.execute();

// start the client side and flush instead of finish
oneWaySend.start().flush();

// pull the context out of the incoming request
extractor = tracing.propagation().extractor(Request::getHeader);

// convert that context to a span which you can name and add tags to
oneWayReceive = nextSpan(tracer, extractor.extract(request))
    .name("process-request")
    .kind(SERVER)
    ... add tags etc.

// start the server side and flush instead of finish
oneWayReceive.start().flush();

// you should not modify this span anymore as it is complete. However,
// you can create children to represent follow-up work.
next = tracer.newSpan(oneWayReceive.context()).name("step2").start();