Hystrix Dashboard not working

Question

I am using REST service in springboot application. I am working on Hystrix to enable metrics. So, I deployed hystrix dashboard war in a tomcat server of version 7. I am able to open the page http://localhost:8080/hystrix-dashboard/. After I added the stream url and clicked on Monitor streams button, It takes me to the monitor page, Where all I can see is the message " Unable to connect to command metrix stream". When I look into the hystrix console, I see the below message repeatedly. PLease help me!

2016-10-04 07:23:28 INFO  com.netflix.turbine.discovery.InstanceObservable$1:289 [InstanceObservable$1] [run]: Hosts up:1, hosts down: 0
2016-10-04 07:23:28 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:460 [InstanceMonitor] [getNextStatsData]: no more data from c
onnection to 138.12.51.246
2016-10-04 07:23:28 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:477 [InstanceMonitor] [retryHostConnection]: Re-initing host
connection: 138.12.51.246 default
2016-10-04 07:23:30 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:460 [InstanceMonitor] [getNextStatsData]: no more data from c
onnection to 138.12.51.246
2016-10-04 07:23:30 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:477 [InstanceMonitor] [retryHostConnection]: Re-initing host
connection: 138.12.51.246 default
2016-10-04 07:23:31 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:460 [InstanceMonitor] [getNextStatsData]: no more data from c
onnection to 138.12.51.246
2016-10-04 07:23:31 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:477 [InstanceMonitor] [retryHostConnection]: Re-initing host
connection: 138.12.51.246 default
2016-10-04 07:23:32 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:460 [InstanceMonitor] [getNextStatsData]: no more data from c
onnection to 138.12.51.246
2016-10-04 07:23:32 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:477 [InstanceMonitor] [retryHostConnection]: Re-initing host
connection: 138.12.51.246 default
2016-10-04 07:23:33 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:460 [InstanceMonitor] [getNextStatsData]: no more data from c
onnection to 138.12.51.246
2016-10-04 07:23:33 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:477 [InstanceMonitor] [retryHostConnection]: Re-initing host
connection: 138.12.51.246 default
2016-10-04 07:23:35 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:460 [InstanceMonitor] [getNextStatsData]: no more data from c
onnection to 138.12.51.246
2016-10-04 07:23:35 INFO  com.netflix.turbine.monitor.instance.InstanceMonitor:477 [InstanceMonitor] [retryHostConnection]: Re-initing host
connection: 138.12.51.246 default
2016-10-04 07:23:36 INFO 

Answer 1

Found the answer.. We need to add MIME type as text/event-stream in the response header. The fix I write here for specific to Springboot integration with Hystrix dashboard. All you need to do is,

1) Add metrics event stream dependency in your pom.xml

<dependency>
    <groupId>com.netflix.hystrix</groupId>
    <artifactId>hystrix-metrics-event-stream</artifactId>
    <version>1.5.5</version>
</dependency>

2) Add new servlet with Bean annotation in your SpringApplication class

@Bean
public ServletRegistrationBean servletRegistration() {
 ServletRegistrationBean registration = new ServletRegistrationBean(new HystrixMetricsStreamServlet(), "/hystrix.stream"); 
 return registration;
}

3) Return the response with response header having text/event-stream MIME type. Even, if you have another content type as application/xml, no matter, you can this new one too.

HttpHeaders resHeaders = new HttpHeaders();
resHeaders.add("Content-Type", "application/xml; charset=utf-8");
resHeaders.add("Content-Type", "text/event-stream; charset=utf-8");
if(!isError){
return new ResponseEntity<String>(responseXml, resHeaders, HttpStatus.OK);
}
else{
return new ResponseEntity<com.test.pack.fault.Error>(error, resHeaders,HttpStatus.CREATED);
    }

4) Download and deploy the Hystrix dashboard war file in Tomcat server of version 7 or more and start the server.

5) Open the dashboard with url, http://localhost:port/hystrix-dashboard

6) In the hystrix home page, add the application url as http://localhost:port/contextPath(if any)/hystrix.stream. Then click add stream buttom and click on monitor stream button. The hystrix.stream is the url mapping that we've have given in servlet registration.