Hystrix Demonstration Application, applies the Hystrix Circuit Breaker logic to example endpoints. Failures are baked into these example endpoints in order to demonstrate circuit breaker behaivor.

#How To Use This is a simple example of a hystrix enabled Java Spring application. To properly use this - import into STS Eclipse as a Maven project, and run the com.example.config.AppConfig.java as a Spring Boot Project.

This app is a headless service that has the following endpoints:

Note: random 500 errors are produced, so keep executing to get valid results.

http://{hostname}/api/payloads - GET

returns a ResponseEntity with a list of a sample JSON payload and the proper http code,

http://{hostname}/api/payloads/hystrix - GET

returns a ResponseEntity with a list of a sample JSON payload and the proper http code from hystrix enabled commands

http://{hostname}/api/payloads/fail - GET

returns a ResponseEntity with a list of a sample JSON payload and the proper http code from normal service endpoints desinged to fail

http://{hostname}/api/payloads/fail/hystrix - GET

returns a ResponseEntity with a list of a sample JSON payload and the proper http code from hystrix enabled command endpoints desinged to fail

#How to Test

All of these endpoints can be tested from postman (a google chrome app) to see the sample returns. To help ensure that failures are seen, these service are very unreliable. At random intervals every service throw an exception. To see how these behave it is most easily illustrated by having your Spring service console open so you can read the application logs on your screen, then right next to that (or on another monitor if you have one) exercise the endpoints in postman. Send several messages to each endpoint over and over again by clicking multiple times. This will illustrate how normal failures would appear and how hystrix failures would appear.

This app also has a test project that has a single MockMVC test that can be run as a jUnit test that will spit out logs that demonstrate the different behaviors and messaging that these implementations report.

#How to see metrics The hystrix stream and health endpoints are exposed for this app and can be accessed via the following endpoints:

http://{hostname}/api/health

http://{hostname}/api/hystrix.stream

These can also be used in tandem with a hystrix dashboard to visualize the data and status of the app. The repo for Hystrix Dashboard is:

https://github.com/spring-cloud-samples/hystrix-dashboard.git

#Disclaimer This project should not be used in production.

This project does not conform to pure rest standards.

This is a contrived project with contrived returns, don't take it too seriously.

#More Information

If you want more - please see the following links:

https://github.com/Netflix/Hystrix

http://cloud.spring.io/spring-cloud-netflix/spring-cloud-netflix.html

https://github.com/Netflix/Hystrix/tree/master/hystrix-contrib/hystrix-javanica

https://keyholesoftware.com/2016/02/01/hystrix-to-prevent-hysterix/