We have covered creating a Spring Cloud Hystrix circuit-breaker and the circuit-breaker Pattern for fault tolerance in the distributed application. We created an application using Spring Netflix Hystrix to test both the circuit's open path and the circuit's closed path. We have implemented the client application to consume REST services by using Spring's RestTemplate and also used Spring Cloud's Netflix Feign.

We saw how to customize the default configuration of the Hystrix command and fallback. We also explored error propagation in the Hystrix command.

We created two REST consumer applications, one using RestTempate and another using the Feign client. And finally, we created a Hystrix Dashboard to monitor the metrics of your project. The Turbine dashboard helps to aggregate all the /hystrix.stream endpoints of all the microservices in the distributed system to a combine the /turbine.stream endpoints.

We learned why circuit-breaker implementation is necessary for building distributed systems and how to use the Hystrix library and customize it for business needs. You have also learned to configure the Hystrix Dashboard with data streams from individual services and configure the Turbine dashboard to aggregate the data streams from multiple services.

In the next chapter, we will explore Spring Boot support for testing.