Spring Cloud Netflix provides easy way of routing using Zuul proxy. It has a feature of circuit breaker in case of heavy load. Though underlying Hystrix provides a fallback, till recently Zuul didn't provide same. Zuul implemented this functionality in Camden SR2. Documentation for using Zuul Fallback is available here.
If you have multiple Zuul routes in your application, it will be cumbersome to write multiple fallback providers. GenericZuulFallbackProvider.java below can be used to provide a generic fallback in your application. Then you need to provide a bean for each route returning this generic fallback after setting route (and other fields like status code, response body etc). Example of beans are available below in ZuulProxyApplication.java.
There is pending enhancement to provide default Zuul fallback. Below code might be still useful for cases where you need to override only some fields.
