In the previous chapters, we developed microservices and client applications for these microservices using load-balancing RestTemplate, EurekaClient, and DiscoveryClient. This way of client implementation requires a lot of boilerplate code for enabling microservices to communicate with each other. In light of these discussions, we will learn about Feign, which is nothing but a declarative HTTP client developed by Netflix.
In this chapter, we will explore what Feign is and how it works. We will also have a detailed discussion on how Feign can be extended or customized for business needs with a reference implementation for a custom encoder, decoder, Hystrix, and exception handling with unit testing.
We will learn how Feign simplifies the HTTP API clients. We don't need to use a lot of boilerplate code to make the HTTP API clients application...