WireMock integration for Spring-Boot

WireMock is an awesome library for mocking HTTP endpoints in unit tests. However, it can be quite cumbersome to integrate with Spring-Boot: when you manually manage the WireMockServer from within the test, there is hardly a chance to use its random base url during Bean creation. That often results in the weirdest stunts of Spring context configuration in order to somehow inject the mock location. For example, your client under test might use the RestTemplate and you decide to make it a mutable field in order to replace it in your test with an instance that knows the WireMock’s location.

In a perfect world, you would not need to touch your existing context configuration for just injecting a mock. Consider the @MockBean annotation that allows to simply replace an already configured Bean with a mock. This works without a hassle and involves no stunts like defining a new Bean with same type and @Primary annotation or manually replacing an injected instance using a setter.

This library works just like that: It sets up a WireMock server early enough, so that its base url can be injected into the Spring application properties, simply replacing an existing value.

The code can be found on GitHub and the library of course is available from MavenCentral