Spring Cloud OpenFeign - How can I create a Test Slice?

Question

I have a test for a Feign client and I would like to set up a test slice, like @WebMvcTest, @DataJpaTest, etc.

For example, the following test uses @SpringBootTest and it loads all the application context:

@SpringBootTest
@AutoConfigureWireMock(port = 0)
class AgePredictorFeignClientTest {

    @Autowired
    private AgePredictorFeignClient agePredictorFeignClient;

    @Test
    void getAge() {
        stubFor(get(urlEqualTo("/age-api?name=Henrique"))
                .willReturn(aResponse().withBodyFile("25_years_old.json")
                        .withHeader("Content-Type", "application/json")));

        Integer age = agePredictorFeignClient.getAge("Henrique").getAge();

        assertThat(age).isEqualTo(25);

        verify(getRequestedFor(urlEqualTo("/age-api?name=Henrique")));
    }
}

How could I change this test to load only the context related to Spring Cloud OpenFeign?

The source code for the application with this test is available at https://github.com/henriquels25/openfeign-tests-sample.

Answer 1

Currently there is no out of the box solution to have something like a @FeignTest. However, somebody made a solution for this to be found here. This solution Adds the desired functionality. It also has been proposed to spring-cloud-openfeign.

If you don't want to include the above depedency, I've created an example by manually importing some AutoConfiguration classes to only load necessary functionality. See here for a Feign client under test using this Test configuration

The only down-side of this, is that the wiremock random port can't expanded in time. That's why it has a fixed port.