Override a single @Configuration class on every spring boot @Test

Question

On my spring boot application I want to override just one of my @Configuration classes with a test configuration (in particular my @EnableAuthorizationServer @Configuration class), on all of my tests.

So far after an overview of spring boot testing features and spring integration testing features no straightforward solution has surfaced:

• @TestConfiguration: It's for extending, not overriding;
• @ContextConfiguration(classes=…​) and @SpringApplicationConfiguration(classes =…​) let me override the whole config, not just the one class;
• An inner @Configuration class inside a @Test is suggested to override the default configuration, but no example is provided;

Any suggestions?

Answer 1

Inner test configuration

Example of an inner @Configuration for your test:

@RunWith(SpringRunner.class) @SpringBootTest public class SomeTest {      @Configuration     static class ContextConfiguration {         @Bean         @Primary //may omit this if this is the only SomeBean defined/visible         public SomeBean someBean () {             return new SomeBean();         }     }      @Autowired     private SomeBean someBean;      @Test     public void testMethod() {         // test     } } 

Reusable test configuration

If you wish to reuse the Test Configuration for multiple tests, you may define a standalone Configuration class with a Spring Profile @Profile("test"). Then, have your test class activate the profile with @ActiveProfiles("test"). See complete code:

@RunWith(SpringRunner.class) @SpringBootTests @ActiveProfiles("test") public class SomeTest {      @Autowired     private SomeBean someBean;      @Test     public void testMethod() {         // test     } }  @Configuration @Profile("test") public class TestConfiguration {     @Bean     @Primary //may omit this if this is the only SomeBean defined/visible     public SomeBean someBean() {         return new SomeBean();     } } 

@Primary

The @Primary annotation on the bean definition is to ensure that this one will have priority if more than one are found.

Answer 2

You should use spring boot profiles:

1. Annotate your test configuration with @Profile("test").
2. Annotate your production configuration with @Profile("production").
3. Set production profile in your properties file: spring.profiles.active=production.
4. Set test profile in your test class with @Profile("test").

So when your application starts it will use "production" class and when test stars it will use "test" class.

If you use inner/nested @Configuration class it will be be used instead of a your application’s primary configuration.