SpringBoot @ServiceConnection is not found when used in an interface implemented by a test class

Using the new @ServiceConnection does not work as I would expect when applied within an interface. It starts the container on a random port rather than my spring defined port.

@DynamicPropertySource does work as I expect.

public interface PostgresContainer {
  @Container
  //  @ServiceConnection
  PostgreSQLContainer<?> postgreSQLContainer = new PostgreSQLContainer<>("postgres:11.1");

  @DynamicPropertySource
  static void initialize(DynamicPropertyRegistry registry) {
    registry.add("spring.datasource.url", postgreSQLContainer::getJdbcUrl);
    registry.add("spring.datasource.username", postgreSQLContainer::getUsername);
    registry.add("spring.datasource.password", postgreSQLContainer::getPassword);
  }
}

Comment From: eddumelendez

It starts the container on a random port rather than my spring defined port.

Can you elaborate more? I think I didn't get it.

Take into account Testcontainers starts containers in random ports and @ServiceConnection maps the properties from the container to spring boot

Comment From: philwebb

Thanks @eddumelendez, I was just writing the same thing!

@therealaleko perhaps you could provide a sample application that shows the problem?

Comment From: therealaleko

Please check the repo here. Thanks! https://github.com/therealaleko/spring_boot_issue_37671

@philwebb @eddumelendez

Comment From: eddumelendez

Thanks! So, the ServiceConnection doesn't work when using interfaces

I think this line here

https://github.com/spring-projects/spring-boot/blob/d310fb6fce1bceed55596cea70186e71eca77655/spring-boot-project/spring-boot-testcontainers/src/main/java/org/springframework/boot/testcontainers/service/connection/ServiceConnectionContextCustomizerFactory.java#L57

should change to MergedAnnotations annotations = MergedAnnotations.from(field, SearchStrategy.TYPE_HIERARCHY);

Comment From: andreasevers

Would it also be possible to add support for inherited interfaces? At the moment the test class has to implement the interface directly, but ideally extending a superclass that implements the interface should work too. I could submit a PR if this is something that could be accepted.

Comment From: philwebb

Good spot @andreasevers, I've refined the search algorithm in e01e4f19129ba671ddcbb388efbb2eb2f7ae7d35

Comment From: andreasevers

Wow, thanks Phil! This is great, using it right away!

Comment From: andreasevers

Could this latest commit also get backported into 3.1.x perhaps?

Comment From: wilkinsona

Good catch, @andreasevers. Thank you. I've done that in https://github.com/spring-projects/spring-boot/commit/fcb75b6a1e61dd1772eda2b8a5e40671314c8ff5.

Comment From: andreasevers

Much appreciated 🙏

Comment From: therealaleko

Thank you!