Random management.server.port gets set to the same value as local.server.port

[gkonupek]

A minimum project to reproduce this issue is available here: https://github.com/gkonupek/SpringBootActuatorIssue

The project is a basic Spring Boot web application with Actuator. A problem occurs in tests when using Spring Boot version 2.1.x. In this case, I'm using version 2.1.3.RELEASE.

In the mentioned project, on branch "master" there is the following situation:

• DemoApplicationTests I'm using @SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT) annotation to run the application on a random, free port.
• In application.properties file, I've specified management.server.port=0 to make Actuator endpoint run on a random, free port as well.
• Furthermore, in DemoApplicationTests:
  • I'm injecting 2 values: serverPort (annotated with @LocalServerPort) and managementPort (annotated with @LocalManagementPort).
  • I've created a simple JUnit 5 test in which I'm checking, that both mentioned ports have a different value (that's my expectation).
  • Notice, that the test is also annotated with @ActiveProfiles("test") - it will be important later.
• The Spring Boot version used in this case is 2.0.5.RELEASE.

In this configuration I expect the test to pass. Indeed, the generated ports are different.

Spring Boot 2.1.x

Now, in the repository there is a second branch named "spring-boot-2.1.x". The only difference between master is that the Spring Boot version has been upgraded to 2.1.3.RELEASE.

Unfortunately, in this configuration the test is failing. Both serverPort and managementPort have the same value.

Role of @ActiveProfiles annotation?

Another interesting case is present on the branch named "without-active-profile". In this case, the Spring Boot version is still 2.1.3.RELEASE. However, I've removed the @ActiveProfiles("test") annotation from DemoApplicationTests. In this case, the test is passing again - the port numbers are different.

The last scenario is actually the workaround, which I've applied to make my application work. Instead of using the annotation I could just import my application-test.properties file manually, by using @TestPropertySource annotation. However, I'd really love to see this issue explained and eventually fixed.

Cheers,
Grzegorz

[wilkinsona]

This sounds like it may be a bug in SpringBootTestRandomPortEnvironmentPostProcessor that was introduced in 2.1 to fix #4424.

[mbhave]

Closing in favor of PR #16108.