Exclude Spring Cloud Config Server from Spring boot unit test

user3139545 :

Given I have the following 3 Beans:

@Component
public class ServiceConfig {
    // This value is only available from the Spring Cloud Config Server
    @Value("${example.property}")
    private String exampleProperty;

    public String getExampleProperty() {
        return exampleProperty;
    }
}

@Component
public class S1 {
    int i = 1;
}

@Component
public class S2 {

    @Autowired
    S1 s1;

}

I want to be able to run the following test:

@RunWith(SpringRunner.class)
@SpringBootTest
public class S2Test {

    @Autowired
    S2 s;

    @Test
    public void t2() {
        System.out.println(s.s1.i);
    }

}

The issue I have is that since I want to test the S2 class in isolation and since it uses @Autowired I must have a Spring context in my test, however when the Spring context is started it tries to create all 3 beans which includes the bean with @Value. Since this value is only available from Spring Cloud Config Server the context will fail to be created giving the error: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'serviceConfig': Injection of autowired dependencies failed; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'example.property' in string value "${example.property}".

My Question is: How are properties read from Spring Cloud Config Server handled in the application when unit tests are run, observe in my test i dont even care about the config so I dont want to explicitly have to set a value in my test just for the context to be started?

Artur Czopek :

There is some options.

You can create test profile. Then, you will need to create application-test.yml or application-test.properties file. There, you can set the same value for example.property. There, if you want to start some tests with test profile, you can add to your test class @ActiveProfiles("test") annotation. For these tests, test would be started.
You can set default value for example.property by typing @Value("${example.property:SomeDefaultValue}"). SomeDefaultValue will be inserted if property not found.