Spring Test Properties with JUnit 5

Question

I'm starting now to use tests with JUnit 5 and Spring Boot. I have a Rest API with controllers, services and repositories and some utils classes that use @value to get properties from my application.properties . I'm not using "profiles" from Spring, just using the default configuration.

My Application Main:

@EnableScheduling
@EnableDiscoveryClient
@ComponentScan
@SpringBootApplication
public class MyRestApiApplication {

    public static void main(String[] args) {
        SpringApplication.run(MyRestApiApplication.class, args);
    }

}

The class that uses @value :

@Component
public class JWTUtils implements Serializable {

    @Value("${jwt.validity}")
    public String JWT_TOKEN_VALIDITY;

    @Value("${jwt.secret}")
    private String secret;

    // There's no constructors in the class.
}

The Main Test class:

@SpringBootTest
class MyRestApiApplicationTests {

    @Test
    void contextLoads() {
    }
}

My Test class that need the propertie:

class JWTUtilsTest {

    JWTUtils jwtUtils;

    @Test
    void getUsernameFromToken() {
        jwtUtils = new JWTUtils();
        assertNotNull(jwtUtils.JWT_TOKEN_VALIDITY);
        String username = jwtUtils.getUsernameFromToken("token-here");
        assertNotNull(username);
        assertEquals(username, "admin");
    }
}

My project's architecture is:

main/
├── java/
│   ├── com.foo.controller/
│   ├── com.foo.model/
│   ├── com.foo.repository/
│   └── com.foo.service/
└── resources/
    ├── application.properties
    ├── banner.txt
    
test/
├── java/
│   ├── com.foo.controller/
│   ├── com.foo.model/
│   ├── com.foo.repository/
│   └── com.foo.service/
└── resources/
    ├── application-test.properties

I tried "@TestPropertySource" and/or "@ActiveProfiles("test")" in my Main Test class but that didn't worked. Also tried with "@RunWith(SpringRunner.class)".

When I run this test, my "secret" value is "null", which should be the value present in my application.properties

I tried putting "@Autowired" in my JWTUtils jwtUtils but it came out null. The @Autowired didn't worked.

Answer 1

1. JWTUtilsTest is not a spring boot test. Therefore no spring boot magic (like injecting configuration values)
2. You are creating the test instance of JWTUtils yourself. To have spring cast its magic you have to let spring create it (eg by annotating with @Autowired and making JWTUtilsTest a spring boot test.