Spring Boot accessing application.properties for JUnit Test

Question

I am trying to access application.properties or application-test.properties from within JUnit inside my Spring Boot application.

I keep seeing different ways to do this on Stack Overflow and only wish to use my AppConfig class (see below).

Am using Spring Boot 1.5.6 RELEASE and Java 1.8

---

Here's the structure to my application:

MyService
    pom.xml
    src
    ├───main
    │   ├───java
    │   │   └───com
    │   │       └───myservice
    │   │           ├───config
    │   │           │       AppConfig.java
    │   │           └───controller
    │   │           │       UserController.java
    │   │           │ 
    │   │           └─── MyServiceApplication.java    
    │   ├───resources
    │   │      application.properties
    └───test
        ├───java
        │     └───com
        │         └───myservice
        │               └───controller
        │                    UserControllerTest.java
        └───resources
                application-test.properties    

---

com.myservice.config.AppConfig:

@Configuration
public class AppConfig {

    @Value("${userDir}")
    private String userDir;

    // Getters & setters omitted for brevity
}

main/resources/application.properties:

server.contextPath=/MyService
server.port=8080

# users dir
userDir=/opt/users

test.resources/application-test.properties

# users dir
userDir=/opt/users

Am able to obtain & parse this dir within my main Spring Boot application, but I get a NullPointerException when I tried to get it from within my JUnit test class getAllUsers() test method:

@RunWith(SpringRunner.class)
@WebMvcTest(UserController.class)
@ContextConfiguration(initializers = ConfigFileApplicationContextInitializer.class)
@ActiveProfiles("test")
public class UserControllerTest {

    @Autowired
    MockMvc mvc;

    @MockBean
    AppConfig config;

    @MockBean
    UserService userService;

    @Test
    public void getAllUsers() throws Exception {
        User users = new User(config.getUserDir());

        // more lines of code
    }
}

---

On Stack Overflow there are multiple ways to do this which I read as:

• That JUnit classes can read application.properties from main/resources/application.properties.
• Using this.class.getClassLoader.getResourceAsStream(...) // Wish to use my AppConfig.class

Question(s):

1. What am I possibly doing wrong, should it just read from the application.properties file or from the test-properties.file?

2. How does one configure the @ActiveProfiles("test"), am I supposed to set this inside the Maven pom.xml somewhere?

3. Do I need to place AppConfig inside a source folder under test/java/com/myservice/config?

Answer 1

You can use @TestPropertySource annotation in your test class.

Just annotate @TestPropertySource("classpath:config/testing.properties") on your test class.

You should be able to read out the property for example with the @Value annotation.

@Value("${fromTest}")
private String fromTest;

your config like this src/main/resources/config/testing.properties

Answer 2

Add the following annotation to your test class:

@TestPropertySource(locations="classpath:application-test.properties")

this should get you working :) please note that you have to import it:

 import org.springframework.test.context.TestPropertySource;