Spring Boot - Junit unable to load configuration properties in junit test

Question

I have a consumer.properties file with the following contents in src/main/resources, and an accompanying Configuration class that loads and stores the file's contents into class member variables:

//consumer.properties file in src/main/resources:

com.training.consumer.hostname=myhost
com.training.consumer.username=myusername
com.training.consumer.password=mypassword

//ConsumerConfig.java

@Configuration
@PropertySource(
 value= {"classpath:consumer.properties"}
 )
@ConfigurationProperties(prefix="com.training.consumer")
public class ConsumerConfig {
 private String hostname;
 private String username;
 private String password;
 public ConsumerConfig() { }
 public String getHostname() {
 return hostname;
 }
 public void setHostname(String hostname) {
 this.hostname = hostname;
 }
 public String getUsername() {
 return username;
 }
 public void setUsername(String username) {
 this.username = username;
 }
 public String getPassword() {
 return password;
 }
 public void setPassword(String password) {
 this.password = password;
 }
 @Override
 public String toString() {
 return "ConsumerConfig [hostname=" + hostname + ", username=" + username + ", password=" + password + "]";
 }
}

I also have a ConfigsService class that autowires the ConsumerConfig class to retrieve the individual properties:

@Component
public class ConfigsService {
 @Autowired
 ConsumerConfig consumerConfig;
 public ConsumerConfig getConsumerConfig() {
 return consumerConfig;
 }
 public void showConfig() {
 consumerConfig.toString();
 }
 public ConsumerConfig getConfig() {
 return consumerConfig;
 }
}

The properties are loaded up just fine when running the ConfigsService's methods. The problem is in the unit tests, where invoking configService.getConfig().getHostname() returns a null value -- even after having created a src/test/resources directory, and adding my consumer.properties file in it:

@TestPropertySource("classpath:consumer.properties")
public class ConfigsServiceTest {
 @Mock
 ConsumerConfig consumerConfig;
 @InjectMocks
 ConfigsService configService;
 @Before
 public void beforeEach() {
 MockitoAnnotations.initMocks(this);
 }
 @Test
 public void someTest() {
 System.out.println(configService.getConfig().getHostname()); //outputs null here -- wth!
 Assert.assertTrue(true);
 }
}

• James McNee: Hi, are you running this with spring runner, otherwise you will not be spinning up a spring instance during the test?

Answer 1

you are getting null values because of the mock object. I will suggest using spring runner with context configuration which will load properties in the config class and create the bean.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = {ConsumerConfig.class, ConfigsService.class})
@TestPropertySource(locations = "classpath:consumer.properties")
public class ConfigsServiceTest {
 @Autowired
 private ConfigsService configsService;
 @Test
 public void someTest() {
 Assert.assertNotNull(configService.getConfig().getHostname());
 }
}

Answer 2

The error may be because in the ConfigsServiceTest class you are establishing that your ConsumerConfig is a Mock and that is why it is not loading your configuration if you remove that code it should work