Testing spring-boot @service class

Question

I want to test a @Service class that is normally called with SpringApplication.run().

The service class is:

@Service
@EnableConfigurationProperties(AppProperties.class)
public class MongoService {

    private static final Logger logger = LoggerFactory.getLogger(MongoService.class);

    private MongoClient mongoClient;

    private final AppProperties properties;

    @Autowired
    public MongoService(AppProperties properties) {
        this.properties = properties;
    }

    /**
     * Open connection
     */
    public void openConnection() {

        try {
            mongoClient = new MongoClient(new MongoClientURI(properties.getMongoConnectionString()));
        } catch (Exception e) {
            logger.error("Cannot create connection to Search&Browse database", e);
            throw new BackendException("Cannot create connection to Search&Browse database");
        }
    }

}

When it is called by the controller started with SpringApplication.run(), the MongoService is not null but, when I try from a jUnit it's not working.

So, I'm trying this:

@RunWith(SpringRunner.class)
@SpringBootTest
@ContextConfiguration(classes = AppProperties.class)
public class MongoServiceTest {

    private static final Logger logger = LoggerFactory.getLogger(MongoServiceTest.class);

    @Autowired
    MongoService mongoService;

    @Test
    public void MongoServiceAutowired() {   
        assertNotNull(mongoService);
    }
}

but I'm getting this exception:

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'mypackage.MongoServiceTest': Unsatisfied dependency expressed through field 'mongoService'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'mypackage.services.mongo.MongoService' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

Any clue? Where am I failing?

Solution

I assume that your AppProperties and MongoService is not in the same package

If not you can inject MongoService in that way :

create another class named TestConfiguration

@ComponentScan(basePackageClasses = {
        MongoService.class,
        AppProperties.class
})
@SpringBootApplication
public class TestConfiguration {
    public static void main(String[] args) {
        SpringApplication.run(TestConfiguration.class, args);
    }
}

And in the test just change to :

@RunWith(SpringRunner.class)
@SpringBootTest(classes = TestConfiguration.class) 
public class MongoServiceTest {

    private static final Logger logger = LoggerFactory.getLogger(MongoServiceTest.class);

    @Autowired
    MongoService mongoService;

    @Test
    public void MongoServiceAutowired() {   
        assertNotNull(mongoService);
    }
}