Mock embedded objects in integration test - java

Trying to write an integration test for a Spring application. Say i've got a class A which contains a class B object. Class B contains a class C object and I need to mock an object within this class for the integration test - any idea how i go about doing that without passing every object through as a parameter in the constructor?
e.g.
#Service
Class A {
#Autowired
private B b;
public void testA() {
B.testB();
}
}
#Service
Class B {
#Autowired
private C c;
public void testB() {
c.testC();
}
}
#Service
Class C {
//External class pulled in from dependency library
#Autowired
private RestTemplate restTemplate;
public void testC() {
restTemplate.doSomethingInOutsideWorld();
}
}
Integration test:
#RunWith(JUnitParamsRunner.class)
#SpringBootTest
public class MyIt {
#ClassRule
public static final SpringClassRule SPRING_CLASS_RULE = new SpringClassRule();
#Rule
public final SpringMethodRule springMethodRule = new SpringMethodRule();
#Mock
private RestTemplate restTemplate;
#Autowired
private A a;
#InjectMocks
private C c;
#Before
public void setup() {
initMocks(this);
}
#Test
public void test1() throws IOException {
a.testA()
}
}
Doesn't mock the RestTemplate object, it tries to hit the outside world. Any advice on how to resolve this?

Achieve this by using SpringRunner and #MockBean
#RunWith(SpringRunner.class) is used to provide a bridge between Spring Boot test features and JUnit. Whenever we are using any Spring Boot testing features in out JUnit tests, this annotation will be required.
The #SpringBootTest annotation can be used when we need to bootstrap the entire container. The annotation works by creating the ApplicationContext that will be utilized in our tests.
Annotation that can be used to add mocks to a Spring ApplicationContext. Can be used as a class level annotation or on fields in either #Configuration classes, or test classes that are #RunWith the SpringRunner.
#RunWith(SpringRunner.class)
#SpringBootTest
public class MyIt {
#MockBean
private RestTemplate restTemplate;
#Autowired
private A a;
#Before
public void setup() {
initMocks(this);
}
#Test
public void test1() throws IOException {
given(this.restTemplate.doSomethingInOutsideWorld()).willReturn(custom object);
a.testA()
}
}

Related

#Repository instance is null when invoking a method using a #Service instance from a unit test

My goal is to use an in-memory database for these unit tests, and those dependancies are listed as:
implementation("org.springframework.boot:spring-boot-starter-data-jpa")
runtimeOnly("com.h2database:h2")
So that the repository instance actually interacts with a DB, and I dont just mock return values.
The problem is that when I run my unit test, the repository instance inside the service instance is null.
Why is that? Am I missing some annotation on the unit test class to initialise the repository instance?
This is the console output when running my unit test:
null
java.lang.NullPointerException
at com.my.MyService.findAll(MyService.java:20)
at com.my.MyTest.testMy(MyTest.java:23)
My unit test class:
public class MyTest {
#MockBean
MyRepository myRepository;
#Test
void testMy() {
MyService myService = new MyService();
int size = myService.findAll().size();
Assertions.assertEquals(0, size);
}
}
My service class:
#Service
public class MyService {
#Autowired
MyRepository myRepository;
public List<MyEntity> findAll() {
System.out.println(myRepository); // null
return (List<MyEntity>) myRepository.findAll(); // throws NullPointerException
}
#Transactional
public MyEntity create(MyEntity myEntity) {
myRepository.save(myEntity);
return myEntity;
}
}
My repository class:
#Repository
public interface MyRepository extends CrudRepository<MyEntity, Long> {
}
My entity class:
#Entity
public class MyEntity {
#Id
#GeneratedValue
public Long id;
}
Why is that? Am I missing some annotation on the unit test class to initialise the repository instance?
Basically yes :)
You need to initialise a Spring Context by Annotating your Testclass with #SpringBootTest
The other Problem you have is that you create your MyService Object manually.
By doing so SpringBoot has no chance to inject any Bean for you. You can fix this by simply injecting your MyService in your Testclass. Your Code should look something like this:
#SpringBootTest
public class MyTest {
#Autowired
private MyService myService;
#Test
void testMy() {
int size = myService.findAll().size();
assertEquals(0, size);
}
}
To use #MockBean annotation, you have to use SpringRunner to run the test. Use #RunWith Annotation on top of your test class and pass SpringRunner.class.
#RunWith(SpringRunner.class)
public class MyTest {
#MockBean
MyRepository myRepository;
#Test
void testMy() {
MyService myService = new MyService();
int size = myService.findAll().size();
Assertions.assertEquals(0, size);
}
}
The problem here is your service implementation. Using #Autowired to inject the dependency will work when you run the whole app, but it do not allow you to inject a custom dependency when you'll need it, and a good example of this is testing.
Change your service implementation to:
#Service
public class MyService {
private MyRepository myRepository;
public MyService(MyRepository myRepository){
this.myRepository = myRepository;
}
public List<MyEntity> findAll() {
System.out.println(myRepository); // null
return (List<MyEntity>) myRepository.findAll(); // throws NullPointerException
}
#Transactional
public MyEntity create(MyEntity myEntity) {
myRepository.save(myEntity);
return myEntity;
}
}
This constructor will be called by spring. Then change your test to:
public class MyTest {
#Mock
MyRepository myRepository;
#Test
void testMy() {
MyService myService = new MyService(myRepository);
int size = myService.findAll().size();
Assertions.assertEquals(0, size);
}
}
Note I have replaced #MockBean to #Mock as the previous annotation is for injecting a mock bean into the spring context, which is not needed if you're doing unit testing. If you want to boot spring context (which I would not recommend you) you need to configure your test class with #SpringBootTest or some of the other available alternatives. That will convert your test into an integration test.
PD: This test will not work if you don't provide a mock to myRepository.findAll(). Mockito default behaviour is to return null, but you're expecting it to return 0, so you'll need to do something like given(myRepository.findAll()).willReturn(0).
I believe you wish to write an integration test. Here you could remove the MockBean annotation and simply autowire your repository. Also, run with The SpringRunner class.
#RunWith(SpringRunner.class)
public class MyTest {
#Autowired
MyRepository myRepository;
#Autowired
MyService myService
#Test
void testMy() {
int size = myService.findAll().size();
Assertions.assertEquals(0, size);
}
}
This should work

Beans are not Autowired during tests (java.lang.NullPointerException)

my application normally works fine, but when I run tests, or build application by maven, application is shutting down due tests with errors java.lang.NullPointerException. I debugged it and find out my that my beans in service layer are not Autowired and they are null.
Here is my class with tests:
public class CompanyServiceSimpleTest {
private CompanyService companyService;
#Before
public void setUp() {
companyService = new CompanyServiceImpl();
}
// Here is sample test
#Test
public void testNumberOfCompanies() {
Assert.assertEquals(2, companyService.findAll().size());
}
}
companyService is initialized, but beans in it not. Here is CompanyServiceImpl:
#Service
public class CompanyServiceImpl implements CompanyService {
#Autowired
private CompanyRepository companyRepository; // is null
#Autowired
private NotificationService notificationService; // is null
#Override
public List<CompanyDto> findAll() {
List<CompanyEntity> entities = companyRepository.find(0, Integer.MAX_VALUE);
return entities.stream().map(Translations.COMPANY_DOMAIN_TO_DTO).collect(Collectors.toList());
}
// ... some other functions
}
So when is called companyRepository.find() applications crashes. Here is repository class:
#Repository
#Profile("inMemory")
public class CompanyInMemoryRepository implements CompanyRepository {
private final List<CompanyEntity> DATA = new ArrayList<>();
private AtomicLong idGenerator = new AtomicLong(3);
#Override
public List<CompanyEntity> find(int offset, int limit) {
return DATA.subList(offset, Math.min(offset+limit, DATA.size()));
}
// ... some others functions
}
I have set up profile for that service but I had that VM options in Idea:
-Dspring.profiles.active=develpment,inMemory
So it should works.
To make autowiring work it has to be a Spring integration test. You have to anotate your test class with:
#RunWith(SpringJUnit4ClassRunner.class) and #ContextConfiguration(classes = {MyApplicationConfig.class})
If it is a Spring Boot app e.g.:
#RunWith(SpringJUnit4ClassRunner.class) and #SpringBootTest(classes = {MyApp.class, MyApplicationConfig.class}, webEnvironment = SpringBootTest.WebEnvironment.DEFINED_PORT)
More on this topic: http://www.baeldung.com/integration-testing-in-spring and http://www.baeldung.com/spring-boot-testing
You are not configuring Spring in your TestClasses, so it's impossible to inject anything...
Try configurin your class with
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = { "path to your config xml" })
A little example:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = {"classpath:config/applicationContext.xml"})
public class MyTest {
#Autowired
private MyClass myInjectedClass;
#Test
public void someTest() {
assertNotNull(myInjectedClass);
}
}

Injecting mocks with Mockito does not work

I'm using Mockito to test my Spring project, but the #InjectMocks seems not working in injecting a mocked service into another Spring service(bean).
Here is my Spring service that I want to test:
#Service
public class CreateMailboxService {
#Autowired UserInfoService mUserInfoService; // this should be mocked
#Autowired LogicService mLogicService; // this should be autowired by Spring
public void createMailbox() {
// do mething
System.out.println("test 2: " + mUserInfoService.getData());
}
}
And below is the service that I want to mock:
#Service
public class UserInfoService {
public String getData() {
return "original text";
}
}
My test code is here:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = { "file:src/main/webapp/WEB-INF/spring/root-context.xml" })
public class CreateMailboxServiceMockTest {
#Mock
UserInfoService mUserInfoService;
#InjectMocks
#Autowired
CreateMailboxService mCreateMailboxService;
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
}
#Test
public void deleteWithPermission() {
when(mUserInfoService.getData()).thenReturn("mocked text");
System.out.println("test 1: " + mUserInfoService.getData());
mCreateMailboxService.createMailbox();
}
}
but the result would like
test 1: mocked text
test 2: original text // I want this be "mocked text", too
it seems that the CreateMailboxService didn't get the mocked UserInfoService but using Spring's autowired bean.
Why is my #InjectMocks not working?
In my case, I had a similar issue when I worked with JUnit5
#ExtendWith(MockitoExtension.class)
class MyServiceTest {
...
#InjectMocks
MyService underTest;
#Test
void myMethodTest() {
...
}
underTest was null.
The cause of the problem was that I used #Test from JUnit4 package import org.junit.Test; instead JUnit5 import org.junit.jupiter.api.Test;
For those who stumbles on this thread and are running with JUnit 5 you need to replace
#RunWith(SpringJUnit4ClassRunner.class)
with
#ExtendWith(MockitoExtension.class)
#RunWith(JUnitPlatform.class)
Further reading here. Unfortunately there is no hint when executing the test cases with JUnit 5 using the old annotation.
You can create package level setter for mUserInfoService in CreateMailboxService class.
#Service
public class CreateMailboxService {
#Autowired UserInfoService mUserInfoService; // this should be mocked
#Autowired LogicService mLogicService; // this should be autowired by Spring
public void createMailbox() {
// do mething
System.out.println("test 2: " + mUserInfoService.getData());
}
void setUserInfoService(UserInfoService mUserInfoService) {
this.mUserInfoService = mUserInfoService;
}
}
Then, you can inject that mock in the test using the setter.
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = { "file:src/main/webapp/WEB-INF/spring/root-context.xml" })
public class CreateMailboxServiceMockTest {
#Mock
UserInfoService mUserInfoService;
CreateMailboxService mCreateMailboxService;
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
mCreateMailboxService = new CreateMailboxService();
mCreateMailboxService.setUserInfoService(mUserInfoService);
}
...
}
This way you can avoid problems with #InjectMocks and Spring annotations.
If you are trying to use the #Mock annotation for a test that relies directly on Spring injection, you may need to replace #Mock with #MockBean #Inject (both annotations), and #InjectMocks with #Inject. Using your example:
#MockBean
#Inject
UserInfoService mUserInfoService;
#Inject
CreateMailboxService mCreateMailboxService;
I had a pretty similar situation. I am writing it down just in case any reader is going through the same. In my case I found that the problem was that I was setting my injected variable as final in the local class.
Following your example, I had things like this:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = { "file:src/main/webapp/WEB-INF/spring/root-context.xml" })
public class CreateMailboxServiceMockTest {
#Mock
UserInfoService mUserInfoService;
#InjectMocks
CreateMailboxService mCreateMailboxService = new CreateMailboxService(mUserInfoService);
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
}
#Test
public void deleteWithPermission() {
...
}
}
But in this class I had it like this:
#Service
public class CreateMailboxService {
private final UserInfoService mUserInfoService; // it is NOT injecting Mocks just because it is final! (all ok with private)
private final LogicService mLogicService; // it is NOT injecting Mocks just because it is final! (all ok with private)
#Autowired
public CreateMailboxService(UserInfoService mUserInfoService, LogicService mLogicService) {
this.mUserInfoService = mUserInfoService;
this.mLogicService = mLogicService;
}
public void createMailbox() {
...
}
}
Just deleting the final condition, #InjectMocks problem was solved.
For those who are running with JUnit 5 you need to replace the #RunWith(SpringJUnit4ClassRunner.class) with #ExtendWith(MockitoExtension.class).
For further reading take a look here.
there is no need of #Autowired annotation when you inject in the test class. And use the mock for the method to get your mocked response as the way you did for UserInfoService.That will be something like below.
Mockito.when(mCreateMailboxService. getData()).thenReturn("my response");
You can use MockitoJUnitRunner to mock in unit tests.
Use #Mock annotations over classes whose behavior you want to mock.
Use #InjectMocks over the class you are testing.
Its a bad practice to use new and initialize classes (better to go for dependency injection) or to introduce setters for your injections. Using setter injection to set dependencies only for tests is wrong as production code should never be altered for tests.
#RunWith(MockitoJUnitRunner.class)
public class CreateMailboxServiceMockTest {
#Mock
UserInfoService mUserInfoService;
#InjectMocks
CreateMailboxService mCreateMailboxService;
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
}
...
}

Mock object method call using Spring Boot and Mockito

I am trying to write a test for this Java SpringBoot's class:
https://github.com/callistaenterprise/blog-microservices/blob/master/microservices/composite/product-composite-service/src/main/java/se/callista/microservices/composite/product/service/ProductCompositeIntegration.java
Specifically, I am trying to "mock" this method call:
URI uri = util.getServiceUrl("product");
I figured out I should "mock" the ServiceUtils object in order to do this. I tried this using the #Mock and #InjectMocks annotations:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = ProductCompositeServiceApplication.class)
public class ProductCompositeIntegrationTest {
#InjectMocks
#Autowired
private ProductCompositeIntegration productIntegration;
#Autowired
private RestTemplate restTemplate;
#Mock
private ServiceUtils util;
private MockRestServiceServer mockServer;
#Before
public void setUp() {
MockitoAnnotations.initMocks(this);
mockServer = MockRestServiceServer.createServer(restTemplate);
}
#Test
public void myTest() {
Mockito.when(util.getServiceUrl("product")).thenReturn(URI.create("http://localhost:8080/test"));
ResponseEntity<Iterable<Product>> products = productIntegration.getAllProducts();
}
}
But this way it still calls the original ServiceUtils object, and not the "mocked" one. Also tried without the #Autowired annotation at the ProductCompositeIntegration, but this results in a NullPointerException.
What am I doing wrong?
My main class looks like this:
#SpringBootApplication
#EnableCircuitBreaker
#EnableDiscoveryClient
public class ProductCompositeServiceApplication {
public static void main(String[] args) {
SpringApplication.run(ProductCompositeServiceApplication.class, args);
}
}
The ServiceUtils object that I am trying to mock is specified in a class, annotated with Spring's #Component annotation to inject it into the other classes using #Autowired.
After a lot of trial and error I managed to solve this problem.
I dropped the
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = ProductCompositeServiceApplication.class)
annotations aboved the test class.
I marked the class that I was testing with #InjectMocks and the dependencies with #Mock:
public class ProductCompositeIntegrationTest {
#InjectMocks
private ProductCompositeIntegration productIntegration;
#Mock
private ServiceUtils util;
private MockRestServiceServer mockServer;
private RestTemplate restTemplate = new RestTemplate();
#Before
public void init() {
MockitoAnnotations.initMocks(this);
mockServer = MockRestServiceServer.createServer(restTemplate);
productIntegration.setRestTemplate(restTemplate);
}
#Test
public void someTests() {
when(util.getServiceUrl("product")).thenReturn(URI.create("http://localhost:8080/test"));
//Test code...
}
}
I'm not sure if this is the best approach ("the Spring way"), but this worked for me.
This article made it all clear to me: http://rdafbn.blogspot.be/2014/01/testing-spring-components-with-mockito.html
You have to write a FactoryBean like
public class MockitoFactoryBean<T> implements FactoryBean<T> {
private Class<T> classToBeMocked;
public MockitoFactoryBean(Class<T> classToBeMocked) {
this.classToBeMocked = classToBeMocked;
}
#Override
public T getObject() throws Exception {
return Mockito.mock(classToBeMocked);
}
#Override
public Class<?> getObjectType() {
return classToBeMocked;
}
#Override
public boolean isSingleton() {
return true;
}
}
In your test-context.xml you have to add the following lines.
<bean id="serviceUtilMock" class="MockitoFactoryBean">
<constructor-arg value="your.package.ServiceUtil" />
</bean>
If you don't use XML configuration, then you have to add the equivalent to above in your Java configuration.

Spring + Mockito injection not working

I'm new with Spring and Mockito testing. I couldn't find answer to my problem on stackoverflow.
I have the following classes:
#EnableScheduling
#Service
public class ServiceEx {
private Queue<Object> tasks = new ConcurrentLinkedQueue();
public void addItem(Object task) {
tasks.add(task);
}
#Scheduled(fixedRate = 30000)
public void executePendingTask() {
tasks.remove();
}
public void drop() {
tasks.clear();
}
public boolean isEmpty() {
return tasks.isEmpty();
}
}
#Controller
#RequestMapping("/drop")
public class ControllerEx {
private ServiceEx service;
#Inject
public ControllerEx(ServiceEx service) {
this.service = service;
}
#RequestMapping(method = RequestMethod.GET)
public String dropTasks(Model model) {
service.drop();
return "redirect:/home";
}
}
And my testing class looks like :
public class ControllerTest {
#Inject
private ServiceEx service;
#InjectMocks
private ControllerEx controller;
private MockMvc mockMvc;
#Before
public void setUp() throws Exception {
MockitoAnnotations.initMocks(this);
this.mockMvc = MockMvcBuilders.standaloneSetup(controller).build();
}
#Test
public void test() {
service.add(task1);
service.add(task2);
this.mockMvc.perform(get("/drop")).andExpect(status().is3xxRedirection());
assertTrue(service.isEmpty());
}
}
My problem is that service is null in both ControlleEx and ControllerTest and i don't want to mock it. I tried several annotations, but didn't find which one to use.
What have i done wrong?
Looking at your code you seem to be mixing unit tests with integration tests.
MockMvc is usually used to do integration tests starting at the controller level. this means that you need a configured and started applicationContext to successfully use that. If that's what this test class is supposed to do then I don't see the use of Mocks, unless you wire them in the application context, your controller won't use them.
If you want to do integration testing, but want to Mock or stub out certain functionality (which in my opinion should only be done because of dependencies on external systems) you should think about wiring some stubs in your applicationContext for this test instead of trying to use Mockito for this.
Also keep in mind that by default, the applicationContext is re-used to run all your tests, which could mean that stubbing for one test could affect an other.

Categories

Resources