I found the following code.
public class Foo {
#Autowired
private MyService myService = new MyService();
}
Does it mean that Spring would overwrite the instance of myService which is created when Foo is created?
This code makes it possible to use Foo in Junit-context without starting in a springcontext.
Is it okay to do things like that?
No, it's not okay to do things like that. Instead:
#Service
public class Foo {
private MyService myService;
#Autowired
public Foo(MyService myService){
this.myService = myService;
}
}ยด
This way Spring injects your required dependency when constructing the Service. For a JUnit context you just need to provide it yourself, it could be as a real instance or as a mock:
#Test
public void testFoo(){
MyService mockService = mock(MyService.class);
Foo foo = new Foo(mockService);
foo.myMethod();
verify(/*Check that foo has done whatever you want with MyService*/);
}
Adding to above answer, you can also run it using ContextConfig as below if you are using Spring 4
Using SpringBoot, you can create bean using #Bean annotation and then autowire it
class MyTestConfig{
#Bean
public MyService myService(){
return new MyService();
};
}
Run test case with MyTestConfig as contextConfiguration and autowire as
#Autowired
public MyService myService
Related
I'm using spring boot rest API and want to test my service layer. In my service I have autowired few beans and its not through constructor. (I like it that way to keep it short).
In the junit, I have created mocks and for private field which I do want to execute, I have assigned using ReflectionTestUtils.setField. When I debug, the method inside the field is not getting executed which assigned by bean.
Service Class
#Component
public class MyService {
#Autowired
private MyRepository myRepository;
#Autowired
private ResponseMapper responseMapper;
public List<MyObj> getList(String param) throws MyException {
log.info("Getting details");
Optional<List<MyObj>> list = myRepository.findByParam(param);
List<MyObj> data = responseMapper.mapToResponseData(list);
return data;
}
}
Test Class
#RunWith(MockitoJUnitRunner.class)
public class MyServiceTest {
#InjectMocks
private MyService myService;
#Mock
private MyRepository myRepository;
#Mock
private ResponseMapper responseMapper;
#Before
public void setUp() {
ReflectionTestUtils.setField(myService, "responseMapper", responseMapper);
}
#Test
public void getListTest() throws Exception {
when(myRepository.findByParam(anyString()))
.thenReturn(Optional.of(getSampleList()));
List<MyObj> list = myService.getList("param");
assertTrue(list.size() >0);
}
}
This results in Assertion failure and when I debug, the method mapToResponseData in ResponseMapper is not getting executed.
I know I can mock mapToResponseData method also. But I wanted it to execute so I don't have to write another test class for mapper alone.
What am I doing wrong? Is this the right wat to inject bean? And is using constructor in service to inject beans only option?
Is there a way to initialise mocks before they are injected into another component?
To give an example I have following classes:
#Service
SomeService {
#Autowired
public SomeService(SomeConfig config)
}
#Configuration
#Getter
#Setter
public class SomeConfig {
private String someValue;
}
In my test I'm doing the following:
#MockBean
SomeConfig someConfig;
#Autowired
SomeService someService;
The problem is, that the SomeService constructor is already accessing SomeConfig members, before I can even initialise it with when(someConfig.getSomeValue()).thenReturn("something"), resulting in a NullPtrException.
Is there a hook that gets executed before SomeService is instantiated?
You could manually setup your Service in a setup method.
Just make sure to exclude your SomeService from classpath scanning in those tests.
SomeServiceTest {
#MockBean
SomeConfig someConfig;
SomeService someService;
#BeforeEach
public void setup(){
// init mocks
// setup other stuff
someService = new SomeService(someConfig);
}
}
I assume that the SomeService looks like:
#Service
SomeService {
private final SomeConfig config
#Autowired
public SomeService(SomeConfig config) {
this.someConfig = someConfig;
// some logic with config getters
}
}
You should use annotation
#PostConsturct in a separate method and put the usage of config getters there, like:
#PostConstruct
private void postConstruct() {
// some logic with config getters
}
Is it possible to inject a mock service into a prototype bean using the #Autowired constructor? I realize I could switch to setter injection but I would prefer to use the constructor if possible.
#Component
#Scope(value = "prototype")
public class Prototype {
private DependantService dependantService;
#Autowired
public Prototype(DependantService dependantService) {
this.dependantService = dependantService;
}
}
#SpringBootTest
public class TestPrototype {
#Autowired
private ApplicationContext ctx;
#Mock
private DependantService dependantService;
#Test
public void testPrototype() {
// How can I inject the mock service?
ctx.getBean(Prototype.class);
}
}
Turns out there is an overloaded version of the getBean method that accepts arguments. I would downvote my on question if I could.
#SpringBootTest
public class TestPrototype {
#Autowired
private ApplicationContext ctx;
#Mock
private DependantService dependantService;
#Test
public void testPrototype() {
Prototype p = ctx.getBean(Prototype.class, dependantService);
// Test p
}
}
If you want to speed up your unit tests, [and do true isolated unit testing,] I suggest taking a look at the #InjectMocks mockito annotation. #SpringBootTest fires up the Spring container which is pretty cumbersome.
#Controller
public class MyController {
#Inject
private Logger log;
public methodThatNeedsTesting(){
log.info("hey this was called");
}
}
#TestInstance(Lifecycle.PER_CLASS)
#ExtendWith({ MockitoExtension.class })
class MyControllerTest {
#Mock
private Logger log;
#InjectMocks
private MyController myController;
#Test
void test_methodThatNeedsTesting() throws Exception {
myController.methodThatNeedsTesting();
// myController will not throw an NPE above because the log field has been injected with a mock
}
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
I have any issue in my unit test where I have something along the lines of this. The mock injection get overridden on the someService if the blargh function is annotated with Transactional. If I remove the Transactional the mock stays there. From watching the code it appears that Spring lazily loads the services when a function in the service is annotated with transactinal, but eagerly loads the services when it isn't. This overrides the mock I injected.
Is there a better way to do this?
#Component
public class SomeTests
{
#Autowired
private SomeService someService;
#Test
#Transactional
public void test(){
FooBar fooBarMock = mock(FooBar.class);
ReflectionTestUtils.setField(someService, "fooBar", fooBarMock);
}
}
#Service
public class someService
{
#Autowired FooBar foobar;
#Transactional // <-- this causes the mocked item to be overridden
public void blargh()
{
fooBar.doStuff();
}
}
Probably you could try to implement your test in the following way:
#Component
#RunWith(MockitoJUnitRunner.class)
public class SomeTests
{
#Mock private FooBar foobar;
#InjectMocks private final SomeService someService = new SomeService();
#Test
#Transactional
public void test(){
when(fooBar.doStuff()).then....;
someService.blargh() .....
}
}
I could not try it right now as don't have your config and related code. But this is one of the common way to test the service logic.
Use the Spring #Profile functionality - beans can be associated to a certain group, and the group can be activated or deactivated via annotations.
Check this blog post and the documentation for more detailed instructions, this is an example of how to define production services and two groups of mock services:
#Configuration
#Profile("production")
public static class ProductionConfig {
#Bean
public InvoiceService realInvoiceService() {
...
}
...
}
#Configuration
#Profile("testServices")
public static class TestConfiguration {
#Bean
public InvoiceService mockedInvoiceService() {
...
}
...
}
#Configuration
#Profile("otherTestServices")
public static class OtherTestConfiguration {
#Bean
public InvoiceService otherMockedInvoiceService() {
...
}
...
}
And this is how to use them in the tests:
#ActiveProfiles("testServices")
public class MyTest extends SpringContextTestCase {
#Autowired
private MyService mockedService;
// ...
}
#ActiveProfiles("otherTestServices")
public class MyOtherTest extends SpringContextTestCase {
#Autowired
private MyService myOtherMockedService;
// ...
}
I have the exact same problem and I solve it by using Mockito.any() for the arguments
eg:
when(transactionalService.validateProduct(id)).thenReturn("")
=> when(transactionalService.validateProduct(Mockito.any())).thenReturn("")