I am attempting to use mocks in my integration test and am not having much luck. I am using Spring 3.1.1 and Mockito 1.9.0, and the situation is as follows:
#Component
public class ClassToTest {
#Resource
private Dependency dependency;
}
and
#Component
public class Dependency {
#Resource
private NestedDependency nestedDependency;
}
Now, I want to do an integration test of ClassToTest using Spring's JavaConfig. This is what I have attempted, and it doesn't work:
#Test
#ContextConfiguration
public class ClassToTestIntegrationTest {
#Resource
private ClassToTest classToTest;
#Resource
private Dependency mockDependency;
#Test
public void someTest() {
verify(mockDependency).doStuff();
// other Mockito magic...
}
#Configuration
static class Config {
#Bean
public ClassToTest classToTest() {
return new ClassToTest();
}
#Bean
public Dependency dependency() {
return Mockito.mock(Dependency.class);
}
}
}
I have simplified my setup to make the question easier to understand. In reality I have more dependencies and only want to mock some of them - the others are real, based on config imported from my prod #Configuration classes.
What ends up happening is I get a NoSuchBeanDefinitionException saying that there are no beans of type NestedDependency in the application context. I don't understand this - I thought Spring would receive Mockito's mocked instance of Dependency and not even look at autowiring it. Since this isn't working I end up having to mock my entire object graph - which completely defeats the point of mocking!
Thanks in advance for any help!
I had the same problem and I found another solution.
When Spring instantiate all your beans, it will check if it's a Mockito Mock and in this case, I return false for injection property. To use it, just inject it in a Spring context
Code below:
public class MockBeanFactory extends InstantiationAwareBeanPostProcessorAdapter {
private static final MockUtil mockUtil = new MockUtil();
public MockBeanFactory() {
super();
}
#Override
public boolean postProcessAfterInstantiation(Object bean, String beanName) throws BeansException {
return !mockUtil.isMock(bean);
}
}
What Mockito does when mocking classes is it creates a subclass using cglib having some fancy name like: Dependency$EnhancerByMockito (IIRC). As you probably know, subclasses inherit fields from their parent:
#Component
public class Dependency {
#Resource
private NestedDependency nestedDependency;
}
public class Dependency$EnhancerByMockito extends Dependency{
//...
}
This means Spring still sees the field in base class when presented with mock. What you can do:
Use interfaces, which will cause Mockito to employ dynamic proxies rather than CGLIB-generated classes
Mock NestedDependency - I know it will just cascade the problem one level further
Disable #Resource annotation scanning for tests
Related
I'm using Mockito 3.4.6 in unit test, actually, i have integrated Mockito to my unit test and it works well. While, now i need to optimize some unit test, it's a special dependency injection that the injected object doesn't have no-arg constructor, I tried #Spy but it didn't work.
My Test: I tried 1. #Spy; 2. #Spy with setting instance using = getDtInsightApi(); 3. #Spy with #InjectMocks, all of tests are failed. As Mockito docs said, seems it can't work for this case.
#InjectMocks Mockito will try to inject mocks only either by constructor injection,
setter injection, or property injection in order and as described below.
Also if only use #Spy, it will throw MockitoException:
org.mockito.exceptions.base.MockitoException:
Failed to release mocks
This should not happen unless you are using a third-part mock maker
...
Caused by: org.mockito.exceptions.base.MockitoException: Unable to initialize #Spy annotated field 'api'.
Please ensure that the type 'DtInsightApi' has a no-arg constructor.
...
Caused by: org.mockito.exceptions.base.MockitoException: Please ensure that the type 'DtInsightApi' has a no-arg constructor.
See my pseudocode as below:
configure class:
#Configuration
public class SdkConfig {
#Resource
private EnvironmentContext environmentContext;
#Bean(name = "api")
public DtInsightApi getApi() {
DtInsightApi.ApiBuilder builder = new DtInsightApi.ApiBuilder()
.setServerUrls("sdkUrls")
return builder.buildApi();
}
}
DtInsightApi class with no public no-arg constructor and get instance by its inner class
public class DtInsightApi {
private String[] serverUrls;
DtInsightApi(String[] serverUrls) {
this.serverUrls = serverUrls;
}
// inner class
public static class ApiBuilder {
String[] serverUrls;
public ApiBuilder() {
}
...code...
public DtInsightApi buildApi() {
return new DtInsightApi(this.serverUrls);
}
}
...code...
}
unit test class:
public Test{
#Autowired
private PendingTestService service;
#Spy
private Api api = getDtInsightApi();
#Mock
private MockService mockService;
#Before
public void setUp() throws Exception {
// open mock
MockitoAnnotations.openMocks(this);
// i use doReturn(...).when() for #Spy object
Mockito.doReturn(mockService).when(api)
.getSlbApiClient(MockService.class);
Mockito.when(mockService.addOrUpdate(any(MockDTO.class)))
.thenReturn(BaseObject.getApiResponseWithSuccess());
}
public DtInsightApi getDtInsightApi () {
return new DtInsightApi.ApiBuilder()
.setServerUrls(new String[]{"localhost:8080"})
.buildApi();
}
#Test
public void testUpdate() {
service.update();
}
}
PendingTestService:
#Service
public class PendingTestService{
#Autowired
DtInsightApi api;
public void update() {
// here mockService isn't the object i mocked
MockService mockService = api.getSlbApiClient(MockService.class);
mockService.update();
}
}
Question: How to mock the DI object DtInsightApi which doesn't have no-arg constructor.
After checked Spring docs about unit test, I found a solution using #MockBean.
Spirng docs:https://docs.spring.io/spring-boot/docs/1.5.2.RELEASE/reference/html/boot-features-testing.html
According to Spring docs, you can use #MockBean to mock a bean inside your ApplicationContext, so i can use #MockBean to mock DtInsightApi.
It’s sometimes necessary to mock certain components within your application context when running tests. For example,
you may have a facade over some remote service that’s unavailable during development. Mocking can also be useful when
you want to simulate failures that might be hard to trigger in a real environment.
Spring Boot includes a #MockBean annotation that can be used to define a Mockito mock for a bean inside your ApplicationContext.
You can use the annotation to add new beans, or replace a single existing bean definition. The annotation can be used directly on test classes,
on fields within your test, or on #Configuration classes and fields. When used on a field, the instance of the created mock will also be injected.
Mock beans are automatically reset after each test method.
My Solution: Use #MockBean and BDDMockito.given(...).willReturn(...), use
#Qualifier("api") to specify the bean name because #MockBean injected by class type, if you have same class beans, you need to specify bean name.
My code in test class:
public class Test{
#MockBean
#Qualifier("api")
private DtInsightApi api;
#Mock
private MockService mockService;
#Before
public void setUp() throws Exception {
// open mock
MockitoAnnotations.openMocks(this);
BDDMockito.given(this.api.getSlbApiClient(MockService.class)).willReturn(mockService);
}
#Autowired
private PendingTestService service;
#Test
public void testUpdate() {
service.update();
}
}
Debug the mockService you can see mockService instance is generated by Mockito, mock succeed.
You can also refer to Spring docs example: mock RemoteService in unit test.
import org.junit.*;
import org.junit.runner.*;
import org.springframework.beans.factory.annotation.*;
import org.springframework.boot.test.context.*;
import org.springframework.boot.test.mock.mockito.*;
import org.springframework.test.context.junit4.*;
import static org.assertj.core.api.Assertions.*;
import static org.mockito.BDDMockito.*;
#RunWith(SpringRunner.class)
#SpringBootTest
public class MyTests {
#MockBean
private RemoteService remoteService;
#Autowired
private Reverser reverser;
#Test
public void exampleTest() {
// RemoteService has been injected into the reverser bean
given(this.remoteService.someCall()).willReturn("mock");
String reverse = reverser.reverseSomeCall();
assertThat(reverse).isEqualTo("kcom");
}
}
I am trying to write an integration test that tests class A that has nested dependency injection. So I ultimately I want to inject mock of class C.
I am aware of the annotation #MockBean that is available from Spring Boot 1.4 but my hard requirement is Spring Boot 1.3 with Java 7.
Could someone help me how I can mock nested dependency?
public class A {
#Autowired
private B b;
private void run() {
b.run();
}
}
public class B {
#Autowired
private C c;
private void run() {
c.run();
}
}
public class C {
private void run() {
//some action
}
}
public class Test {
#Autowired
private A a;
#Test
private void runTest() {
a.run();
}
}
Create a Mock bean of the same type in the Test context and mark it as Primary.
Since the #MockBean has been released as of the Spring version 1.4, the best alternative you might use is the Mockito library and its mocking features instead:
C c = Mockito.mock(C.class);
Prefer the constructor injection instead of the setters one. You can pass this mocked class through the constructor.
Alternatively, there is a possibility to use #Profile to distinguish a real bean from the mocked one. Read more at Injecting Mockito Mocks into Spring Beans.
Assume, that I have a test configuration with several Spring beans, that are actually mocked and I want to specify the behavior of those mocks inside JUnit test suite.
#Profile("TestProfile")
#Configuration
#EnableTransactionManagement
#ComponentScan(basePackages = {
"some.cool.package.*"})
public class IntegrationTestConfiguration {
#Bean
#Primary
public Cool cool() {
return Mockito.mock(Cool.class);
}
}
// ...
#RunWith(SpringJUnit4ClassRunner.class)
#SpringBootTest
#ActiveProfiles("TestProfile")
public class CoolIntegrationTest {
private final Cool cool;
#Autowired
public CoolIntegrationTest(Cool cool) {
this.cool = cool;
}
#Test
public void testCoolBehavior {
when(cool.calculateSomeCoolStuff()).thenReturn(42);
// etc
}
}
If I run this test I will get:
java.lang.Exception: Test class should have exactly one public zero-argument constructor
I know the workaround like use Autowired fields in tests, but I wonder if there a way to use Autowired annotation in JUnit tests?
It's not the autowiring that's the problem, it's the no-arg constructor. JUnit test classes should have a single, no argument constructor. To achieve what you are attempting to do, you should do the following:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringBootTest
#ActiveProfiles("TestProfile")
#ContextConfiguration(classes = {IntegrationTestConfiguration.class})
public class CoolIntegrationTest {
#Autowired
private final Cool cool;
#Test
public void testCoolBehavior {
when(cool.calculateSomeCoolStuff()).thenReturn(42);
// etc
}
}
The contextConfiguration annotation tells spring which config to use for the test, and autowiring the field instead of the constructor will allow you to test your spring bean.
To run a test using Spring you have to add #RunWith(SpringRunner.class) and make sure that your class is added to the classpath. There are a few ways to do it. I.e.
Add class to MVC configuration #WebMvcTest({Class1.class, Class2.class}) or use #ContextConfiguration.
But I see your code, I suppose that it would be easier just use #Mock or #MockBean to mock your beans. It will be much easier.
JUnit requires the Test case to have a no-arg constructor, so, since you don't have one, the exception happens before the wiring process.
So Constructor-Autowiring just doesn't work in this case.
So what to do?
There are many approaches:
The easiest one (since you have spring) is taking advantage of #MockBean annotation:
#RunWith(SpringRunner.class)
#SpringBootTest
....
class MyTest {
#MockBean
private Cool cool;
#Test
void testMe() {
assert(cool!= null); // its a mock actually
}
}
Besides args constructor you need to have additional one no-args constructor. Try add it and check if this exception still occurcs.
#Autowired
public CoolIntegrationTest(Cool cool) {
this.cool = cool;
}
public CoolIntegrationTest() {}
I have a spring boot application and some other components which application should interact with. However, in my unit testing I am using just application functionality and I would like to mock outer API calls. I am stuck as I can't find the way to mock case like this:
My start class with main method:
#ComponentScan("com.sample.application")
#SpringBootApplication
public class MyApp implements CommandLineRunner {
#Autowired
private OuterAPI outerAPI;
public static void main(String[] args) {
SpringApplication.run(AdRedirectorMain.class, args);
}
#Override
public void run(String... args) throws Exception {
outerAPI.createInstances();
}
...
}
And here is my test class example:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringBootTest(classes = MyApp.class)
public class MyAppTest {
// any tests
}
I am working with Spring Boot, JUnit, Mockito.
So, I am facing the problem - how could I avoid this method call createInstances() with Mockito, via reflection or in any other way.
Have a look at Mocking and spying beans in the Spring Boot documentation.
You can use #MockBean in your test class to replace an autowired bean with a Mockito mock instance.
You can use #MockBean http://docs.spring.io/spring-boot/docs/current/api/org/springframework/boot/test/mock/mockito/MockBean.html
or you can define an interface that you OuterAPI implements then for your test you provide a dummy implementation that makes a dummy call instead of actual call to the outerAPI.createInstances();
Another option that you have is to have configuration class like this:
#Configuration
#Profile(value = {"yourtest-profile"})
public class TestConfiguration{
#Primary
#Bean
public OuterAPI outerAPI() {
return Mockito.mock(OuterAPI.class);
}
}
and put it under scr/test/java
I'm using Spring annotation based configuration in my Play application.
Controllers and DAOs are Spring beans. Controller and DAO layers are defined with different Spring profiles and each layer could be disabled separately.
I'd like to test controller layer in isolation from DAO layer. I've disabled DAO profile and redefined each of DAO beans as a Mockito mock. From functional point of view it works fine, the only thing I don't like is defining mocks manually like this:
#Configuration
#Import(AppContext.class)
public class TestAppContext {
#Bean
public DaoA getDaoA(){
return mock(DaoA.class);
}
//... all dependencies are re-defined manually
}
Is there a way to define package (like with #ComponentScan annotation)
and get all beans in that package as mocks instead of real objects?
UPD:
I'm running tests with FakeApplication (https://www.playframework.com/documentation/2.0/api/java/play/test/FakeApplication.html), so context is started not in the test level, but inside fake application startup.
public class ControllerTest extends WithApplication {
#Before
public void setUp() throws Exception {
start(fakeApplication(new GlobalSettings(){
private ApplicationContext appContext;
public void onStart(Application app) {
appContext = new AnnotationConfigApplicationContext(TestAppContext.class);
}
#Override
public <A> A getControllerInstance(Class<A> clazz) throws Exception {
return appContext.getBean(clazz);
}
}));
}
...
}
I did it like this because I wan't to make the test more reliable and test how controller works in real environment:
#Test
public void testControllerMethod() {
Result result = route(fakeRequest(GET, "/controller/method"));
assertThat(result).is(...);
}
If the number of dependencies you need to mock is huge, you can also use spring-auto-mock.
#ContextConfiguration(classes = { AutoMockRegistryPostProcessor.class, RestOfClasses.class, ... })
#RunWith(SpringJUnit4ClassRunner.class)
public class YourTest {
...
}
As you are creating the ApplicationContext on your own, you can register the postprocessor programmatically:
public void onStart(Application app) {
appContext = new AnnotationConfigApplicationContext(TestAppContext.class);
appContext.getBeanFactory().addBeanPostProcessor(new AutoMockRegistryPostProcessor())
}
Mark your unit-test with #RunWith(SpringJUnit4ClassRunner.class)
Mark your tested class as #InjectMock
Mark you Dao class as #Mock
Make use of Mockito in your project