Cannot use custom spring converter in unit test - java

I am using simple converter for converting string to enum. Here is the custom converter:
#Component
public class SessionStateConverter implements Converter<String, UserSessionState> {
#Override
public UserSessionState convert(String source) {
try {
return UserSessionState.valueOf(source.toUpperCase());
} catch (Exception e) {
LOG.debug(String.format("Invalid UserSessionState value was provided: %s", source), e);
return null;
}
}
}
Currently I am using UserSessionState as PathVariable in my rest controller. The implementation works as expected. However when I try to unit test the rest controller it seems that conversion does not work and it does not hit the controller method.
#RunWith(MockitoJUnitRunner.class)
public class MyTest {
private MockMvc mockMvc;
#Mock
private FormattingConversionService conversionService;
#InjectMocks
private MynController controller;
#Before
public void setup() {
conversionService.addConverter(new SessionStateConverter());
mockMvc = MockMvcBuilders.standaloneSetup(controller).setConversionService(conversionService).build();
}
#Test
public void testSetLoginUserState() throws Exception {
mockMvc.perform(post("/api/user/login"));
}
}
In debug mode I get following error:
nested exception is java.lang.IllegalStateException: Cannot convert value of type 'java.lang.String' to required type 'rest.api.UserSessionState': no matching editors or conversion strategy found
In my opinion the mock for conversion service does not work.
Any ideas?

The conversionService is a mock.
So this:
conversionService.addConverter(new SessionStateConverter());
calls addConverter on mock. This does nothing useful for you.
I believe you want to use real FormattingConversionService: to do it you need to remove #Mock annotation from conversionService field and use a real instance of FormattingConversionService instead:
private FormattingConversionService conversionService = new FormattingConversionService();
If you need to track invocations on real objects as you would do on mock check out : #Spy

If anyone uses implements org.springframework.core.convert.converter.Converter<IN,OUT> and if you are getting similar error while using mockMvc, please follow the below method.
#Autowired
YourConverter yourConverter;
/** Basic initialisation before unit test fires. */
#Before
public void setUp() {
FormattingConversionService formattingConversionService=new FormattingConversionService();
formattingConversionService.addConverter(yourConverter); //Here
MockitoAnnotations.initMocks(this);
this.mockMvc = MockMvcBuilders.standaloneSetup(getController())
.setConversionService(formattingConversionService) // Add it to mockito
.build();
}

Related

Initialize Mocks in test before #BeforeStep

I have a custom reader with an #BeforeStep function in order to initialize some data. These data are comming from an external database.
#Component
public class CustomReader implements ItemReader<SomeDTO> {
private RestApiService restApiService;
private SomeDTO someDTO;
#BeforeStep
private void initialize() {
someDTO = restApiService.getData();
}
#Override
public SomeDTO read() {
...
return someDTO
}
}
In my unit test i need to mock the calls to the external database.
#RunWith(SpringRunner.class)
#SpringBootTest(classes = NedBatchApplication.class)
public class CustomReaderTest {
#Autowired
CustomReader customReader;
#Mock
RestApiService restApiService;
#Before
private void setup() {
MockitoAnnotations.initMocks(this);
ReflectionTestUtils.setField(customReader, "restApiService", restApiService);
Mockito.when(restApiService.getData().thenReturn(expectedData);
}
}
The problem i am facing is the #BeforeStep is executed before the #Before from the unit test, when i lauch my Test. So restApiService.getData() returns null instead of expectedData.
Is there a way to achieve what i want or do i need to do it with a different approach ?
After some reflexion with a co-worker he gave me a solution :
#RunWith(SpringRunner.class)
#SpringBootTest(classes = NedBatchApplication.class)
public class CustomReaderTest {
CustomReader customReader;
#Mock
RestApiService restApiService;
#Before
private void setup() {
MockitoAnnotations.initMocks(this);
Mockito.when(restApiService.getData().thenReturn(expectedData);
this.customReader = new CustomReader(restApiService);
}
#Test
public void test() {
customReader.initialize();
(...)
}
}
Are you certain that the BeforeStep is running before the Before annotation (by using logging or similar?).
It's possible your Mockito invocation is not fully correct. Try using Mockito.doReturn(expectedData).when(restApiService).getData() instead.
As an alternative approach, if the RestApiService was autowired in your custom reader, you'd be able to use the #InjectMocks annotation on the custom reader declaration in your test, which would cause the mocked version of your restApiService to be injected to the class during the test.
Usually when using Spring based tests, try to make dependencies like restApiService (the ones you would like to mock) to be spring beans, and then you can instruct spring to create mock and inject into application context during the application context creation with the help of #MockBean annotation:
import org.springframework.boot.test.mock.mockito.MockBean;
#RunWith(SpringRunner.class)
#SpringBootTest(classes = NedBatchApplication.class)
public class CustomReaderTest {
#MockBean
private RestApiService restApiService;
}

Excluding an ApplicationListener #Component in Spring Boot during tests

I am trying to have my test unit up and running, and I have encountered a weird issue. My application uses an ApplicationListener class annotated as a #Component to perform an operation during startup.
During tests I have mocked the service that contains the logic, but I found that even though Mockito's when instructions work well in controller scope, the bean is not initialized for this ApplicationListener class: instead of returning what I define in the test unit, it returns either false or null - depending on the data type returned by each method in the service.
Since I have not found any way to initialize the mocked service from the test unit for the ApplicationListener class, I have decided to exclude it. To do so I have tried different approaches, being the one most often used that of creating a test application context and change its configuration. Unfortunately, nothing I have seen is working - so I am here asking for help. If possible, I would prefer not touching the ApplicationListener class and do all related coding in the test code.
I am interested in any of the two possible solutions, if they can be done:
1.- Get the mocked behaviour during the ApplicationListener execution, but I have read somewhere that this cannot be done
2.- Exclude the #Component from the test unit somehow.
TestUnit.Java:
#RunWith(SpringRunner.class)
#SpringBootTest(classes = TestApplication.class, webEnvironment = WebEnvironment.RANDOM_PORT)
#AutoConfigureMockMvc
public class TestConfigurationService {
private MockMvc mockMvc;
#Autowired
private WebApplicationContext webApplicationContext;
#MockBean
private MockService mockService;
private void initMockBean () throws Exception {
when(mockService.isDoingSomething()).thenReturn(true);
}
#Before
public void setup() throws Exception {
// Spring mock context application setup
this.mockMvc = webAppContextSetup(webApplicationContext).build();
// Initialize ConsulService mock bean
initMockBean ();
}
}
TestApplication.java
#SpringBootApplication
#EnableAutoConfiguration
#ComponentScan(basePackages="my.base.package", excludeFilters = #Filter(type = FilterType.ASSIGNABLE_TYPE, classes = StartupConfiguration.class))
public class TestApplication {
public static void main(String[] args) {
SpringApplication.run(TestApplication.class, args);
}
}
Besides what is shown in the code, I have also tried this annotation in file TestApplication.java:
#SpringBootApplication(exclude={StartupConfiguration.class})
StartupConfiguration.java
#Component
public class StartupConfiguration implements ApplicationListener<ContextRefreshedEvent> {
#Autowired
private ConfigurationService configurationService;
#Override
public void onApplicationEvent(final ContextRefreshedEvent event) {
try {
configurationService.updateConfiguration();
} catch (Exception e) {
throw new RuntimeException ("Error", e);
}
}
}
ConfigurationService.java
public interface ConfigurationService {
public void updateConfiguration () throws Exception;
}
ConfigurationServiceImpl.java
#Service
#Transactional
public class ConfigurationServiceImpl implements ConfigurationService {
#Autowired
private MService mockService;
#Override
public void updateConfiguration() throws Exception {
if (mockService.isDoingSomething()==false)
throw new Exception ("Something went wrong");
}
}
Versions:
Spring Boot 1.5.4.RELEASE,
Java 1.8
You can create mock bean of the same type and mark it with #Primary annotation to replace real bean. You can achieve this by having test such configuration:
#Configuration
#Import(TestApplication.class)
public class TestConfiguration {
#Bean
#Primary
public ConfigurationService configurationService() {
return Mockito.mock(ConfigurationService.class);
}
}
then get this mock in test:
...
public class TestConfigurationService {
...
#Autowired
ConfigurationService configurationService;
#Before
public void setUp() {
when(mockService.isDoingSomething()).thenReturn(true);
}
}
Thanks, araxn1d. Your answer gave me the clue to solve this issue.
I mocked the StartupConfiguration class in TestUnit.java:
#MockBean
private StartupConfiguration startupConfiguration;
Though in this case I was lucky: application listeners don't have returning methods, so they don't need when test configuration. If I had required that some method there returned for example true or a value, this method would not apply.
But at least for application listeners, this is enough.

Mocking Spring bean's method behavior breaks aspects

I searched SO and found bunch of other questions that looked similar but not exactly, so I'll ask another one.
I have Spring application and say I created custom aspect (looking for CatchMe annotation) to log exceptions in a specific way. I want to test the aspect by mocking the behavior of one of my Spring #Service class's method so it throws exception when it is called. Then in another method, annotated with my custom annotation #CatchMe, I call the first method. What I expect to happen is the exception to get logged. Unfortunatelly the exception is thrown but the aspect is not triggered. So how can I make the aspect to get triggered in this test using Mockito?
Note: I've checked those (plus a bunch more):
Unit testing Spring #Around AOP methods
Spring Aspect not triggered in unit test
Spring: cannot inject a mock into class annotated with the #Aspect annotation
but most of them are Controller related and not Service related and I want to test only the service.
The Test
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = {BeanConfig.class})
public class MyServiceTest {
#Autowired
#InjectMocks
private MyService service;
#Mock
private MyServiceDependency serviceDep;
#Before
public void setUp() throws Exception {
MockitoAnnotations.initMocks(this);
ReflectionTestUtils.setField(service, "serviceDep", serviceDep);
}
#Test
public void test() {
when(serviceDep.process()).thenAnswer(new Answer<Object>() {
#Override
public Object answer(InvocationOnMock invocationOnMock) throws Throwable {
throw new Exception("Sample message.");
}
});
service.execute();
}
}
Services
#Service
public class MyService {
#Autowired
private MyServiceDependency serviceDep;
#CatchMe
public void execute() {
serviceDep.process();
}
}
#Service
public class MyServiceDependency {
public Object process() {
// may throw exception here
}
}
Configuration and Aspect
#Configuration
#EnableAspectJAutoProxy
#ComponentScan(basePackages = {"com.example.services"})
public class BeanConfig { .. }
#Aspect
#Component
public class CatchMeAspect {
#Around("#annotation(CatchMe)")
public Object catchMe(final ProceedingJoinPoint pjp) throws Throwable {
try {
pjp.proceed();
} catch (Throwable t) {
// fency log
}
}
}
#Retention(RetentionPolicy.RUNTIME)
#Target(ElementType.METHOD)
public #interface CatchMe {}
EDIT: The functionality works but I want to verify it with the test.
Actually it is working as expected, however you are running in a side effect of proxy based AOP, especially class based proxies in this case.
Currently you are setting the field on the proxy and not on the actual object inside the proxy. Which is what you actually want. To obtain the actual instance use AopTestUtils.getUltimateTargetObject and then use that in the ReflectionTestUtils.setField method.
#Autowired
#InjectMocks
private MyService service;
#Mock
private MyServiceDependency serviceDep;
#Before
public void setUp() throws Exception {
MockitoAnnotations.initMocks(this);
MyService serviceToInject = AopTestUtils.getUltimateTargetObject(service);
ReflectionTestUtils.setField(serviceToInject, "serviceDep", serviceDep);
}
However I think that approach is wrong, when you start messing around like this there is a better way. Simply use Spring to inject the mock. Create a specific #Configuration class for this test case. Make it a internal public static class and for the dependency add a mocked #Bean.
#Configuration
#Import(BeanConfig.class)
public static class TestBeanConfig {
#Bean
public MyServiceDependency myServiceDependency() {
return Mockito.mock(MyServiceDependency.class);
}
}
Now in your test class you can simply #Autowire both beans and not need to use reflection or whatever to set dependencies.
#RunWith(SpringJUnit4ClassRunner.class)
public class MyServiceTest {
#Autowired
private MyService service;
#Autowired
private MyServiceDependency serviceDep;
#Test
public void test() {
when(serviceDep.process()).thenAnswer(new Answer<Object>() {
#Override
public Object answer(InvocationOnMock invocationOnMock) throws Throwable {
throw new Exception("Sample message.");
}
});
service.execute();
}
}
Which will take care of the correct dependencies.
I had the same problem as #nyxz and this is intentional, see https://github.com/spring-projects/spring-boot/issues/7243.
Inspired by #M. Deinum following solution worked for me with Spring Boot 2.3.4.RELEASE and JUnit 5.
We will just provide a mocked bean without #MockedBean
#SpringBootTest
#DirtiesContext(classMode = DirtiesContext.ClassMode.AFTER_EACH_TEST_METHOD)
class MyServiceTest {
#Autowired
private MyService service;
#Test
public void test() {
service.execute();
}
static class TestBeanConfig {
#Bean
#Primary
public MyServiceDependency myServiceDependency() {
MyServiceDependency myServiceDependency = Mockito.mock(MyServiceDependency.class)
// Add behavior of mocked bean here
return myServiceDependency;
}
}
}

Mock class inside REST controller with Mockito

I have a spring-boot application which exposes a REST interface via a controller. This is an example of my controller:
#RestController
public class Controller {
#Autowired
private Processor processor;
#RequestMapping("/magic")
public void handleRequest() {
// process the POST request
processor.process();
}
}
I am trying to write unit tests for this class and I have to mock the processor (since the processing takes very long time and I am trying to avoid this step during testing the controller behavior). Please note, that the provided example is simplified for the sake of this question.
I am trying to use the mockito framework for this task:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = App.class)
#WebAppConfiguration
#ActiveProfiles("test")
public class ControllerTest {
#Autowired
private WebApplicationContext wac;
private MockMvc mockMvc;
#Before
public void setUp() throws Exception {
this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
Processor processor = Mockito.mock(Processor.class);
ReflectionTestUtils.setField(Controller.class, "processor", processor);
}
#Test
public void testControllerEmptyBody() throws Exception {
this.mockMvc.perform(post("/magic")).andExpect(status().isOk());
}
}
However, this fails with
java.lang.IllegalArgumentException: Could not find field [processor] of type [null] on target [class org.company.Controller]
at org.springframework.test.util.ReflectionTestUtils.setField(ReflectionTestUtils.java:112)
...
Could please someone give me a hint, how this mock could be injected in my controller?
Shouldn't you be passing an instance to set the field on, rather than the class, e.g.:
...
#Autowired
private Controller controller;
...
#Before
public void setUp() throws Exception {
...
Processor processor = Mockito.mock(Processor.class);
ReflectionTestUtils.setField(controller, "processor", processor);
}
I think that you can inject directly the mock like:
#InjectMocks
private ProcessorImpl processorMock;
And remove this line:
ReflectionTestUtils.setField(Controller.class, "processor", processor);
See Injection of a mock object into an object to be tested declared as a field in the test does not work using Mockito?
Rework your controller to use constructor injection instead of field injection. This makes the dependency explicit and makes your test setup drastically simpler.
#Before
public void setUp() throws Exception {
this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
Processor processor = Mockito.mock(Processor.class);
//This line should be added to perform mock for Processor.
Mockito.when(processor.process()).thenReturn(<Your returned value>);
//ReflectionTestUtils.setField(Controller.class, "processor", processor);
}
In above put the your returned value for "Your returned value" and in test use this value to verify your output.
You can remove servlet context class in SpringApplicationConfiguration and mock servlet context. There is no need for injection of WebApplicationContext and ReflectionTestUtils.
Basically, your code should look something like this:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = MockServletContext.class)
#WebAppConfiguration
#ActiveProfiles("test")
public class ControllerTest {
#InjectMocks
private MyController controller;
#Mock
private Processor processor;
private MockMvc mockMvc;
#Before
public void setUp() throws Exception {
MockitoAnnotations.initMocks(this);
this.mockMvc = MockMvcBuilders.standaloneSetup(controller).build();
}
#Test
public void testControllerEmptyBody() throws Exception {
when(proessor.process()).thenReturn(<yourValue>);
this.mockMvc.perform(post("/magic")).andExpect(status().isOk());
verify(processor, times(<number of times>)).process();
}
}
Processor will be mocked and mock will be injected into controller.

Injecting #Autowired private field during testing

I have a component setup that is essentially a launcher for an application. It is configured like so:
#Component
public class MyLauncher {
#Autowired
MyService myService;
//other methods
}
MyService is annotated with the #Service Spring annotation and is autowired into my launcher class without any issues.
I would like to write some jUnit test cases for MyLauncher, to do so I started a class like this:
public class MyLauncherTest
private MyLauncher myLauncher = new MyLauncher();
#Test
public void someTest() {
}
}
Can I create a Mock object for MyService and inject it into myLauncher in my test class? I currently don't have a getter or setter in myLauncher as Spring is handling the autowiring. If possible, I'd like to not have to add getters and setters. Can I tell the test case to inject a mock object into the autowired variable using an #Before init method?
If I'm going about this completely wrong, feel free to say that. I'm still new to this. My main goal is to just have some Java code or annotation that puts a mock object in that #Autowired variable without me having to write a setter method or having to use an applicationContext-test.xml file. I would much rather maintain everything for the test cases in the .java file instead of having to maintain a separate application content just for my tests.
I am hoping to use Mockito for the mock objects. In the past I have done this by using org.mockito.Mockito and creating my objects with Mockito.mock(MyClass.class).
You can absolutely inject mocks on MyLauncher in your test. I am sure if you show what mocking framework you are using someone would be quick to provide an answer. With mockito I would look into using #RunWith(MockitoJUnitRunner.class) and using annotations for myLauncher. It would look something like what is below.
#RunWith(MockitoJUnitRunner.class)
public class MyLauncherTest
#InjectMocks
private MyLauncher myLauncher = new MyLauncher();
#Mock
private MyService myService;
#Test
public void someTest() {
}
}
The accepted answer (use MockitoJUnitRunner and #InjectMocks) is great. But if you want something a little more lightweight (no special JUnit runner), and less "magical" (more transparent) especially for occasional use, you could just set the private fields directly using introspection.
If you use Spring, you already have a utility class for this : org.springframework.test.util.ReflectionTestUtils
The use is quite straightforward :
ReflectionTestUtils.setField(myLauncher, "myService", myService);
The first argument is your target bean, the second is the name of the (usually private) field, and the last is the value to inject.
If you don't use Spring, it is quite trivial to implement such a utility method. Here is the code I used before I found this Spring class :
public static void setPrivateField(Object target, String fieldName, Object value){
try{
Field privateField = target.getClass().getDeclaredField(fieldName);
privateField.setAccessible(true);
privateField.set(target, value);
}catch(Exception e){
throw new RuntimeException(e);
}
}
Sometimes you can refactor your #Component to use constructor or setter based injection to setup your testcase (you can and still rely on #Autowired). Now, you can create your test entirely without a mocking framework by implementing test stubs instead (e.g. Martin Fowler's MailServiceStub):
#Component
public class MyLauncher {
private MyService myService;
#Autowired
MyLauncher(MyService myService) {
this.myService = myService;
}
// other methods
}
public class MyServiceStub implements MyService {
// ...
}
public class MyLauncherTest
private MyLauncher myLauncher;
private MyServiceStub myServiceStub;
#Before
public void setUp() {
myServiceStub = new MyServiceStub();
myLauncher = new MyLauncher(myServiceStub);
}
#Test
public void someTest() {
}
}
This technique especially useful if the test and the class under test is located in the same package because then you can use the default, package-private access modifier to prevent other classes from accessing it. Note that you can still have your production code in src/main/java but your tests in src/main/test directories.
If you like Mockito then you will appreciate the MockitoJUnitRunner. It allows you to do "magic" things like #Manuel showed you:
#RunWith(MockitoJUnitRunner.class)
public class MyLauncherTest
#InjectMocks
private MyLauncher myLauncher; // no need to call the constructor
#Mock
private MyService myService;
#Test
public void someTest() {
}
}
Alternatively, you can use the default JUnit runner and call the MockitoAnnotations.initMocks() in a setUp() method to let Mockito initialize the annotated values. You can find more information in the javadoc of #InjectMocks and in a blog post that I have written.
I believe in order to have auto-wiring work on your MyLauncher class (for myService), you will need to let Spring initialize it instead of calling the constructor, by auto-wiring myLauncher. Once that is being auto-wired (and myService is also getting auto-wired), Spring (1.4.0 and up) provides a #MockBean annotation you can put in your test. This will replace a matching single beans in context with a mock of that type. You can then further define what mocking you want, in a #Before method.
public class MyLauncherTest
#MockBean
private MyService myService;
#Autowired
private MyLauncher myLauncher;
#Before
private void setupMockBean() {
doNothing().when(myService).someVoidMethod();
doReturn("Some Value").when(myService).someStringMethod();
}
#Test
public void someTest() {
myLauncher.doSomething();
}
}
Your MyLauncher class can then remain unmodified, and your MyService bean will be a mock whose methods return values as you defined:
#Component
public class MyLauncher {
#Autowired
MyService myService;
public void doSomething() {
myService.someVoidMethod();
myService.someMethodThatCallsSomeStringMethod();
}
//other methods
}
A couple advantages of this over other methods mentioned is that:
You don't need to manually inject myService.
You don't need use the Mockito runner or rules.
I'm a new user for Spring. I found a different solution for this. Using reflection and making public necessary fields and assign mock objects.
This is my auth controller and it has some Autowired private properties.
#RestController
public class AuthController {
#Autowired
private UsersDAOInterface usersDao;
#Autowired
private TokensDAOInterface tokensDao;
#RequestMapping(path = "/auth/getToken", method = RequestMethod.POST)
public #ResponseBody Object getToken(#RequestParam String username,
#RequestParam String password) {
User user = usersDao.getLoginUser(username, password);
if (user == null)
return new ErrorResult("Kullanıcıadı veya şifre hatalı");
Token token = new Token();
token.setTokenId("aergaerg");
token.setUserId(1);
token.setInsertDatetime(new Date());
return token;
}
}
And this is my Junit test for AuthController. I'm making public needed private properties and assign mock objects to them and rock :)
public class AuthControllerTest {
#Test
public void getToken() {
try {
UsersDAO mockUsersDao = mock(UsersDAO.class);
TokensDAO mockTokensDao = mock(TokensDAO.class);
User dummyUser = new User();
dummyUser.setId(10);
dummyUser.setUsername("nixarsoft");
dummyUser.setTopId(0);
when(mockUsersDao.getLoginUser(Matchers.anyString(), Matchers.anyString())) //
.thenReturn(dummyUser);
AuthController ctrl = new AuthController();
Field usersDaoField = ctrl.getClass().getDeclaredField("usersDao");
usersDaoField.setAccessible(true);
usersDaoField.set(ctrl, mockUsersDao);
Field tokensDaoField = ctrl.getClass().getDeclaredField("tokensDao");
tokensDaoField.setAccessible(true);
tokensDaoField.set(ctrl, mockTokensDao);
Token t = (Token) ctrl.getToken("test", "aergaeg");
Assert.assertNotNull(t);
} catch (Exception ex) {
System.out.println(ex);
}
}
}
I don't know advantages and disadvantages for this way but this is working. This technic has a little bit more code but these codes can be seperated by different methods etc. There are more good answers for this question but I want to point to different solution. Sorry for my bad english. Have a good java to everybody :)
Look at this link
Then write your test case as
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration({"/applicationContext.xml"})
public class MyLauncherTest{
#Resource
private MyLauncher myLauncher ;
#Test
public void someTest() {
//test code
}
}

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