模拟服务功能未按预期工作

Question

这是我的代码。我不明白为什么它不起作用。问题在于 test 中的行：

when(applicationUserRepository.findApplicationUserByUsername("testUser"))
        .thenReturn(userToReturnFromRepository);

似乎什么也没做。当函数 findApplicationUserByUsername 应该返回 userToReturnFromRepository 的可选项时，它会返回一个空的可选项。

控制器：

@RestController
@RequestMapping("api/v1/exercises")
public class ExerciseController {
    
    @Autowired
    ExerciseService exerciseService;

    @GetMapping
    public List<Exercise> getExercises() {

        List<Exercise> exercises = exerciseService.getAllExercises();
        return exercises;
    }
}

服务：

@Service("exerciseService")
public class ExerciseService {
    
    @Autowired
    ExerciseRepository exerciseRepository;

    @Autowired
    ApplicationUserRepository applicationUserRepository;
 
    @Transactional
    public List<Exercise> getAllExercises() {
        
        Principal principal = SecurityContextHolder.getContext().getAuthentication();

        Optional<ApplicationUser> applicationUser = applicationUserRepository.findApplicationUserByUsername(principal.getName());
                
        List<Exercise> exercises = new ArrayList<>();
        if(applicationUser.isPresent()){
            exercises = applicationUser.get().getExercises();
               
            }

        return exercises;
    }
}

测试：

@SpringBootTest
@AutoConfigureMockMvc(addFilters = false)
public class ExerciseControllerTest {

    private final MockMvc mockMvc;
    private final ObjectMapper objectMapper;
    @Mock
    ApplicationUserRepository applicationUserRepository;
    
    @Autowired
    public ExerciseControllerTest(MockMvc mockMvc,
            ApplicationUserRepository applicationUserRepository, ObjectMapper objectMapper) {
        this.mockMvc = mockMvc;
        this.applicationUserRepository = applicationUserRepository;
        this.objectMapper = objectMapper;
    }

    @BeforeEach
    public void initMocks() {
        MockitoAnnotations.openMocks(this);
    }

    @Test
    @WithMockUser(username = "testUser")
    public void testGetExercises() throws Exception {
        
         Exercise ex = new Exercise();
         ex.setData("test");
         ApplicationUser user = new ApplicationUser();
         Exercise[] exercises = {ex};
         List<Exercise> list = new ArrayList<Exercise>(Arrays.asList(exercises));
         user.setExercises(list);
         Optional<ApplicationUser> userToReturnFromRepository = Optional.of(user);

        when(applicationUserRepository.findApplicationUserByUsername("testUser"))
        .thenReturn(userToReturnFromRepository);

        mockMvc.perform(get("/api/v1/exercises")).andExpect(status().isOk()).andExpect(jsonPath("$", hasSize(1)));


    }
}

Answer 1

您的测试中发生了两件相互矛盾的事情：

1. 您正在使用 Mockito 通过反射来初始化模拟实现
2. 您已经通过构造函数将 ApplicationUserRepository 注入到测试类中。

最终发生的事情是这样的：

1. spring 将 applicationUserRepository 注入到构造函数参数中
2. applicationUserRepository 字段在构造函数中设置为 spring 注入版本
3. Mockito 初始化一个新的 applicationUserRepository 模拟
4. Mockito 将 applicationUserRespository 字段替换为 mock（即，再见了您的 MVC 设置正在使用的 spring bean 的句柄！）

我能想到的最简单的修复方法是使用@MockBean 而不是@Mock 结合构造函数注入。 @MockBean 将指示 Spring 为您创建模拟实例，使用它，并在测试中提供给您。

@SpringBootTest
@AutoConfigureMockMvc(addFilters = false)
public class ExerciseControllerTest {

    private final MockMvc mockMvc;
    private final ObjectMapper objectMapper;
    @MockBean // User MockBean instead of Mock
    ApplicationUserRepository applicationUserRepository;
    
    @Autowired
    public ExerciseControllerTest(MockMvc mockMvc, ObjectMapper objectMapper) {
        this.mockMvc = mockMvc;
        //remove the applicationUserRepository injection
        this.objectMapper = objectMapper;
    }

// remove MockitoAnnotations.openMocks(this);
//...

...
}