测试 Spring @MVC 注释

Question

前几天我遇到了一个问题，@Valid 注释被意外地从控制器类中删除。不幸的是，它没有破坏我们的任何测试。我们的单元测试都没有真正运用 Spring AnnotationMethodHandlerAdapter 路径。我们只是直接测试我们的控制器类。

如果我的 @MVC 注释错误，如何编写会正确失败的单元或集成测试？有没有办法让 Spring 使用 MockHttpServlet 或其他东西找到并使用相关控制器？

Answer 1

我为这种事情编写集成测试。假设您有一个带有验证注释的 bean：

public class MyForm {
    @NotNull
    private Long myNumber;

    ...
}

和一个处理提交的控制器

@Controller
@RequestMapping("/simple-form")
public class MyController {
    private final static String FORM_VIEW = null;

    @RequestMapping(method = RequestMethod.POST)
    public String processFormSubmission(@Valid MyForm myForm,
            BindingResult result) {
        if (result.hasErrors()) {
            return FORM_VIEW;
        }
        // process the form
        return "success-view";
    }
}

，并且您想要测试 @Valid 和 @NotNull 注释是否正确连接：

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration({"file:web/WEB-INF/application-context.xml",
    "file:web/WEB-INF/dispatcher-servlet.xml"})
public class MyControllerIntegrationTest {

    @Inject
    private ApplicationContext applicationContext;

    private MockHttpServletRequest request;
    private MockHttpServletResponse response;
    private HandlerAdapter handlerAdapter;

    @Before
    public void setUp() throws Exception {
        this.request = new MockHttpServletRequest();
        this.response = new MockHttpServletResponse();

        this.handlerAdapter = applicationContext.getBean(HandlerAdapter.class);
    }

    ModelAndView handle(HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        final HandlerMapping handlerMapping = applicationContext.getBean(HandlerMapping.class);
        final HandlerExecutionChain handler = handlerMapping.getHandler(request);
        assertNotNull("No handler found for request, check you request mapping", handler);

        final Object controller = handler.getHandler();
        // if you want to override any injected attributes do it here

        final HandlerInterceptor[] interceptors =
            handlerMapping.getHandler(request).getInterceptors();
        for (HandlerInterceptor interceptor : interceptors) {
            final boolean carryOn = interceptor.preHandle(request, response, controller);
            if (!carryOn) {
                return null;
            }
        }

        final ModelAndView mav = handlerAdapter.handle(request, response, controller);
        return mav;
    }

    @Test
    public void testProcessFormSubmission() throws Exception {
        request.setMethod("POST");
        request.setRequestURI("/simple-form");
        request.setParameter("myNumber", "");

        final ModelAndView mav = handle(request, response);
        // test we're returned back to the form
        assertViewName(mav, "simple-form");
        // make assertions on the errors
        final BindingResult errors = assertAndReturnModelAttributeOfType(mav, 
                "org.springframework.validation.BindingResult.myForm", 
                BindingResult.class);
        assertEquals(1, errors.getErrorCount());
        assertEquals("", errors.getFieldValue("myNumber"));        
    }

请参阅我的博客文章 集成测试 Spring 的 MVC注释

Answer 2

当然。您的测试没有理由不能实例化自己的 DispatcherServlet，将它与容器中的各种项目（例如 ServletContext）一起注入，包括上下文定义文件。

为此，Spring 附带了各种与 servlet 相关的 MockXYZ 类，包括 MockServletContext、MockHttpServletRequest 和 MockHttpServletResponse。它们并不是通常意义上的真正的“模拟”对象，它们更像是愚蠢的存根，但它们完成了工作。

servlet 的测试上下文将包含通常的 MVC 相关 bean，以及要测试的 bean。 servlet 初始化后，创建模拟请求和响应，并将它们提供给servet 的service() 方法。如果请求正确路由，您可以检查写入模拟响应的结果。

Answer 3

在即将推出的 spring 3.2（可用快照）或使用 spring-test-mvc (https://github.com/SpringSource/spring-test-mvc) 中，您可以这样做：

首先我们模拟验证，因为我们不想测试验证器，只想知道验证是否被调用。

public class LocalValidatorFactoryBeanMock extends LocalValidatorFactoryBean
{
    private boolean fakeErrors;

    public void fakeErrors ( )
    {
        this.fakeErrors = true;
    }

    @Override
    public boolean supports ( Class<?> clazz )
    {
        return true;
    }

    @Override
    public void validate ( Object target, Errors errors, Object... validationHints )
    {
        if (fakeErrors)
        {
            errors.reject("error");
        }
    }
}

这是我们的测试类：

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration
public class RegisterControllerTest
{
 @Autowired
 private WebApplicationContext  wac;
 private MockMvc mockMvc;

     @Autowired
     @InjectMocks
     private RegisterController registerController;

     @Autowired
     private LocalValidatorFactoryBeanMock  validator;

  @Before
  public void setup ( )
  {
     this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
     // if you want to inject mocks into your controller
             MockitoAnnotations.initMocks(this);
  }

    @Test
    public void testPostValidationError ( ) throws Exception
    {
        validator.fakeErrors();
        MockHttpServletRequestBuilder post = post("/info/register");
        post.param("name", "Bob");
        ResultActions result = getMockMvc().perform(post);
            // no redirect as we have errors
        result.andExpect(view().name("info/register"));
    }

    @Configuration
    @Import(DispatcherServletConfig.class)
    static class Config extends WebMvcConfigurerAdapter
    {
        @Override
        public Validator getValidator ( )
        {
            return new LocalValidatorFactoryBeanMock();
        }

        @Bean
        RegisterController registerController ( )
        {
            return new RegisterController();
        }
    }
}