如何使用@PathVariable 对 Spring MVC 控制器进行单元测试？

Question

我有一个类似于这个的简单带注释的控制器：

@Controller
public class MyController {
  @RequestMapping("/{id}.html")
  public String doSomething(@PathVariable String id, Model model) {
    // do something
    return "view";
  }
}

我想用这样的单元测试来测试它：

public class MyControllerTest {
  @Test
  public void test() {
    MockHttpServletRequest request = new MockHttpServletRequest();
    request.setRequestURI("/test.html");
    new AnnotationMethodHandlerAdapter()
      .handle(request, new MockHttpServletResponse(), new MyController());
    // assert something
  }
}

问题是AnnotationMethodHandlerAdapter.handler()方法抛出异常：

java.lang.IllegalStateException: Could not find @PathVariable [id] in @RequestMapping
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter$ServletHandlerMethodInvoker.resolvePathVariable(AnnotationMethodHandlerAdapter.java:642)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolvePathVariable(HandlerMethodInvoker.java:514)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:262)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:146)

Answer 1

如果您使用的是 Spring 3.0.x。

在这里，我建议使用 spring-test 而不是 spring-test-mvc 合并 Emil 和 Scarba05 答案。如果您使用的是 Spring 3.2.x 或更高版本，请跳过此答案并参考 spring-test-mvc 示例

MyControllerWithParameter.java

@Controller
public class MyControllerWithParameter {
@RequestMapping("/testUrl/{pathVar}/some.html")
public String passOnePathVar(@PathVariable String pathVar, ModelMap model){
    model.addAttribute("SomeModelAttribute",pathVar);
    return "viewName";
}
}

MyControllerTest.java

import static org.springframework.test.web.ModelAndViewAssert.assertViewName;
import java.util.HashMap;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.mock.web.MockHttpServletResponse;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.web.ModelAndViewAssert;
import org.springframework.web.servlet.HandlerAdapter;
import org.springframework.web.servlet.HandlerMapping;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = 
    {"file:src\\main\\webapp\\WEB-INF\\spring\\services\\servlet-context.xml" 
    })
public class MyControllerTest {

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

@Before
public void setUp() throws Exception {
    request = new MockHttpServletRequest();
    response = new MockHttpServletResponse();
    this.handlerAdapter = applicationContext.getBean(AnnotationMethodHandlerAdapter.class);
}

//  Container beans
private MyControllerWithParameter myController;
private ApplicationContext applicationContext;
public ApplicationContext getApplicationContext() {
    return applicationContext;
}
@Autowired
public void setApplicationContext(ApplicationContext applicationContext) {
    this.applicationContext = applicationContext;
}
public MyControllerWithParameter getMyController() {
    return myController;
}
@Autowired
public void setMyController(MyControllerWithParameter myController) {
    this.myController = myController;
}

@Test
public void test() throws Exception {
    request.setRequestURI("/testUrl/Irrelavant_Value/some.html");
    HashMap<String, String> pathvars = new HashMap<String, String>();
    // Populate the pathVariable-value pair in a local map
    pathvars.put("pathVar", "Path_Var_Value");
    // Assign the local map to the request attribute concerned with the handler mapping 
    request.setAttribute(HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE, pathvars);

    final ModelAndView modelAndView = this.handlerAdapter.handle(request, response, myController);

    ModelAndViewAssert.assertAndReturnModelAttributeOfType(modelAndView, "SomeModelAttribute", String.class);
    ModelAndViewAssert.assertModelAttributeValue(modelAndView, "SomeModelAttribute", "Path_Var_Value");
    ModelAndViewAssert.assertViewName(modelAndView, "viewName");
}

}

Answer 2

从 Spring 3.2 开始，有一种适当的方法可以以一种优雅而简单的方式进行测试。您将能够执行以下操作：

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration("servlet-context.xml")
public class SampleTests {

  @Autowired
  private WebApplicationContext wac;

  private MockMvc mockMvc;

  @Before
  public void setup() {
    this.mockMvc = webAppContextSetup(this.wac).build();
  }

  @Test
  public void getFoo() throws Exception {
    this.mockMvc.perform(get("/foo").accept("application/json"))
        .andExpect(status().isOk())
        .andExpect(content().mimeType("application/json"))
        .andExpect(jsonPath("$.name").value("Lee"));
  }
}

欲了解更多信息，请查看http://blog.springsource.org/2012/11/12/spring-framework-3-2-rc1-spring-mvc-test-framework/

Answer 3

一个很有前途的 Spring MVC 测试框架 https://github.com/SpringSource/spring-test-mvc

Answer 4

我不确定我的原始答案是否会对@PathVariable 有所帮助。我刚刚尝试测试一个@PathVariable，但出现以下异常：

org.springframework.web.bind.annotation.support.HandlerMethodInvocationException: 调用处理程序方法失败 [public org.springframework.web.servlet.ModelAndView test.MyClass.myMethod(test.SomeType)];嵌套异常是 java.lang.IllegalStateException：在 @RequestMapping 中找不到 @PathVariable [parameterName]

原因是请求中的路径变量被拦截器解析。以下方法对我有用：

import static org.springframework.test.web.ModelAndViewAssert.*;

@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 testDoSomething() throws Exception {
        request.setRequestURI("/test.html");
        request.setMethod("GET");
        final ModelAndView mav = handle(request, response);
        assertViewName(mav, "view");
        // assert something else
    }

我在integration testing spring mvc annotations添加了一篇新博文

Answer 5

我发现您可以手动将 PathVariable 映射插入到请求对象中。这显然是不理想的，但似乎有效。在您的示例中，类似于：

@Test
public void test() {
    MockHttpServletRequest request = new MockHttpServletRequest();
    request.setRequestURI("/test.html");
    HashMap<String, String> pathvars = new HashMap<String, String>();
    pathvars.put("id", "test");
    request.setAttribute(HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE, pathvars);
    new AnnotationMethodHandlerAdapter().handle(request, new MockHttpServletResponse(), new MyController());
   // assert something
}

我肯定有兴趣找到更好的选择。

Answer 6

在基于 Spring 参考手册中的术语进行集成测试之后，我会称您为什么。不如做这样的事情：

import static org.springframework.test.web.ModelAndViewAssert.*;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration({/* include live config here
    e.g. "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;
    private MyController controller;

    @Before
    public void setUp() {
       request = new MockHttpServletRequest();
       response = new MockHttpServletResponse();
       handlerAdapter = applicationContext.getBean(HandlerAdapter.class);
       // I could get the controller from the context here
       controller = new MyController();
    }

    @Test
    public void testDoSomething() throws Exception {
       request.setRequestURI("/test.html");
       final ModelAndView mav = handlerAdapter.handle(request, response, 
           controller);
       assertViewName(mav, "view");
       // assert something
    }
}

有关更多信息，我已经写了blog entry about integration testing Spring MVC annotations。

Answer 7

异常消息指的是一个“feed”变量，它不在您的示例代码中，它可能是由您未向我们展示的某些内容引起的。

此外，您的测试正在测试 Spring 和您自己的代码。这真的是你想做的吗？

最好假设 Spring 可以工作（确实如此），然后测试您自己的类，即直接调用 MyController.doSomething()。这是注释方法的一个好处 - 您不需要使用模拟请求和响应，您只需使用域 POJO。