使用 Mockito 在客户端测试 POST 请求

Question

我想测试应该向“服务器”发送发布请求的发布方法（所以我想模拟来自服务器的响应并检查响应）。另外，我想测试响应在正文中是否包含 http 状态 OK。问题：我应该如何使用 mockito 来做到这一点？

我在客户端（客户端）中的发布方法：

public class Client{
        public static void sendUser(){

        String url = "http://localhost:8080/user/add";

        HttpHeaders requestHeaders = new HttpHeaders();
        requestHeaders.setContentType(MediaType.APPLICATION_JSON);
        requestHeaders.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));

        User test = new User();
        test.setName("test");
        test.setEmail("a@hotmail.com");
        test.setScore(205);

        RestTemplate restTemplate = new RestTemplate();
        HttpEntity<User> request = new HttpEntity<>(test);

        ResponseEntity<String> response = restTemplate.exchange(url, HttpMethod.POST, request, String.class);

        if(response.getStatusCode() == HttpStatus.OK){
            System.out.println("user response: OK");
        }

      }
  }

另一个模块中的我的控制器（服务器端）：

@RestController
@RequestMapping("/user")
public class UserController
{
    @Autowired
    private UserRepository userRepository;

    @PostMapping("/add")
    public ResponseEntity addUserToDb(@RequestBody User user) throws Exception
    {
        userRepository.save(user);
        return ResponseEntity.ok(HttpStatus.OK);
    }

测试：

    @RunWith(SpringRunner.class)
@ActiveProfiles("test")
@SpringBootTest(classes = Client.class)
@AutoConfigureMockMvc
public class ClientTest
{

    private MockRestServiceServer mockServer;

    @Autowired
    private RestTemplate restTemplate; 

    @Autowired
    private MockMvc mockMvc;

    @Before
    public void configureRestMVC()
    {
        mockServer =
                MockRestServiceServer.createServer(restTemplate);
    }

    @Test
    public void testRquestUserAddObject() throws Exception
    {

        User user = new User("test", "mail", 2255);

        Gson gson = new Gson();

        String json = gson.toJson(user );

        mockServer.expect(once(), requestTo("http://localhost:8080/user/add")).andRespond(withSuccess());


        this.mockMvc.perform(post("http://localhost:8080/user/add")
                .content(json)
                .contentType(MediaType.APPLICATION_JSON))
                .andDo(print()).andExpect(status().isOk())
                .andExpect(content().json(json));
    }

}

现在我收到了这个错误：

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'ClientTest': Unsatisfied dependency expressed through field 'restTemplate'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'org.springframework.web.client.RestTemplate' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

Answer 1

根据您的客户端类，建议进行以下更改以使其更好地可测试：

    //  class
    public class Client {

        /*** restTemplate unique instance for every unique HTTP server. ***/
        @Autowired
        RestTemplate restTemplate;

        public ResponseEntity<String> sendUser() {

        String url = "http://localhost:8080/user/add";

        HttpHeaders requestHeaders = new HttpHeaders();
        requestHeaders.setContentType(MediaType.APPLICATION_JSON);
        requestHeaders.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));

        User test = new User();
        test.setName("test");
        test.setEmail("a@hotmail.com");
        test.setScore(205);

        HttpEntity<User> request = new HttpEntity<>(test);

        ResponseEntity<String> response = restTemplate.exchange(url, HttpMethod.POST, request, String.class);

        if(response.getStatusCode() == HttpStatus.OK){
            System.out.println("user response: OK");
        }
        return response;
      }
  }

然后对于上面我们Junit作为：

@RunWith(MockitoJUnitRunner.class)
public class ClientTest {

  private String RESULT = "Assert result";

  @Mock
  private RestTemplate restTemplate;

  @InjectMocks
  private Client client;

  /**
   * any setting needed before load of test class
   */
  @Before
  public void setUp() {
    // not needed as of now
  }

  // testing an exception scenario
  @Test(expected = RestClientException.class)
  public void testSendUserForExceptionScenario() throws RestClientException {

    doThrow(RestClientException.class).when(restTemplate)
        .exchange(anyString(), any(HttpMethod.class), any(HttpEntity.class), any(Class.class));
    // expect RestClientException
    client.sendUser();
  }

  @Test
  public void testSendUserForValidScenario() throws RestClientException {

    // creating expected response
    User user= new User("name", "mail", 6609); 
    Gson gson = new Gson(); 
    String json = gson.toJson(user); 
    doReturn(new ResponseEntity<String>(json, HttpStatus.OK)).when(restTemplate)
        .exchange(anyString(), any(HttpMethod.class), any(HttpEntity.class), any(Class.class));
    // expect proper response
    ResponseEntity<String> response =
        (ResponseEntity<String>) client.sendUser();
    assertEquals(this.RESULT, HttpStatus.OK, response.getStatusCode());
  }
}

基本上在您的sendResponse() 函数中，我们这样做：

// we are getting URL , creating requestHeader
// finally creating HttpEntity<User> request 
// and then passing them restTemplate.exchange 
// and then restTemplate is doing its job to make a HTPP connection and getresponse...
// and then we are prinnting the response... somestuff 

因此，在相应的测试中，我们也应该只测试函数在做什么 由于restTemplate 正在处理连接，并且您没有覆盖restTemplate 的任何工作，所以我们不应该为此做任何事情...... 而只是测试我们的代码/逻辑。

最后，确保导入看起来像：

可以肯定的是，导入将是这样的：

import org.springframework.http.HttpEntity; 
import org.springframework.http.HttpHeaders; 
import org.springframework.http.HttpMethod; 
import org.springframework.http.HttpStatus; 
import org.springframework.http.MediaType; 
import org.springframework.http.ResponseEntity; 
import org.springframework.web.client.RestTemplate;

希望这会有所帮助。

Answer 2

先完整代码（解释如下）：

import static org.springframework.test.web.client.ExpectedCount.manyTimes;
import static org.springframework.test.web.client.ExpectedCount.once;
import static org.springframework.test.web.client.match.MockRestRequestMatchers.requestTo;
import static org.springframework.test.web.client.response.MockRestResponseCreators.withSuccess;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

@RunWith(SpringRunner.class)
@ActiveProfiles("test")
@SpringBootTest
@AutoConfigureMockMvc
public class MyTestClass {

MockRestServiceServer mockServer;

    @Autowired
    private RestTemplate restTemplate;  //create a bean somewhere. It will be injected here. 

    @Autowired
    private MockMvc mockMvc;

    @Before
    public void configureRestMVC(){
        mockServer =
                MockRestServiceServer.createServer(restTemplate);
    }

    @Test
    public void test0() throws Exception {
        //this is where you would mock the call to endpoint and and response
        mockServer.expect(once(), requestTo("www.example.com/endpoint1"))
        .andRespond(withSuccess());
    ... 
    //here you will actually make a call to your controller. If the service class is making a post call to another endpoint outside, that you just mocked in above statement.
    this.mockMvc.perform(post("www.example2.com/example2endpoint")
                .content(asJsonString(new YouCustomObjectThatYouWantToPost))
                .contentType(MediaType.APPLICATION_JSON))
        .andDo(print()).andExpect(status().isOk())
        .andExpect(content().json(matchResponseAgainstThisObject()));
   }

您需要使用@AutoConfigureMockMvc 注释。背后的目的是根本不启动服务器，而只测试其下的层，Spring 处理传入的 HTTP 请求并将其交给您的控制器。这样，几乎使用了整个堆栈，并且您的代码将被调用，就好像它正在处理一个真正的 HTTP 请求一样，但没有启动服务器的成本。为此，我们将使用 Spring 的 MockMvc，我们可以通过在测试类上使用 @AutoConfigureMockMvc 注释来请求为我们注入它。

private MockRestServiceServer mockServer;

MockRestServiceServer 是客户端 REST 测试的主要入口点。用于涉及直接或间接使用 RestTemplate 的测试。提供一种方法来设置将通过 RestTemplate 执行的预期请求以及发送回的模拟响应，从而消除对实际服务器的需求。

mockServer.expect(once(), requestTo("www.example.com/endpoint1"))
    .andRespond(withSuccess());

您可以在此处设置模拟外部呼叫的位置。并设置预期。

this.mockMvc.perform(post("www.example2.com/example2endpoint")..

这是您实际调用您自己的端点的地方，即您在控制器中定义的端点。 Spring 将访问您的端点，执行您在控制器/服务层中拥有的所有逻辑，当涉及到实际在外部进行调用的部分时，将使用您刚刚在上面定义的 mockServer。这样，它就完全离线了。你从来没有打过实际的外部服务。此外，您将在相同的 mockMvc.perform 方法上附加您的断言。