Spring 启动测试：使用 Jackson ObjectMapper 将模型转换为 JSON 字符串时 UserControllerTest 失败

Question

我正在 Spring Boot 中测试 @RestContoller，它有一个 @PostMapping 方法，方法 @RequestBody 使用 @Valid 注释进行验证。为了测试它，我正在使用 MockMvc 并且为了填充请求正文内容我正在使用 Jackson ObjectMapper；然而，当模型通过时，测试失败：

MockHttpServletRequest:
      HTTP Method = POST
      Request URI = /api/user/register
       Parameters = {}
          Headers = [Content-Type:"application/json"]
             Body = <no character encoding set>
    Session Attrs = {}

Handler:
             Type = com.springboottutorial.todoapp.controller.UserController
           Method = public org.springframework.http.ResponseEntity<java.lang.String> com.springboottutorial.todoapp.controller.UserController.register(com.springboottutorial.todoapp.dao.model.User)

Async:
    Async started = false
     Async result = null

Resolved Exception:
             Type = org.springframework.http.converter.HttpMessageNotReadableException

ModelAndView:
        View name = null
             View = null
            Model = null

FlashMap:
       Attributes = null

MockHttpServletResponse:
           Status = 400
    Error message = null
          Headers = []
     Content type = null
             Body = 
    Forwarded URL = null
   Redirected URL = null
          Cookies = []

java.lang.AssertionError: Status 
Expected :200
Actual   :400

用户模型：

@Entity
@Table(name = "users",
        uniqueConstraints = @UniqueConstraint(columnNames = {"EMAIL"}))
public class User {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "ID")
private long id;

@Column(name = "FIRST_NAME")
@NotNull
private String firstName;

@Column(name = "LAST_NAME")
@NotNull
private String lastName;

@Column(name = "EMAIL")
@NotNull
@Email
private String emailAddress;

@Column(name = "PASSWORD")
@NotNull
private String password;

@Column(name = "CREATED_AT")
@NotNull
@Convert(converter = LocalDateTimeConveter.class)
private LocalDateTime createdAt;

@Column(name = "UPDATED_AT")
@NotNull
@Convert(converter = LocalDateTimeConveter.class)
private LocalDateTime updatedAt;

public User(@NotNull String firstName, @NotNull String lastName,
                @NotNull @Email String emailAddress, @NotNull String password,
                @NotNull LocalDateTime createdAt, @NotNull LocalDateTime updatedAt) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.emailAddress = emailAddress;
        this.password = password;
        this.createdAt = createdAt;
        this.updatedAt = updatedAt;
    }

//setters and getters: omitted

用户控制器：

@RestController
@RequestMapping("/api/user")
public class UserController {

    @Autowired
    UserService userService;

    @PostMapping("/register")
    public ResponseEntity<String> register(@RequestBody @Valid User user){
        userService.createUser(user);
        return ResponseEntity.ok().build();
    }
}

用户控制器测试：

@RunWith(SpringRunner.class)
@SpringBootTest
@AutoConfigureMockMvc(addFilters = false)
public class UserControllerTest {

    @Autowired
    MockMvc mockMvc;

    @Test
    public void whenRequestValid_thenReturnStatusOk() throws Exception{
        User user = new User("John", "QPublic", "john.public@gmail.com",
                "123456789", LocalDateTime.now(), LocalDateTime.now());      
        mockMvc.perform(MockMvcRequestBuilders.post("/api/user/register")
                .content(new ObjectMapper().writeValueAsString(user))
                .contentType(MediaType.APPLICATION_JSON)
                )
                .andExpect(MockMvcResultMatchers.status().isOk());
    }
}

当我手动构建 JSON 字符串时，测试通过：

String json = "{\n" +
                "\t\"firstName\" : \"John\",\n" +
                "\t\"lastName\" : \"QPublic\",\n" +
                "\t\"password\" : \"123456789\",\n" +
                "\t\"createdAt\" : \"2016-11-09T11:44:44.797\",\n" +
                "\t\"updatedAt\" : \"2016-11-09T11:44:44.797\",\n" +
                "\t\"emailAddress\" : \"john.public@gmail.com\"\n" +
                "}";

        mockMvc.perform(MockMvcRequestBuilders.post("/api/user/register")
                .content(json)
                .contentType(MediaType.APPLICATION_JSON)
                )
                .andExpect(MockMvcResultMatchers.status().isOk());

Answer 1

这就是我实现其余控制器测试的方式。或许能帮到你。

我有这个摘要 class 来封装关于 JSON 映射的常见测试功能。

    import lombok.SneakyThrows;
    import lombok.val;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.http.MediaType;
    import org.springframework.http.converter.HttpMessageConverter;
    import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
    import org.springframework.mock.http.MockHttpOutputMessage;

    import java.nio.charset.StandardCharsets;
    import java.util.Arrays;

    import static org.junit.Assert.assertNotNull;

    public abstract class RestControllerTest {

        private final MediaType contentType = new MediaType(MediaType.APPLICATION_JSON.getType(),
                MediaType.APPLICATION_JSON.getSubtype(),
                StandardCharsets.UTF_8);

        private HttpMessageConverter messageConverter;

        protected MediaType getContentType() {
            return contentType;
        }

        @Autowired
        void setConverters(HttpMessageConverter<?>[] converters) {
            messageConverter = Arrays.stream(converters)
                    .filter(hmc -> hmc instanceof MappingJackson2HttpMessageConverter)
                    .findAny()
                    .orElse(null);

            assertNotNull("the JSON message converter must not be null",
                    messageConverter);
        }

        @SneakyThrows
        protected String toJson(Object data) {
            val mockHttpOutputMessage = new MockHttpOutputMessage();
            messageConverter.write(
                    data, MediaType.APPLICATION_JSON, mockHttpOutputMessage);
            return mockHttpOutputMessage.getBodyAsString();
        }
    }

您可以像这样在测试中使用它class

    @WebMvcTest(UserController.class)
    @AutoConfigureMockMvc(addFilters = false)
    public class UserControllerTest extends RestControllerTest {

        @Autowired
        MockMvc mockMvc;

        @Test
        public void whenRequestValid_thenReturnStatusOk() throws Exception{
            User user = new User("John", "QPublic", "john.public@gmail.com",
                    "123456789", LocalDateTime.now(), LocalDateTime.now());      
            mockMvc.perform(MockMvcRequestBuilders.post("/api/user/register")
                    .content(toJson(user))
                    .contentType(MediaType.APPLICATION_JSON)
                    )
                    .andExpect(MockMvcResultMatchers.status().isOk());
        }
    }

希望对你有用

Answer 2

正如 chrylis 在评论中提到的，问题的发生是由于 Java 8 日期和时间 API 和 Jackson 序列化冲突。默认情况下，ObjectMapper 不理解 LocalDateTime 数据类型，所以我需要向我的 maven 添加 com.fasterxml.jackson.datatype:jackson-datatype-jsr310 依赖项，这是一个数据类型模块，让 Jackson 识别 Java 8日期和时间 API 数据类型。 and a blog post 帮助我找出了我的问题所在。

Answer 3

如果LocalDateTime不是问题，我认为我们应该在用户class中实现equals。

Answer 4

Spring 不一定为您提供 "vanilla" ObjectMapper 实例。通过让 Spring 将 ObjectMapper 实例注入测试而不是使用默认构造函数创建 ObjectMapper，您将获得一个与您的实际运行时间环境相匹配的实例，前提是您的 spring您的单元测试配置文件设置正确。

@RunWith(SpringRunner.class)
@SpringBootTest
@AutoConfigureMockMvc(addFilters = false)
public class UserControllerTest {

    @Autowired
    MockMvc mockMvc;

    @Autowired
    ObjectMapper objectMapper;

    @Test
    public void whenRequestValid_thenReturnStatusOk() throws Exception{
        User user = new User("John", "QPublic", "john.public@gmail.com",
                "123456789", LocalDateTime.now(), LocalDateTime.now());      
        mockMvc.perform(MockMvcRequestBuilders.post("/api/user/register")
                .content(objectMapper.writeValueAsString(user))
                .contentType(MediaType.APPLICATION_JSON)
                )
                .andExpect(MockMvcResultMatchers.status().isOk());
    }
}

Spring 启动测试：使用 Jackson ObjectMapper 将模型转换为 JSON 字符串时 UserControllerTest 失败

Spring Boot Test: UserControllerTest Fails When Using Jackson ObjectMapper To Convert Model To JSON String

java

validation

mockmvc

objectmapper

spring-boot-test