Spring Boot验证:如何测试DTO对象

Question

我在StudentController中有一个方法，我必须测试它。我想测试StudentDTO验证：

@PostMapping("successStudentAddition")
public String addStudent(@ModelAttribute("student") @Validated StudentDTO studentDTO, Errors errors, Model model) {
if (errors.hasErrors()) {
model.addAttribute(STUDENT_MODEL, studentDTO);
return "/studentViews/addStudent";
}
Student student = new Student(studentDTO.getStudentId(), studentDTO.getStudentName(), studentDTO.getStudentSurname(),
studentDTO.getStudentAge(), studentDTO.getEntryYear(), studentDTO.getGraduateYear(), studentDTO.getFacultyName(),
groupService.getGroupIdByName(studentDTO.getGroupName()));
studentService.addStudent(student);
return "/studentViews/successStudentAddition";
}

StudentDTO.class:

public class StudentDTO {
@Id
private int studentId;
@NotNull
@Size(min=2,max=30,message = "Name should consist of 2 to 30 symbols!")
private String studentName;
@NotNull
@Size(min = 2, max = 30,message = "Surname should consist of 2 to 30 symbols!")
private String studentSurname;
@NotNull
@Min(value = 10,message = "Student age should be more than 10!")
private int studentAge;
@NotNull
@Min(value = 1900,message = "Entry year should be more than 1900!")
@Max(value=2021,message = "Entry year should be less than 2021!")
private int entryYear;
@NotNull
@Min(value = 2020,message = "Graduate year should be not less than 2020!")
private int graduateYear;
@NotNull
@Size(min = 3,message = "Faculty name should consist of minimum 3 symbols!")
private String facultyName;
@NotNull
@Size(min = 4,message = "Group name should consist of 4 symbols!")
@Size(max = 4)
private String groupName;
}

我发现了一些测试的想法：

@ExtendWith(SpringExtension.class)
@SpringBootTest
class ValidatingServiceWithGroupsTest {
@Autowired
private ValidatingServiceWithGroups service;
@Test
void whenInputIsInvalidForCreate_thenThrowsException() {
InputWithGroups input = validInput();
input.setId(42L);
assertThrows(ConstraintViolationException.class, () -> {
service.validateForCreate(input);
});
}
@Test
void whenInputIsInvalidForUpdate_thenThrowsException() {
InputWithGroups input = validInput();
input.setId(null);
assertThrows(ConstraintViolationException.class, () -> {
service.validateForUpdate(input);
});
}
}

但是。如果在上面的代码中，我们在没有任何输入参数的情况下测试服务，我应该使用这样的参数来测试控制器：Errors errors和Model model。我有麻烦。

添加测试后的所有堆栈跟踪：

java.lang.IllegalStateException: Failed to load ApplicationContext
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'studentController': Unsatisfied dependency expressed through field 'studentService'; nested exception is
org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.foxminded.springboot.service.StudentService' available: expected at least 1 bean which qualifies as autowire 
candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.annotation
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.foxminded.springboot.service.StudentService' available: expected at least 1 bean which qualifies as 
autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

Answer 1

根据您在问题中提供的内容，我理解您需要在StudentDTOdto类上测试验证。您的dto类的验证将在spring自动绑定时触发。因此，要测试这种验证，您所要做的就是使用json正确调用控制器方法，json将触发验证并检查响应。如果验证失败，它将触发MethodArgumentNotValidException。默认情况下，Spring会将此异常转换为HTTP状态400(错误请求(。

@ExtendWith(SpringExtension.class)
@WebMvcTest(controllers = StudentController.class)
class StudentControllerTest {
@Autowired
private MockMvc mvc;
@Autowired
private ObjectMapper objectMapper;
@MockBean
private StudentService service;
@Test
void whenInputIsInvalid_thenReturnsStatus400() throws Exception {
Input input = invalidInput();
String body = objectMapper.writeValueAsString(input);
mvc.perform(post("/successStudentAddition")
.content(body))
.andExpect(status().isBadRequest());
}
}

但在您的情况下，当发生错误时，您将返回一个不同的视图，因此您需要对此进行测试。因此，在您的情况下测试响应，如：

this.mockMvc.perform(post("/successStudentAddition")
.accept(MediaType.TEXT_HTML))
.andExpect(status().isOk())
.andExpect(model().attribute("yourmodel", "assertIt"))
.andDo(print());