How to create a general MockMvc class for multiple test classes?

Question

I am writing end to end tests for many different Spring Controllers. Right now, I am trying to write a general class for testing that contains MockMvc performing methods. I have endpoints that I need to call in different Controllers and I do not want to copy paste code around, and have a MockMvc and ObjectMapper in each test class.

Few examples of the methods:

public void saveMockDish(DishDto dishDto) throws Exception {
    mockMvc.perform(
        MockMvcRequestBuilders.post(DISH_ENDPOINT)
          .contentType(MediaType.APPLICATION_JSON)
          .content(objectMapper.writeValueAsString(dishDto)))
      .andExpect(status().isCreated());
  }


public DishDto getMockDish(Long id) throws Exception {
    MvcResult mvcResult = mockMvc.perform(MockMvcRequestBuilders
        .get(DISH_ENDPOINT + "/{id}", id))
      .andExpect(status().isOk())
      .andReturn();
    String contentAsString = mvcResult.getResponse().getContentAsString();
    return objectMapper.readValue(contentAsString, new TypeReference<>() {
    });
  }

What I am trying to accomplish (a bean that I could autowire in another class, example in DishControllerTest class):

@AutoConfigureMockMvc
@TestComponent
public class AppMockMcv {
  private static final String DISH_ENDPOINT = "/dishes";
  private static final String BASE_INGREDIENTS_ENDPOINT = "/base-ingredients";

  @Autowired
  private MockMvc mockMvc;
  @Autowired
  private ObjectMapper objectMapper;

  public List<DishDto> getMockDishes() throws Exception {
  ...

How I want to instantiate my test classes:

@SpringBootTest
public class DishControllerTest {

  @Autowired
  private AppMockMcv appMockMcv;

  @Test
  void testGetDishes() throws Exception {
    List<DishDto> dishes = appMockMcv.getMockDishes();
    assertEquals(4, dishes.size());
    assertNotNull(dishes);
    DishAssertions.containsDish(dishes, "Pasta Carbonara");
  }

Right now I am facing the issue that I can not use @AutoConfigureMockMvc together with @TestComponent, the bean is not found in autowiring. I also tried @Component, @TestConfiguration, @SpringBootTest annotations in the AppMockMcv class.

Current error, although not very useful:

No qualifying bean of type 'mtv.restaurant.mock.AppMockMcv' available: 
expected at least 1bean which qualifies as autowire candidate. 
Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)

I did not find much information on how to create a bean for testing only, also on how to combine it with AutoConfigureMockMvc. Also, I tried to find a way on how to extend MockMvc without success.

What is the right way to achieve what I am trying to accomplish?

• Spring boot 2.5.4

Answer 1

I did not find much information on how to create a bean for testing only, also on how to combine it with AutoConfigureMockMvc. Also, I tried to find a way on how to extend MockMvc without success.

If you create bean under /test/java, then it will only be used in tests(in most cases), even if the component annotation is used. Check the information here - https://docs.spring.io/spring-boot/docs/1.4.3.RELEASE/reference/html/boot-features-testing.html (40.3.2).

Also, I wrote little code for example, it works (Because you didn't provide configuration for Spring, I used only @SpringBootApplication):

package src:

@SpringBootApplication
public class Main {
    public static void main(String[] args) {
        SpringApplication.run(Main.class, args);
    }
}

package src.test:

@Component
public class CustomMockMVc {
    public MockMvc getMockMvc() {
        return mockMvc;
    }

    private final MockMvc mockMvc;

    public CustomMockMVc(MockMvc mockMvc) {
        this.mockMvc = mockMvc;
    }
}

@SpringBootTest
@AutoConfigureMockMvc
public class TestComponent {
    @Autowired
    private CustomMockMVc customMockMVc;

    @Test
    public void testMockMvc() {
        System.out.println(customMockMVc.getMockMvc());
    }
}

Answer 2

Heh, after I started learning Spring Boot I tend to forget basic Java...

The solution I came up is that I @Autowire and @AutoConfigureMockMvc in the xControllerTest class and create an instance of AppMockMcv @BeforeAll tests, where I pass in MockMvc and ObjectMapper.

That way I can invoke my requests and only have the Mvc performing methods in one class.

I will share my solution, but I would be very grateful if someone shared a beter solution, as this is not how it should be done properly.

AppMockMcv:

public class AppMockMcv {
  private static final String DISH_ENDPOINT = "/dishes";
  private static final String BASE_INGREDIENTS_ENDPOINT = "/base-ingredients";

  private final MockMvc mockMvc;
  private final ObjectMapper objectMapper;

  public AppMockMcv(MockMvc mockMvc, ObjectMapper objectMapper) {
    this.mockMvc = mockMvc;
    this.objectMapper = objectMapper;
  }

  public List<DishDto> getMockDishes() throws Exception {
    MvcResult mvcResult = mockMvc.perform(MockMvcRequestBuilders
        .get(DISH_ENDPOINT)
        .queryParam("custom", "false"))
      .andExpect(status().isOk())
      .andReturn();
    String contentAsString = mvcResult.getResponse().getContentAsString();
    return objectMapper.readValue(contentAsString, new TypeReference<>() {
    });
  }
 }

DishControllerTest:

@AutoConfigureMockMvc
@SpringBootTest
@TestInstance(TestInstance.Lifecycle.PER_CLASS)
public class DishControllerTest {

  @Autowired
  private MockMvc mockMvc;
  @Autowired
  private ObjectMapper objectMapper;

  private AppMockMcv appMockMcv;

  @BeforeAll
  public void setup() {
    appMockMcv = new AppMockMcv(mockMvc, objectMapper);
  }

  @Test
  void testGetDishes() throws Exception {
    List<DishDto> dishes = appMockMcv.getMockDishes();
    assertEquals(4, dishes.size());
    assertNotNull(dishes);
    DishAssertions.containsDish(dishes, "Pasta Carbonara");
  }
 }