在可分页控制器上使用WebTestClient

Question

I'm using the reactive web test alternative that comes with Spring Boot 2, and i'm trying to build a test for a controller like this:

@RestController
@RequestMapping("/users")
public class UserController{

    @Autowired
    private UserService service;

    @GetMapping
    public Page<UserDTO> get(Pageable pageable){
        return service.get(pageable);
    }
}

The test looks like this:

@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class UsersTest{

    @Autowired
    private WebTestClient webClient;

    @Test
    public void test(){
         List<UserDTO> userList = webClient.get()
            .uri("/users")
            .exchange()
            .expectStatus().isOk()
            .expectBodyList(UserDTO.class).hasSize(1)
            .returnResult()
            .getResponseBody();

        assertNotNull(userList.get(1).getId());
    }
}

The result in the request is in fact a list of 1 element, but is not properly, because the structure of the response is:

{
  "content": [
    {
      "id": 1,
      "name": "John",
      "lastName": "Doe",
      "active": true
    }
  ],
  "pageable": {
    "sort": {
      "sorted": false,
      "unsorted": true
    },
    "offset": 0,
    "pageSize": 25,
    "pageNumber": 0,
    "unpaged": false,
    "paged": true
  },
  "totalPages": 1,
  "totalElements": 1,
  "last": true,
  "size": 25,
  "number": 0,
  "numberOfElements": 1,
  "first": true,
  "sort": {
    "sorted": false,
    "unsorted": true
  }
}

So when i get the id value of that first element I obtain a null value. And the test fails.

Is there a way (maybe a Exchange Filter Function) than makes the WebTestClient understand pageable responses?

Thanks in advance for any help.

Answer 1

I think WebTestClient can understand pageable responses. The structure of the response is json, and WebTestClient provides a way to interact with json.

So if you want to test if the response contains 1 user that has an id. You can do:

  webClient.get()
           .uri("/users")
           .exchange()
           .expectBody()
           .jsonPath("$.numberOfElements").isEqualTo(1)
           .jsonPath("$.content[0].id").isNotEmpty();

Answer 2

I consider that Dirk Deyne solution is better than mine, but maybe for someone it could be useful.

I built these 3 classes using lombok :

@Data
@NoArgsConstructor
public class CustomResponsePage<T> {
    List<T> content;
    CustomPageable pageable;
    Integer totalPages;
    Integer totalElements;
    Boolean last;
    Integer size;
    Integer number;
    Long numberOfElements;
    Boolean first;
    CustomSort sort;
}

@Data
@NoArgsConstructor
public class CustomPageable{
    CustomSort sort;
    Long offset;
    Integer pageSize;
    Integer pageNumber;
    Boolean unpaged;
    Boolean paged;
}

@Data
@NoArgsConstructor
public class CustomSort {
    Boolean sorted;
    Boolean unsorted;
}

An then, I modified the test like this:

@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class UsersTest{

    @Autowired
    private WebTestClient webClient;

    @Test
    public void test(){
         PagedUserDTO pagedUserList = webClient.get()
            .uri("/users")
            .exchange()
            .expectStatus().isOk()
            .expectBody(UserDTO.class)
            .returnResult(PagedUserDTO.class)
            .getResponseBody();

        assertTrue(pagedUserList.getContent().size() == 0);
    }

    private static class PagedUserDTO extends CustomResponsePage<UserDTO> { }
}

Notice the PagedUserDTO class created at the end of the test.

It's a still in progress structure because it doesn't consider when there are order columns in the response, but in my case I don't need them.