Empty respond body for post with rest assured

Question

I am using restassured with junit4. In my test method i create a object in mongodb and when i run the test it successfully persist also. But i need to store the id created so i try to get the respond body. But the response.getBody().asString() is empty.

@Test
public void testA() throws JSONException {

    Map<String,Object> createVideoAssignmentParm = new HashMap<String,Object>();
    createVideoAssignmentParm.put("test1", "123");

    Response response = expect().statusCode(201).when().given().contentType("application/json;charset=UTF-8")
            .headers(createVideoAssignmentParm).body(assignment).post("videoAssignments");
    JSONObject jsonObject = new JSONObject(response.getBody().asString());
    id= (String)jsonObject.getString("assignmentId");
}

When i invoke the rest end point externally, it returns the response body also with relevant fields so no problem with the rest API.

If no answer for above question then how would you guys test a post with return body using rest assured so that i can try that way.

My controller method looks like,

 @RequestMapping(value = "/videoAssignment", produces = APPLICATION_JSON_VALUE, consumes = APPLICATION_JSON_VALUE, method = RequestMethod.POST)
 @ResponseBody
 public HttpEntity<VideoAssignment> createVideoAssingnment(
  //@ApiParam are there..){

    //other methods
    return new ResponseEntity<>(va, HttpStatus.CREATED);
 }

Solution 1

We use a different wat to call services with RestAssured. However, if you get an empty string you can debug whether your service was called or not by using .peek().

You can use this test:

@Test
public void testStatus() 
{
    String response = 
            given()
               .contentType("application/json")
               .body(assignment)
            .when()
               .post("videoAssignments")
               .peek() // Use peek() to print the ouput
            .then()
                .statusCode(201) // check http status code
                .body("assignmentId", equalTo("584")) // whatever id you want
            .extract()
                .asString();

    assertNotNull(response);
}

Solution 2

This is where REST-Assured shines, its fluent interface is very helpful for locating the right method to use. If you're using Spring Boot, test should work without adding dependencies or configuration (except rest-assured, of course :)

Example controller

@RestController
@RequestMapping("/api")
public class Endpoints {

    public static class Assignment {
        public int id = 1;
        public String name = "Example assignment";
    }

    @RequestMapping(value = "/example",
            method = RequestMethod.POST,
            produces = MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity<Assignment> example(@RequestBody Assignment assignment) {
        return ResponseEntity.created(URI.create("/example/1"))
                .body(assignment);
    }
}

and test:

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = Application.class)
@WebAppConfiguration
@IntegrationTest("server.port:0")
public class EndpointsTest {

    @Autowired
    private ObjectMapper objectMapper;

    @Value("${local.server.port}")
    private int port;

    @Before
    public void setUp() {
        RestAssured.port = port;
    }

    @Test
    public void exampleTest() throws Exception {

        Endpoints.Assignment assignment =
            given()
            .contentType(ContentType.JSON)
            .body(objectMapper.writeValueAsBytes(new Endpoints.Assignment()))
        .when()
            .post("/api/example")
            .then().statusCode(HttpStatus.SC_CREATED)
            .extract().response()
            .as(Endpoints.Assignment.class);

        // We can now save the assignment.id
        assertEquals(1, assignment.id);
    }
}

Comments

[Harshana]

Thanks. I try using this. If i run with second body line it says, "no content-type was defined in the response". So then i add content type again as .then().statusCode(201).contentType("application/json") .body("assignmentId", equalTo("testid123")) but it says, application/json" doesn't match actual content-type. Any clue what the reason? In my controller the rest api produces and consumes attributes also defined as json. I have update my question to show how the controller api looks too.

[Harshana]

Also still when i inspect till peek(), i can see the content is null and contentType=""

[Federico Piazza]

@Harshana I suspect your controller is not well configured. It might be generating xml instead of json if wrong headers are set, you maybe need to set up Accept header as json too. Besides that, I noticed use constant name without class you may use explicitly produces=MediaType.APPLICATION_JSON_VALUE. Additionally, before using RestAssured to connect to your service, ensure you can reach your controller with another client like Postman, and once you confirm it's working then move to RestAssured