MockMvc result returns null for GET request in Spring Boot-CodePudding

I have a problem with testing my Spring Boot Controller. I'm trying to test one of Controller put methods, but all I'm getting is Status expected:<200> but was:<400> error message.

My Controller:

@PutMapping(value = "/update", produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity<String> updateFields(@RequestBody List<UpdateModel> model) throws JsonProcessingException {
    return new ResponseEntity<>(vaultService.updateFields(model), HttpStatus.OK);
}

My ControllerTest: The URL is ok, and I have a list just like in the get method in my controller.

@Test
void updateFieldsTest() throws Exception {
    List<UpdateModel> response = new ArrayList<>();
    UpdateModel updateModel = new UpdateModel();
    response.add(updateModel);
    when(vaultService.updateFields(anyList()))
            .thenReturn(String.valueOf(response));

mockMvc.perform(
        MockMvcRequestBuilders.put("/api/update")
        .contentType(MediaType.APPLICATION_JSON_VALUE)
        .accept("application/json"))
        .andExpect(MockMvcResultMatchers.status().isOk());
}

And here's an error message:

MockHttpServletRequest:
      HTTP Method = PUT
      Request URI = /api/update
       Parameters = {}
          Headers = [Content-Type:"application/json;charset=UTF-8", Accept:"application/json"]
             Body = null
    Session Attrs = {}

Handler:
             Type = hr.ogcs.ltt.api.lttapi.controller.LttController
           Method = hr.ogcs.ltt.api.lttapi.controller.LttController#updateFields(List)

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 = [Vary:"Origin", "Access-Control-Request-Method", "Access-Control-Request-Headers"]
     Content type = null
             Body = 
    Forwarded URL = null
   Redirected URL = null
          Cookies = []

Status expected:<200> but was:<400>
Expected :200
Actual   :400
<Click to see difference>
java.lang.AssertionError: Status expected:<200> but was:<400>
    at org.springframework.test.util.AssertionErrors.fail(AssertionErrors.java:59)
    at org.springframework.test.util.AssertionErrors.assertEquals(AssertionErrors.java:122)
    at org.springframework.test.web.servlet.result.StatusResultMatchers.lambda$matcher$9(StatusResultMatchers.java:627)
    at org.springframework.test.web.servlet.MockMvc$1.andExpect(MockMvc.java:212)
   at hr.ogcs.ltt.api.apicontroller.ControllerTest.updateFieldsTest(ControllerTest.java:113) <31 internal lines>
   at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)<9 internal lines>
   at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)<48 internal lines>

I guess it has to be something with sending the required parameter, but I'm not sure what exactly causes this 400 error.

CodePudding user response：

You do not have content in the request

mockMvc.perform(
        MockMvcRequestBuilders.put("/api/update")
        .contentType(MediaType.APPLICATION_JSON_VALUE)
        .content(jsonString)
        .accept("application/json"))
        .andExpect(MockMvcResultMatchers.status().isOk());
}

CodePudding user response：

For anyone interested, I've managed to find a solution, so here it is.

@Test
@DisplayName("Test updateFieldsTest")
void updateFieldsTest() throws Exception {
    List<UpdateModel> response = new ArrayList<>();
    UpdateModel updateModel = new UpdateModel();
    response.add(updateModel);
    when(vaultService.updateFields(anyList()))
            .thenReturn(String.valueOf(response));

ObjectMapper objectMapper = new ObjectMapper();
String json = objectMapper.writeValueAsString(response);

mockMvc.perform(
        MockMvcRequestBuilders.put("/api/update")
        .contentType(MediaType.APPLICATION_JSON_VALUE)
        .content(json)
        .accept("application/json"))
        .andExpect(MockMvcResultMatchers.status().isOk());
}

If you compare this code with the one in my original post, the difference is in adding the ObjectMapper.