MockRestServiceServer & java.lang.IllegalArgumentException: No InputStream specified

Question

I am trying to test my REST service on the client side (side calling a Spring MVC on the server).

I can hit the url with Json on the Server side using PostMan and all is good, so I know the Server side is correct.

Server Side MVC Method: ​ Code:

@RequestMapping(value = "/device/event/{type}", method = RequestMethod.POST)
@ResponseStatus(value = HttpStatus.OK)
public void processEvent(@PathVariable String type,
                @RequestBody DeviceEvent event) throws Exception {
    log.info("Device Event["+type+"] generated by Device["+event.getDeviceAddress()+"] ");

    if (StringUtils.isBlank(type) || event == null || 
        StringUtils.isBlank(event.getDeviceAddress()) || 
        StringUtils.isBlank(event.getDeviceType())) {
        return;
    }

    deviceEventHandlers.get(type).handleEvent(event);      
}

Client Side Method: Code:

public void newNodeEvent(DeviceEvent event) {
    final String apiUrl = eventRepository + "/" + DeviceEventType.DEVICE_NEW.getCode();
    this.sendEvent(event, apiUrl);
}

@Async
private void sendEvent(final DeviceEvent event, final String apiUrl) {
    try {
        ResponseEntity<String> response = restTemplate.postForEntity(new URI(apiUrl), event,
                        String.class);
        HttpStatus status = response.getStatusCode();
        if (status.value() != HttpStatus.OK.value()) {
            log.error("Event Controller returned with status code[" + status.value()
                            + "] for [" + apiUrl + "]");
        }
    }
    catch (ResourceAccessException | URISyntaxException ex) {
        log.error("Cannot connect to Event Controller, for [" + apiUrl + "]");
    }
}

Test Class: Code:

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = { AnnotationConfigContextLoader.class, MockRestConfig.class })
public class DeviceEventServiceTest {

    @Autowired
    private RestTemplate restTemplate;

    @Autowired
    private IDeviceEventService deviceEventService;

    @Value("${event.repository.path}")
    private String eventRepository;

    private MockRestServiceServer mockServer;

    @Before
    public void setUp() throws Exception {
        mockServer = MockRestServiceServer.createServer(restTemplate);
    }

    @Test
    public void testNewNodeEventTriggered() throws JsonGenerationException, 
            JsonMappingException, IOException, URISyntaxException {
        DeviceEvent de = new DeviceEvent();
        de.setHubId(123);
        de.setDeviceAddress("1234567890abcdef");
        de.setSwVersion("1.0-1");
        de.setHwVersion("1.0-1");
        de.setDeviceType(DeviceType.WIRELESS_VALVE.getCode());

        String expectedContent = JsonConverter.objectToJsonString(de, true);

        mockServer.expect(requestTo(new URI(eventRepository + "/DNW")))
            .andExpect(method(HttpMethod.POST))
            .andExpect(content().contentType(JsonConverter.APPLICATION_JSON_UTF8))
            .andExpect(content().string(expectedContent))
            .andRespond(withSuccess());

        deviceEventService.newNodeEvent(de);
        mockServer.verify();
        assertTrue(true);
    }

}

The client side code works 100% but the test fails with: java.lang.IllegalArgumentException: No InputStream specified

Any help would be very much grateful as I have spend way to much time already on this

Answer 1

Please try this:

mockServer.expect(requestTo(new URI(eventRepository + "/DNW"))).andExpect(method(HttpMethod.POST)) 
   .andExpect(content().contentType(JsonConverter.APPLICATION_JSON_UTF8))                
   .andExpect(content().string(expectedContent))
   .andRespond(withStatus(HttpStatus.OK).body(new byte[0]));

What was changed compared to yours:

... .andRespond(withSuccess()); // Yours
... .andRespond(withStatus(HttpStatus.OK).body(new byte[0])); // Suggested fix