Unit Test Async Deferred Result Controller gets hung forever - unit-testing

Question

The controller method I am testing
#GetMapping("/customers")
#ResponseBody
public DeferredResult<ResponseEntity<Resources<Resource<Customer>>>> getAllCustomers(
#PageableDefault(page = 0, size = 20) #SortDefault.SortDefaults({
#SortDefault(sort = "name", direction = Direction.ASC) }) Pageable pageable,
PagedResourcesAssembler<Customer> assembler, HttpServletRequest request) {
DeferredResult<ResponseEntity<Resources<Resource<Customer>>>> response = new DeferredResult<>(
Long.valueOf(1000000));
response.onTimeout(() -> response
.setErrorResult(ResponseEntity.status(HttpStatus.REQUEST_TIMEOUT).body("Request timed out.")));
response.onError((Throwable t) -> {
response.setErrorResult(ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body("An error occured."));
});
ListenableFuture<Page<Customer>> future = customerService.findAll(pageable);
future.addCallback(new ListenableFutureCallback<Page<Customer>>() {
#Override
public void onSuccess(Page<Customer> result) {
Link self = new Link(
ServletUriComponentsBuilder.fromRequestUri(request).buildAndExpand().toUri().toString(),
"self");
LOGGER.debug("Generated Self Link {} for Customer Resource Collection", self.getHref());
if (result.hasContent())
response.setResult(
ResponseEntity.ok(assembler.toResource(result, customerResourceAssembler, self)));
else
response.setErrorResult(ResponseEntity.notFound());
LOGGER.debug("Returning Response with {} customers", result.getNumber());
}
#Override
public void onFailure(Throwable ex) {
LOGGER.error("Could not retrieve customers due to error", ex);
response.setErrorResult(ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
.body("Could not save customers list due to server error."));
}
});
return response;
}
the unit test
#RunWith(SpringRunner.class)
#WebMvcTest(CustomerController.class)
#EnableSpringDataWebSupport
#Import({ CustomerResourceAssember.class, BranchResourceAssembler.class, InvoiceResourceAssembler.class,
CustomerAsyncService.class })
public class CustomerControllerTests {
#Autowired
private MockMvc mockMvc;
#Autowired
CustomerAsyncService customerService;
#MockBean
private CustomerRepository customerRepository;
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
}
#Test
public void testWhenNoCustomersThenReturnsEmptyHALDocument() throws Exception {
// Given
BDDMockito.given(customerRepository.findAll(PageRequest.of(0, 20)))
.willReturn(new PageImpl<Customer>(Collections.emptyList()));
// When
MvcResult result = mockMvc.perform(get("/customers").accept(MediaTypes.HAL_JSON_VALUE)).andDo(print())
.andExpect(request().asyncStarted())
.andExpect(request().asyncResult(new PageImpl<Customer>(Collections.emptyList()))).andReturn();
// Then
mockMvc.perform(asyncDispatch(result)).andExpect(status().isOk());
}
This test neve completes, doesn't even time out on my IDE, I have to kill it everytime I run it, if run the entire app however this /customers endpoint gives a 404 when there are no customers added to the application.
What do I need to do make sure this test completes, the CustomerService call ultimately calls CustomerRepository which I have mocked because I couldn't get my brains around how to mock the async call to service method. the customer service class is as follows
#Async
#Service
public class CustomerAsyncService {
private CustomerRepository customerRepository;
#Autowired
public CustomerAsyncService(CustomerRepository customerRepository) {
this.customerRepository = customerRepository;
}
#Transactional(readOnly = true, isolation = Isolation.SERIALIZABLE)
public ListenableFuture<Page<Customer>> findAll(Pageable pageable) {
return AsyncResult.forValue(customerRepository.findAll(pageable));
}
I was hoping mocking the Repository method would do the trick. How do I mock the async service call

Answer 1

My bad was using mocks wrongly, this worked
#RunWith(SpringRunner.class)
#WebMvcTest(CustomerController.class)
#Import({ CustomerResourceAssember.class, BranchResourceAssembler.class, InvoiceResourceAssembler.class,
CustomerAsyncService.class })
public class CustomerControllerTests {
#MockBean
private CustomerRepository customerRepository;
#InjectMocks
CustomerAsyncService customerService = new CustomerAsyncService(customerRepository);
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
JacksonTester.initFields(this, objectMapper);
}
#Test
public void testReturnsNotFoundForEmptyGetAllCustomersResult() throws Exception {
// Given
Page<Customer> emptyPage = new PageImpl<Customer>(Collections.emptyList());
BDDMockito.given(customerRepository.findAll(any(Pageable.class))).willReturn(emptyPage);
// When
MvcResult result = mockMvc.perform(get("/customers")).andExpect(request().asyncStarted()).andDo(print()).andReturn();
// Then
mockMvc.perform(asyncDispatch(result)).andDo(print()).andExpect(status().isNotFound());
}
}