Error Unit Testing of Spring MVC Controllers calling REST API - spring

Question

I am unit testing the spring MVC controller in my small app, but getting the following error:
INFO: **Initializing Spring FrameworkServlet ''**
Oct 30, 2015 5:37:38 PM org.springframework.test.web.servlet.TestDispatcherServlet initServletBean
INFO: FrameworkServlet '': initialization started
Oct 30, 2015 5:37:38 PM org.springframework.test.web.servlet.TestDispatcherServlet initServletBean
INFO: FrameworkServlet '': initialization completed in 2 ms
Running com.sky.testmvc.product.controller.ProductSelectionControllerTest
Tests run: 1, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 0.031 sec <<< FAILURE!
testRoot(com.sky.testmvc.product.controller.ProductSelectionControllerTest) Time elapsed: 0.031 sec <<< FAILURE!
*java.lang.AssertionError: **Status expected:<200> but was:<204>***
at org.springframework.test.util.AssertionErrors.fail(AssertionErrors.java:60)
at org.springframework.test.util.AssertionErrors.assertEquals(AssertionErrors.java:89)
at org.springframework.test.web.servlet.result.StatusResultMatchers$5.match(StatusResultMatchers.java:549)
at org.springframework.test.web.servlet.MockMvc$1.andExpect(MockMvc.java:141)
The rest controller is below:
#RestController
public class ItemRestController {
#Autowired
ItemService catalogueService;
#Autowired
LocationService locationService;
#RequestMapping(value = "/product/{customerId}", produces = {MediaType.APPLICATION_JSON_VALUE}, method = RequestMethod.GET)
public ResponseEntity<List<Item>> listCustomerProducts(#PathVariable("customerId") int customerId) {
Integer customerLocation=(Integer) locationService.findLocationByCustomerId(customerId);
List<Product> products = catalogueService.findCustomerProducts(customerLocation);
if(products.isEmpty()){
return new ResponseEntity<List<Product>>(HttpStatus.NO_CONTENT);
}
return new ResponseEntity<List<Product>>(products, HttpStatus.OK);
}
}
#RunWith(SpringJUnit4ClassRunner.class)
#WebAppConfiguration
#ContextConfiguration(classes = {TestContext.class, AppConfiguration.class}) //load your mvc config classes here
public class ItemControllerTest {
private MockMvc mockMvc;
#Autowired
private ItemService productServiceMock;
#Autowired
private WebApplicationContext webApplicationContext;
#Before
public void setUp() {
Mockito.reset(productServiceMock);
mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
}
#Test
public void testRoot() throws Exception
{
Product prod1= new Product(1L,"Orange", new ProductCategory(1,"Sports"),new CustomerLocation(2,"London"));
Product prod2= new Product(2L,"Banana", new ProductCategory(1,"Sports"),new CustomerLocation(2,"London"));
when(productServiceMock.findCustomerProducts(1L)).thenReturn(Arrays.asList(prod1, prod2));
mockMvc.perform(get("/product/{id}", 1L))
.andExpect(status().isOk())
.andExpect(content().contentType(TestUtil.APPLICATION_JSON_UTF8))
.andExpect(jsonPath("$", hasSize(2)))
.andExpect(jsonPath("$[0].productId", is(1)))
.andExpect(jsonPath("$[0].productName", is("Orange")))
.andExpect(jsonPath("$[1].productId", is(2)))
.andExpect(jsonPath("$[1].productName", is("Banana")));
verify(productServiceMock, times(1)).findCustomerProducts(1L);
verifyNoMoreInteractions(productServiceMock);
}
}
See the TestContext below:
#Configuration
public class TestContext {
private static final String MESSAGE_SOURCE_BASE_NAME = "i18n/messages";
#Bean
public MessageSource messageSource() {
ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
messageSource.setBasename(MESSAGE_SOURCE_BASE_NAME);
messageSource.setUseCodeAsDefaultMessage(true);
return messageSource;
}
#Bean
public ItemService catalogueService() {
return Mockito.mock(ItemService .class);
}
}
#Configuration
#EnableWebMvc
#ComponentScan(basePackages = "com.uk.springmvc")
public class AppConfiguration extends WebMvcConfigurerAdapter{
private static final String VIEW_RESOLVER_PREFIX = "/WEB-INF/views/";
private static final String VIEW_RESOLVER_SUFFIX = ".jsp";
#Override
public void configureViewResolvers(ViewResolverRegistry registry) {
InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
viewResolver.setViewClass(JstlView.class);
viewResolver.setPrefix(VIEW_RESOLVER_PREFIX);
viewResolver.setSuffix(VIEW_RESOLVER_SUFFIX);
registry.viewResolver(viewResolver);
}
#Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
registry.addResourceHandler("/static/**").addResourceLocations("/static/");
}
#Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
configurer.enable();
}
#Bean
public SimpleMappingExceptionResolver exceptionResolver() {
SimpleMappingExceptionResolver exceptionResolver = new SimpleMappingExceptionResolver();
Properties exceptionMappings = new Properties();
exceptionMappings.put("java.lang.Exception", "error/error");
exceptionMappings.put("java.lang.RuntimeException", "error/error");
exceptionResolver.setExceptionMappings(exceptionMappings);
Properties statusCodes = new Properties();
statusCodes.put("error/404", "404");
statusCodes.put("error/error", "500");
exceptionResolver.setStatusCodes(statusCodes);
return exceptionResolver;
}
}
As stated earlier, the application works and I can read the json returned via the browser and its displayed in my angularjs view, but the unit test is not working. Error is java.lang.AssertionError: Status expected:<200> but was:<204>.
204 - response is empty ...
Could be > Initializing Spring FrameworkServlet '' i.e. framework servlet is not initialized? Not sure.
Any help will be appreciated
My Rest Coontroller
#RestController
public class ItemRestController {
#Autowired
ItemService catalogueService; //Service which will do product retrieval
#Autowired
LocationService locationService; //Service which will retrieve customer location id using customer id
//-------------------Retrieve All Customer Products--------------------------------------------------------
#RequestMapping(value = "/product/{customerId}", produces = {MediaType.APPLICATION_JSON_VALUE}, method = RequestMethod.GET)
public ResponseEntity<List<Product>> listCustomerProducts(#PathVariable("customerId") int customerId) {
Integer customerLocation=(Integer) locationService.findLocationByCustomerId(customerId);
List<Product> products = catalogueService.findCustomerProducts(customerLocation);
if(products.isEmpty()){
return new ResponseEntity<List<Product>>(HttpStatus.NO_CONTENT);
}
return new ResponseEntity<List<Product>>(products, HttpStatus.OK);
}
}

Answer 1

As we can see from the stack trace, the test fails because of the assertion error: it expects HTTP Status 200, but gets 204, which is HTTPStatus.NO_CONTENT, which you return in controller when the list is empty.
if(products.isEmpty()){
return new ResponseEntity<List<Product>>(HttpStatus.NO_CONTENT);
}
If you want your controller to return 200 you need your CatalogueService mock to return something...

Answer 2

In your test, you are mocking ItemService (using productServiceMock), but your controller is calling instance of CatalogueService
Also make sure your mocks are properly injected, debugger is really your best friend here. I guess from your syntax, that you are using Mockito. In such case, mocked object have "$$EnhancedByMockito" in their getClass().getName() method