Mockito when statement not triggering during Spring Boot REST Controller Test - spring-boot

Question

I've written a typical three layer Spring Boot REST API and am building out the tests for it. The API itself works fine but I am running into issues getting the controller tests to work. The body that's being returned is empty because the object the controller layer is getting back is null. Here are the main dependencies in play.
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.12.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-test</artifactId>
<scope>test</scope>
</dependency>
I've mocked out the service layer but the when statement in the test doesn't seem to be firing as I'd expect.
Here's the test itself:
#RunWith(SpringRunner.class)
#SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.MOCK)
#AutoConfigureMockMvc
public class VehicleControllerTest {
#MockBean
VehicleServiceImpl vService;
#Mock
HttpServletRequest mockRequest;
#Mock
Principal mockPrincipal;
#Autowired
MockMvc mockMvc;
Vehicle vehicle1;
#BeforeEach
public void setUp() throws ItemNotFoundException {
vehicle1 = new Vehicle();
vehicle1.setVin("5YJ3E1EA5KF328931");
vehicle1.setColor("black");
vehicle1.setDisplayName("Black Car");
vehicle1.setId(1L);
}
#Test
#WithMockUser("USER")
public void findVehicleByIdSuccess() throws Exception {
//Given **I think the problem is here***
when(vService.findVehicleById(any(),any(),any())).thenReturn(vehicle1);
//When
this.mockMvc.perform(get("/vehicles/1")).andDo(print())
//Then
.andExpect(status().isOk());
}
}
Here's the corresponding controller method:
#Secured("ROLE_USER")
public class VehicleController {
#JsonView(VehicleView.summary.class)
#GetMapping("/vehicles/{id}")
public Vehicle findVehicleById(#PathVariable Long id, Principal principal,
HttpServletRequest request) throws ItemNotFoundException {
log.info("In controller " +LogFormat.urlLogFormat(request,principal.getName()));
return vehicleService.findVehicleById(id,principal, request);
}
Here's the MockHTTPServletResponse. It has a status of 200 but the body is empty
MockHttpServletResponse:
Status = 200
Error message = null
Headers = [X-Content-Type-Options:"nosniff", X-XSS-Protection:"1; mode=block", Cache-Control:"no-cache, no-store, max-age=0, must-revalidate", Pragma:"no-cache", Expires:"0", X-Frame-Options:"DENY"]
Content type = null
Body =
Forwarded URL = null
Redirected URL = null
Cookies = []
For reference here's the service method that I'm trying to Mock
#Override
public Vehicle findVehicleById(Long id, Principal principal, HttpServletRequest request) throws ItemNotFoundException {
Optional<Vehicle> vehicle = vehicleRepository.findByIdAndUserId(id,principal.getName());
if (vehicle.isPresent()){
return vehicle.get();
} else {
throw new ItemNotFoundException(id,"vehicle");
}
}
I've tried different versions of Springboot but that hasn't helped. I had started off using 2.2.4 but I figured I would try the 2.1.X train since it has been around longer. I can confirm the correct method in the controller is being called because of the log output I'm getting.

Answer 1

Try replacing the following line:
when(vService.findVehicleById(any(),any(),any())).thenReturn(vehicle1);
with this (explicitity provide the class in any()):
when(vService.findVehicleById(any(Long.class),any(Principal.class),any(HttpServletRequest.class))).thenReturn(vehicle1);
Ignore the following part, as #M. Deinum pointed out that #MockBean does inject the mock object so this is irrelevant.
You did mock your service object but you didn't inject it into your controller.
#InjectMocks
private VehicleController vehicleController = new VehicleController();
Initialize these mock objects using MockitoAnnotations.initMocks(this) and instead of autowiring MockMvc object try to pass your controller in it like this:
#BeforeEach
void setup() {
MockitoAnnotations.initMocks(this);
this.mockMvc = MockMvcBuilders.standaloneSetup(vehicleController).build();