How to write a mockito test case for ResourceAssembler with in Spring Hateos? - spring-mvc

Question

I am trying to write a unit test for the below Assembler but i keep getting Could not find current request via RequestContextHolder. Is this being called from a Spring MVC handler?. I wanted to know how i can mock out the resource creation?
#Component
public class LoginResourceAssembler extends ResourceAssemblerSupport<User, ResourceSupport> {
public LoginResourceAssembler() {
super(User.class, ResourceSupport.class);
}
#Override
public ResourceSupport toResource(User user) {
ResourceSupport resource = new ResourceSupport();
final String id = user.getId();
resource.add(linkTo(MyAccountsController.class).slash(id).slash("accounts").withRel("accounts"));
return resource;
}
}

Answer 1

Instead of changing from a plain unit test to a IMO integration test (given dependency of the spring framework) you could do something like:
#RunWith(MockitoJUnitRunner.class)
public class LoginResourceAssemblerTest {
#InjectMocks
private LoginResourceAssembler loginResourceAssembler;
#Before
public void setup() {
RequestContextHolder.setRequestAttributes(new ServletRequestAttributes(new MockHttpServletRequest()));
}
#Test
public void testToResource() {
//...
}
}

Answer 2

I was seeing the error Could not find current request via RequestContextHolder. Is this being called from a Spring MVC handler because my test class was annotated with #RunWith(MockitoJUnitRunner.class) and this was not injecting the controller.
To fix this error, i annotated my test case with
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = Application.class)
#WebAppConfiguration
A working test case in my case
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = Application.class)
#WebAppConfiguration
public class LoginResourceAssemblerTest {
#Autowired
private WebApplicationContext context;
private MockMvc mockMvc;
#InjectMocks
private LoginResourceAssembler loginResourceAssembler;
#Before
public void setUp() {
initMocks(this);
this.mockMvc = MockMvcBuilders.webAppContextSetup(this.context).build();
}
#Test
public void testToResource() {
User user = new User();
user.setId("1234");
ResourceSupport resource = loginResourceAssembler.toResource(user);
assertEquals(1,resource.getLinks().size());
assertEquals("accounts",resource.getLinks().get(0).getRel());
assertTrue(resource.getLinks().get(0).getHref().contains("accounts"));
}
}