Inject @AuthenticationPrincipal when unit testing a Spring REST controller

Question

I am having trouble trying to test a REST endpoint that receives an UserDetails as a parameter annotated with @AuthenticationPrincipal.

It

Answer 1

For some reason Michael Piefel's solution didn't work for me so I came up with another one.

First of all, create abstract configuration class:

@RunWith(SpringRunner.class)
@SpringBootTest
@TestExecutionListeners({
    DependencyInjectionTestExecutionListener.class,
    DirtiesContextTestExecutionListener.class,
    WithSecurityContextTestExecutionListener.class})
public abstract MockMvcTestPrototype {

    @Autowired
    protected WebApplicationContext context;

    protected MockMvc mockMvc;

    protected org.springframework.security.core.userdetails.User loggedUser;

    @Before
    public voivd setUp() {
         mockMvc = MockMvcBuilders
            .webAppContextSetup(context)
            .apply(springSecurity())
            .build();

        loggedUser =  (User)  SecurityContextHolder.getContext().getAuthentication().getPrincipal();
    } 
}

Then you can write tests like this:

public class SomeTestClass extends MockMvcTestPrototype {

    @Test
    @WithUserDetails("someUser@app.com")
    public void someTest() throws Exception {
        mockMvc.
                perform(get("/api/someService")
                    .withUser(user(loggedUser)))
                .andExpect(status().isOk());

    }
}

And @AuthenticationPrincipal should inject your own User class implementation into controller method

public class SomeController {
...
    @RequestMapping(method = POST, value = "/update")
    public String update(UdateDto dto, @AuthenticationPrincipal CurrentUser user) {
        ...
        user.getUser(); // works like a charm!
       ...
    }
}