public class HelloMessageService implements MessageService {

	@PreAuthorize("authenticated")
	public String getMessage() {
		Authentication authentication = SecurityContextHolder.getContext()
															 .getAuthentication();
		return "Hello " + authentication;
	}
}

Hello org.springframework.security.authentication.UsernamePasswordAuthenticationToken@ca25360: Principal: org.springframework.security.core.userdetails.User@36ebcb: Username: user; Password: [PROTECTED]; Enabled: true; AccountNonExpired: true; credentialsNonExpired: true; AccountNonLocked: true; Granted Authorities: ROLE_USER; Credentials: [PROTECTED]; Authenticated: true; Details: null; Granted Authorities: ROLE_USER

Before we can use Spring Security Test support, we must perform some setup. An example can be seen below:

@RunWith(SpringJUnit4ClassRunner.class) 
@ContextConfiguration 
public class WithMockUserTests {

This is a basic example of how to setup Spring Security Test. The highlights are:

Remember we added the @PreAuthorize annotation to our HelloMessageService and so it requires an authenticated user to invoke it. If we ran the following test, we would expect the following test will pass:

@Test(expected = AuthenticationCredentialsNotFoundException.class)
public void getMessageUnauthenticated() {
	messageService.getMessage();
}

The question is "How could we most easily run the test as a specific user?" The answer is to use @WithMockUser. The following test will be ran as a user with the username "user", the password "password", and the roles "ROLE_USER".

@Test
@WithMockUser
public void getMessageWithMockUser() {
String message = messageService.getMessage();
...
}

Specifically the following is true:

Our example is nice because we are able to leverage a lot of defaults. What if we wanted to run the test with a different username? The following test would run with the username "customUser". Again, the user does not need to actually exist.

@Test
@WithMockUser("customUsername")
public void getMessageWithMockUserCustomUsername() {
	String message = messageService.getMessage();
...
}

We can also easily customize the roles. For example, this test will be invoked with the username "admin" and the roles "ROLE_USER" and "ROLE_ADMIN".

@Test
@WithMockUser(username="admin",roles={"USER","ADMIN"})
public void getMessageWithMockUserCustomUser() {
	String message = messageService.getMessage();
	...
}

If we do not want the value to automatically be prefixed with ROLE_ we can leverage the authorities attribute. For example, this test will be invoked with the username "admin" and the authorities "USER" and "ADMIN".

@Test
@WithMockUser(username = "admin", authorities = { "ADMIN", "USER" })
public void getMessageWithMockUserCustomAuthorities() {
	String message = messageService.getMessage();
	...
}

Of course it can be a bit tedious placing the annotation on every test method. Instead, we can place the annotation at the class level and every test will use the specified user. For example, the following would run every test with a user with the username "admin", the password "password", and the roles "ROLE_USER" and "ROLE_ADMIN".

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration
@WithMockUser(username="admin",roles={"USER","ADMIN"})
public class WithMockUserTests {

While @WithMockUser is a very convenient way to get started, it may not work in all instances. For example, it is common for applications to expect that the Authentication principal be of a specific type. This is done so that the application can refer to the principal as the custom type and reduce coupling on Spring Security.

The custom principal is often times returned by a custom UserDetailsService that returns an object that implements both UserDetails and the custom type. For situations like this, it is useful to create the test user using the custom UserDetailsService. That is exactly what @WithUserDetails does.

Assuming we have a UserDetailsService exposed as a bean, the following test will be invoked with an Authentication of type UsernamePasswordAuthenticationToken and a principal that is returned from the UserDetailsService with the username of "user".

@Test
@WithUserDetails
public void getMessageWithUserDetails() {
	String message = messageService.getMessage();
	...
}

We can also customize the username used to lookup the user from our UserDetailsService. For example, this test would be executed with a principal that is returned from the UserDetailsService with the username of "customUsername".

@Test
@WithUserDetails("customUsername")
public void getMessageWithUserDetailsCustomUsername() {
	String message = messageService.getMessage();
	...
}

Like @WithMockUser we can also place our annotation at the class level so that every test uses the same user. However unlike @WithMockUser, @WithUserDetails requires the user to exist.

We have seen that @WithMockUser is an excellent choice if we are not using a custom Authentication principal. Next we discovered that @WithUserDetails would allow us to use a custom UserDetailsService to create our Authentication principal but required the user to exist. We will now see an option that allows the most flexibility.

We can create our own annotation that uses the @WithSecurityContext to create any SecurityContext we want. For example, we might create an annotation named @WithMockCustomUser as shown below:

@WithSecurityContext(factory = WithMockCustomUserSecurityContextFactory.class)
public @interface WithMockCustomUser {

	String username() default "rob";

	String name() default "Rob Winch";
}

You can see that @WithMockCustomUser is annotated with the @WithSecurityContext annotation. This is what signals to Spring Security Test support that we intend to create a SecurityContext for the test. The @WithSecurityContext annotation requires we specify a SecurityContextFactory that will create a new SecurityContext given our @WithMockCustomUser annotation. You can find our WithMockCustomUserSecurityContextFactory implementation below:

public class WithMockCustomUserSecurityContextFactory
	implements WithSecurityContextFactory<WithMockCustomUser> {
	@Override
	public SecurityContext createSecurityContext(WithMockCustomUser customUser) {
		SecurityContext context = SecurityContextHolder.createEmptyContext();

		CustomUserDetails principal =
			new CustomUserDetails(customUser.name(), customUser.username());
		Authentication auth =
			new UsernamePasswordAuthenticationToken(principal, "password", principal.getAuthorities());
		context.setAuthentication(auth);
		return context;
	}
}

We can now annotate a test class or a test method with our new annotation and Spring Security’s WithSecurityContextTestExcecutionListener will ensure that our SecurityContext is populated appropriately.

When creating your own WithSecurityContextFactory implementations, it is nice to know that they can be annotated with standard Spring annotations. For example, the WithUserDetailsSecurityContextFactory uses the @Autowired annotation to acquire the UserDetailsService:

final class WithUserDetailsSecurityContextFactory
	implements WithSecurityContextFactory<WithUserDetails> {

	private UserDetailsService userDetailsService;

	@Autowired
	public WithUserDetailsSecurityContextFactory(UserDetailsService userDetailsService) {
		this.userDetailsService = userDetailsService;
	}

	public SecurityContext createSecurityContext(WithUserDetails withUser) {
		String username = withUser.value();
		Assert.hasLength(username, "value() must be non empty String");
		UserDetails principal = userDetailsService.loadUserByUsername(username);
		Authentication authentication = new UsernamePasswordAuthenticationToken(principal, principal.getPassword(), principal.getAuthorities());
		SecurityContext context = SecurityContextHolder.createEmptyContext();
		context.setAuthentication(authentication);
		return context;
	}
}