How do I mock an OAuth2Authentication Object in Spring Test - spring-security

Question

I would like to test my rest controller in spring. In my the service, a user requires to pass an authentication token. I use a token utils class that decodes the token and get an organization id. I then use the id for several processes. How do I do a mock of this in Spring? I have followed this documentation but am getting a 404 on running the test.
TodoController
#RequestMapping("todos")
class TodoController {
#Autowired
lateinit var todoService: TodoService
#Autowired
lateinit var tokenUtils: TokenUtils
#GetMapping
fun getAllTodos(authentication: OAuth2Authentication): ResponseEntity<List<Todo>> {
tokenUtils.init(authentication);
val organizationId = tokenUtils.organizationId
return ResponseEntity.ok(todoService.findAll(organizationId))
}```
I am a bit new to spring tests and will appreciate any help accorded

Answer 1

First you need to create a mock Authentication class that implements Authentication interface. Most of following code is auto generated. Override any method you you need (in this case, I only override getPrincipal method).
import java.util.Collection;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;
public class MockPrincipal implements Authentication {
public MockPrincipal() {}
#Override
public String getName() {
// TODO Auto-generated method stub
return null;
}
#Override
public Collection<? extends GrantedAuthority> getAuthorities() {
// TODO Auto-generated method stub
return null;
}
#Override
public Object getCredentials() {
// TODO Auto-generated method stub
return null;
}
#Override
public Object getDetails() {
// TODO Auto-generated method stub
return null;
}
#Override
public Object getPrincipal() {
// TODO Auto-generated method stub
return "mock user";
}
#Override
public boolean isAuthenticated() {
// TODO Auto-generated method stub
return false;
}
#Override
public void setAuthenticated(boolean isAuthenticated) throws IllegalArgumentException {
// TODO Auto-generated method stub
}
}
After that you can mock up an OAuth2Authentication object like this:
MockPrincipal mockUser = new MockPrincipal();
OAuth2Authentication mockOAuth2Object = new OAuth2Authentication(null, mockUser);