Symfony authentication not intercepting login request

I'm reworking my Silex application to Symfony 4, as Silex will be deprecated in a couple of months. Everything works great, but I'm having a bit of a problem with Symfony's Security Bundle.

The problem is I'm trying to log into the application, but it always redirects me back to my application without any error displayed.

I guess it might be a misconfiguration, but I have been looking for any kind of problems for a while now and I can't seem to find any errors.

Here's my security.yaml

providers:
    in_memory:
        memory:
            users:
                admin:
                    password: foo
                    roles: ROLE_ADMIN
encoders:
    Symfony\Component\Security\Core\User\User: plaintext
firewalls:
    dev:
        pattern: ^/(_(profiler|wdt)|css|images|js)/
        security: false
    login:
        context: 'secured'
        pattern: '^/login'
        anonymous: true
        provider: in_memory
    secured_area:
        context: 'secured'
        pattern: '^(/admin|/api)'
        provider: in_memory
        form_login:
            login_path: /login/
            check_path: /admin/check/
            default_target_path: /admin/
        logout:
            path: /admin/logout/
            target: /
            invalidate_session: true

access_control:
    - { path: '^(/admin|/api)', roles: ROLE_ADMIN }

LoginController

/**
 * @Route("/login/", name="login")
 */
public function login(Request $request, AuthorizationCheckerInterface $authChecker, AuthenticationUtils $authUtils): Response
{
    $isLoggedIn = $authChecker->isGranted('ROLE_ADMIN');
    if ($isLoggedIn) {
        return $this->redirectToRoute('admin');
    }
    return $this->render('login/index.html.twig', [
        'error'         => $authUtils->getLastAuthenticationError(),
        'last_username' => $authUtils->getLastUsername()
    ]);
}

I tried setting check_path option to /login/check/ and other similar routes, but then Symfony threw an exception that the route is not created (I guess it shouldn't be created).

Solution

So, after trying to solve this issue for a half of day, I finally realized what did I do wrong. Unlike Silex, Symfony is not creating routes for login_check and logout by itself. I needed to register the routes somehow in order to run it smoothly.

You can either register the routes in routes.yaml or using annotations.