FluxBB\Auth\AuthenticatorInterface::login PHP Method

    public function login(array $credentials, $remember = false);

 public function run()
 {
     $credentials = ['username' => $this->get('username'), 'password' => $this->get('password')];
     $remember = $this->get('remember');
     if (!$this->auth->login($credentials, $remember)) {
         throw new Exception('Login failure.');
     }
 }