cakephp 3如何防止同一用户名/密码同时登录多个？

use Cake\Controller\Controller;
use Cake\Event\Event;

class AppController extends Controller
{
    public function initialize()
    {
        parent::initialize();
        $this->loadComponent('Flash');
        $this->loadComponent('RequestHandler');
        $this->loadComponent('Cookie');
        $this->loadComponent('Auth', [
            'authenticate' => [
                'Form' => [
                    'fields' => [
                        'username' => 'username',
                        'password' => 'password'
                    ],
                    'finder' => 'auth'
                ]
            ],
            'loginAction' => [
                'controller' => 'Users',
                'action' => 'login'
            ],
            'logoutRedirect' => [
                'controller' => 'Users',
                'action' => 'login'
            ],
            'unauthorizedRedirect' => $this->referer()
        ]);
    }

    public function beforeFilter(Event $event)
    {
        $this->Auth->allow(['display']);
    }
}

use Cake\Event\Event;

class UsersController extends AppController
{
    public function login()
    {
        if ($this->request->is('post')) {
            $user = $this->Auth->identify();
            if ($user) {
                $this->Auth->setUser($user);
                // 在这里添加自定义逻辑来防止同一用户名/密码同时登录多个
                // 例如，你可以在用户登录成功后，将用户的Session ID保存到数据库中，并在每次用户登录时检查Session ID是否已存在于数据库中
                return $this->redirect($this->Auth->redirectUrl());
            } else {
                $this->Flash->error(__('Invalid username or password, try again'));
            }
        }
    }
}