Building Authorization Data problem

I use this code via command line but I have the error call to a member function createRolle on null on line 14.

The command line is yii rbac/init as http://www.yiiframework.com/doc-2.0/guide-security-authorization.html#access-control-filter


namespace app\commands;


use Yii;

use yii\console\Controller;




class RbacController extends Controller

{

    public function actionInit()

    {

        $auth = Yii::$app->authManager;


        $admin = $auth->createRole('admin');

        $auth->add($admin);

        $mod= $auth->createRole('moderator');

        $auth->add($mod);




        


        // Assign roles to users. 1 and 2 are IDs returned by IdentityInterface::getId()

        // usually implemented in your User model.

      //  $auth->assign($author, 2);

       // $auth->assign($admin, 1);

    }

}

That’s because you haven’t configured your authManager.

http://www.yiiframework.com/doc-2.0/guide-concept-configurations.html