/** * Finds the Relation model based on its primary key value. * If the model is not found, a 404 HTTP exception will be thrown. * @param string $role * @param string $permission * @return Relation the loaded model * @throws NotFoundHttpException if the model cannot be found */ protected function findModel($role, $permission) { if (($model = Relation::findOne(['role' => $role, 'permission' => $permission])) !== null) { return $model; } else { throw new NotFoundHttpException('The requested page does not exist.'); } }