/**
* 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.');
}
}
