Nextras\Orm\Model\IModel::getMetadataStorage PHP Method

    public function getMetadataStorage();

 public function onModelAttach(IModel $model)
 {
     if ($this->model && $this->model !== $model) {
         throw new InvalidStateException('Repository is already attached.');
     }
     $this->model = $model;
     $this->metadataStorage = $model->getMetadataStorage();
 }