/**
  * Get the fully qualified parent key name.
  *
  * @return string
  */
 public function getQualifiedParentKeyName()
 {
     return $this->parent->getKeyName();
 }
 /**
  * @return Descriptor
  */
 public function descriptor()
 {
     return $this->model->newDescriptor();
 }
 /**
  * @param $id
  * @return PromiseInterface
  */
 public function findAsync($id)
 {
     return $this->where($this->model->getKeyName(), $id)->firstAsync();
 }