private function _update_similar($old_hash, $new_hash, $settings)
 {
     // find all similar blocks
     $blocks_collection = $this->block_mapper->find(array('hash' => $old_hash));
     $blocks = array();
     foreach ($blocks_collection as $entity) {
         $entity->set_hash($new_hash);
         $entity->set_settings($settings);
         $this->block_mapper->save($entity);
         $blocks[$entity->get_bid()] = $this->render_block($entity);
     }
     return $blocks;
 }
 /**
  * Delete all instances of a block across styles/routes
  */
 public function delete_blocks_by_name($block_name)
 {
     $collection = $this->block_mapper->find(array('name' => $block_name));
     foreach ($collection as $entity) {
         $this->block_mapper->delete($entity);
     }
 }