def delete_file
      file = Fae::File.find_by_id(params[:id])
      file.remove_asset = true
      file.save
      render body: nil
    end
def delete_file
      file = Fae::File.find_by_id(params[:id])
      file.remove_asset = true
      file.save
      render body: nil
    end
ajax delete action

 post 'files/:id/delete_file' => 'files#delete_file', as: :delete_file
 here we just remove the asset from the attached file model, because if we deleted
 the model itself, re-uploading a new one would break.