gistfile1.txt

  def update
    @document = Document.find(params[:document_id])
    @version = @document.document_versions.find(params[:id])
    authorize_action_for(@version, parent_project)
    if @version.update_attributes(version_params)
      if !params[:version][:file].blank?
        # store document and project id in file so we can get to them later for permissions checking when file is served
        @version.reload
        @version.file.add_meta('attachable_type' => @document.class.to_s)
        @version.file.add_meta('attachable_uid' => @document.id.to_s)
        @version.file.add_meta('project_uid' => params[:project_id])
        @version.save
      end