# Append Sub File Indexes to the Document Identifier

You can configure CFS to automatically append sub-file indexes to document identifiers, before the documents are indexed into IDOL Server.

To do this, use the lua script `identifiers.lua`, which is included with CFS in the `scripts` folder. The script is also included below:

    function handler( document )
       identifier = document:getFieldValue( "AUTN_IDENTIFIER" )

       if identifier then
          indices = document:getFieldValue( "SubFileIndexCSV" )

          if indices then
             indices = string.gsub(indices, ",", ".")
             document:setFieldValue("AUTN_IDENTIFIER", identifier .. "|" .. indices)
          end
       end

       return true
    end

You must run the script after KeyView has extracted sub-files, so run the script using a Post Import task. For example:

    [ImportTasks]
    Post0=Lua:scripts/identifiers.lua

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