setting a mapping for mapper-attachments

PUT intranet_dev/_mapping/modelresult
{
   "properties": {
        "document_file": {
         "fields": {
            "content_length": {
               "type": "integer",
               "store": "yes"
            },
            "language": "french",
            "title": {
               "analyzer": "french", 
               "store": "yes"
            },
            "user_author": {
               "analyzer": "ngram_analyzer",
               "store": "yes"
            },
            "content": {
               "index": true,
               "term_vector": "with_positions_offsets",
               "analyzer": "french",
               "copy_to": "copy",
               "type": "string",
               "store": "yes"
            },
            "content_type": {
               "analyzer": "ngram_analyzer",
               "store": "yes"
            }
         },
         "type": "attachment"
      }
   }
}