Running aggregations on case insensitive keywords elasticsearch 5.1 -

i trying run aggregations on keywords in index want lowercase keywords while indexing , searching elastic 5.1 not support normalizer. also, don't want index them text , enable fielddata. other options accomplish this?

you use analyzer made of keyword tokenizer , lowercase token filter.

put my_index {   "settings": {     "analysis": {       "analyzer": {         "my_keyword": {            "type":      "custom",           "tokenizer": "keyword",           "filter": ["lowercase"]         }       }     }   },   "mappings": {     "my_type": {       "properties": {         "my_field": {           "type":     "text",           "analyzer": "standard",            "fields": {             "keyword": {               "type":     "text",               "analyzer": "my_keyword"              }           }         }       }     }   } }