ElasticSearch terms aggregation by entire field

Update at 2018-02-11 now we can use syntax .keyword after grouped by field according to this

GET /bank/_search
{
  "size": 0,
  "aggs": {
    "group_by_state": {
      "terms": {
        "field": "state.keyword"
      }
    }
  }
}

This elastic doc suggests to fix that in mapping (as suggested in the accepted answer) - either to make the field not_analyzed or to add a raw field with not_analyzed and use it in aggregations.

There is no other way for it. As the aggregations operate upon inverted index and if the field is analyzed, the inverted index is bound to have only tokens and not the original values of the field.

You should fix this in your mapping. Add a not_analyzed field. You can create the multi field if you also need the analyzed version.

"album": {
  "city": "string",
  "fields": {
    "raw": {
      "type": "string",
      "index": "not_analyzed"
    }
  }
}

Now create your aggregate on city.raw