In terms aggs format cannot be used with "value_type": "string"

[imotov]

Specifying format in terms aggregation with "value_type": "string" causes unhelpful unsupported_operation_exception. I didn't verify, but based on the source of the exception the issue most likely exist in all other value sources.

To reproduce:

DELETE test?ignore_unavailable

POST test/_bulk?refresh
{"index": {}}
{"foo": 3}


POST test/_search?error_trace
{
  "size": 0,
  "aggs": {
    "test": {
      "terms": {
        "value_type": "string",
        "field": "foo",
        "format": "$#.00",
        "size": 10
      }
    }
  }
}

[elasticmachine]

Pinging @elastic/es-analytics-geo (Team:Analytics)

[imotov]

We need to make sure our format is consistent first, so I will address this after #47469.

[wchaparro]

Hey @imotov should we change the exception message as a first step, and then next step would require #47469 ?
WDYT?

[imotov]

WDYT?

I still think it would be much cleaner to address after #47469.