Implement stats parameter for count queries

[anti-social]

Search API has stats parameter:

(Optional, string) Specific tag of the request for logging and statistical purposes.

It would be nice to have the same parameter for Count API.

At the moment a bad request error is returned:

{
  "error": {
    "root_cause": [
      {
        "type": "illegal_argument_exception",
        "reason": "request [/test_index/_count] contains unrecognized parameter: [stats]"
      }
    ],
    "type": "illegal_argument_exception",
    "reason": "request [/test_index/_count] contains unrecognized parameter: [stats]"
  },
  "status": 400
}

As I understand statistics for count queries goes to common search statistics. Think it will be logical to be able to tag count queries.

[elasticmachine]

Pinging @elastic/es-search (Team:Search)

[oraliahdz]

Hi, I would like to help. Is this still available?

[javanna]

@oraliahdz yes please go ahead.

[youjelly]

Hi, is anyone working on this, if not, I'd like to take it up, thanks

[oraliahdz]

I'm working on this, without much progress I'm afraid...

[andrewvanvo]

Hey @oraliahdz , have you made any progress so far? Out of curiosity I took a look through the codebase just to get familiar with it (took me a few days) and ended up making working solution on my end confirmed with curl calls to a few of the APIs.