Re: [Proposal] Adding callback support for custom statistics kinds

Michael Paquier <michael@paquier.xyz>

From: Michael Paquier <michael@paquier.xyz>

To: Sami Imseih <samimseih@gmail.com>

Cc: Peter Eisentraut <peter@eisentraut.org>, Chao Li <li.evan.chao@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>

Date: 2025-12-17T22:42:00Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Fix const correctness in pgstat data serialization callbacks
- 167cb26718e3 19 (unreleased) landed
test_custom_stats: Add tests with read/write of auxiliary data
- 481783e69f14 19 (unreleased) landed
Allow cumulative statistics to read/write auxiliary data from/to disk
- 4ba012a8ed9c 19 (unreleased) landed
test_custom_stats: Test module for custom cumulative statistics
- 31280d96a648 19 (unreleased) landed
injection_points: Remove portions related to custom pgstats
- d52c24b0f808 19 (unreleased) landed
Rename routines for write/read of pgstats file
- ed823da12891 19 (unreleased) landed

On Wed, Dec 17, 2025 at 11:01:01AM -0600, Sami Imseih wrote:
> I got the attached patch ready with some additional comments in
> the callback definitions to clarify the API contract. We only need
> to call out the "header' nuance since it's a const in one callback
> and not the other. "key" is self documenting being a const in both
> cases.

The comment sounds like a good idea, so included it and applied the
result.  Thanks for looking!
--
Michael