fix: call _heroku.pg_stat_statements_reset() on Essential and Advanced plans

[dasofiei]

Summary

• heroku pg:outliers --reset was calling pg_stat_statements_reset() directly for all plans
• On Essential/Advanced, the real function is no longer granted to tenants — they have a SECURITY DEFINER wrapper _heroku.pg_stat_statements_reset() scoped to the current database only
• Now uses getAttachment to detect the plan and calls the right function per fleet:
  • Essential & Advanced : SELECT _heroku.pg_stat_statements_reset()
  • Standard and below : SELECT pg_stat_statements_reset()

Change is not in shogun yet, it will be merged on Monday evening, right before the minor release.
There will be a brief period of time where the reset cli command won't work for essential & performance plans, in-between shogun release & cli release.

It can be tested using my shogun as below.

Type of Change

• fix: Bug fix

Testing

Tests:

npx mocha --require ts-node/register test/unit/commands/pg/outliers.unit.test.ts

getting statement count:
SELECT count(*) FROM pg_stat_statements WHERE dbid = (SELECT   oid FROM pg_database WHERE datname = current_database())  AND userid = (SELECT usesysid FROM pg_user WHERE usename =  current_user);

calling reset:
HEROKU_DATA_HOST=shogun.dasofiei.herokudev.com HEROKU_DATA_SERVICE=heroku-postgresql-dasofiei ./bin/run pg:outliers --reset HEROKU_POSTGRESQL_DASOFIEI_RED_URL --app dasofiei-public

End-to-end:

1. Build: `npm run build`
2. On an Essential database: `heroku pg:outliers --reset --app ` — should succeed and return cleanly
3. Verify the reset only cleared that database's stats — connect to a second Essential on the same cluster, confirm its `pg_stat_statements` count is unchanged
4. On a Standard database: `heroku pg:outliers --reset --app ` — should succeed using the real function directly

Related

Shogun PR: https://github.com/heroku/shogun/pull/22200
Reset docs -> https://devcenter.heroku.com/articles/heroku-cli-commands#heroku-pg-outliers-database

[sbosio]

@dasofiei I did a small change removing the extra resolution step, because the add-on info is already present on the attachment key for the database resolver and this avoids another slow request to Platform API. I had to improve a little bit the mocked data on tests so they resemble better the actual information returned by that database resolver and smoke tested all commands to ensure it continues working.

In my case that I was testing against prod, for Advanced and Essential DBs I've got an error related with the wrapper function not existing in the database engine, but I guess that has to do with the backend not being updated yet. Can you test against your development add-on and let me know if everything looks ok? That way I can approve and merge and we should be ready for the release.

[dasofiei]

Tested successfully against an advanced, it reset the statements.

[sbosio]

Looks good!