gristlabs_grist-core/app/server
Alex Hall 3dfe4be5f3 (core) Remove DB transaction from webhook update, add mutex to all webhook endpoints
Summary:
This removes problematic code that was holding a HomeDB transaction while applying user actions which could hang indefinitely, especially if the webhook queue is full as in https://grist.slack.com/archives/C05DBJ6LA1F/p1698159750945949.

The discussion about adding this code is here: https://phab.getgrist.com/D3821#inline-45054

The initial motivation was to roll back HomeDB changes if something went wrong while applying user actions, to avoid saving only part of the changes the user requested. I think it's actually fine to just allow such a partial save to happen - I don't see anything particularly undesirable about keeping an update to the webhook URL if other updates requested by the user didn't also get applied, as the fields don't affect each other.

The comment approving the transaction approach said "so we shouldn't end up leave the transaction hanging around too long" which has been falsified.

It looks like there was also some desire to prevent a mess caused by multiple simultaneous calls to this endpoint, which the transaction may have helped with a little, but didn't really seem like a solution. Comments in `Triggers.ts` also mention fears of race conditions when clearing (some of) the queue and the need for some locking. So I wrapped all webhook-related endpoints in a simple `Mutex` held by the `ActiveDoc` to prevent simultaneous changes. I *think* this is a good thing. These endpoints shouldn't be called frequently enough to create a performance issue, and this shouldn't affect actually sending webhook events when records are added/updated. And it does seem like interleaving calls to these endpoints could cause very weird problems.

Test Plan: Nothing yet, I'd like to hear if others think this is sensible.

Reviewers: paulfitz

Reviewed By: paulfitz

Differential Revision: https://phab.getgrist.com/D4111
2023-11-14 16:51:21 +02:00
..
declarations (core) disentangle some server tests, release to core, add GRIST_PROXY_AUTH_HEADER test 2022-03-24 15:11:32 -04:00
lib (core) Remove DB transaction from webhook update, add mutex to all webhook endpoints 2023-11-14 16:51:21 +02:00
utils (core) sanitizing redis errors 2023-06-06 10:51:17 +02:00
companion.ts (core) Add Support Grist page and nudge 2023-07-04 17:36:59 -04:00
declarations.d.ts (core) Faster builds all around. 2022-07-04 10:42:40 -04:00
devServerMain.ts (core) support for bundling custom widgets with the Grist app 2023-10-27 17:00:10 -04:00
generateCheckpoint.ts (core) get all tests working under python3/gvisor 2021-10-18 17:44:15 -04:00
generateInitialDocSql.ts (core) Add optional telemetry to grist-core 2023-06-07 12:00:51 -04:00
localization.ts only offer languages that have been marked as substantially complete (#466) 2023-03-28 10:59:17 -04:00
mergedServerMain.ts (core) change handling of server access prior to full configuration 2023-10-31 17:42:48 -04:00
tsconfig.json (core) Simple localization support and currency selector. 2021-08-26 13:36:49 -07:00