"On job failure" hook

[nickmarx12345678]

Hi, thanks for all your work on this. I was wondering if you have any recommendations for how to properly hook into job failures to execute cleanup or similar. For example, if I have jobs that progress through a state machine, I might want to set some record to "FAILED" if the job fails all of it's retries (send to a DLQ, increment some counters so we could alert, etc).

I see there the ability to set a customer error handler for a client. Is the thought one would have a distinct client and error handler per queue that they might need to differentiate (or a catch all error handler that differentiates by queue etc). Is there a way to distinguish between job failures that will be retried and those that have hit their limit?

The other option I was considering was some sort of polling of failed jobs but I wasn't sure if there was a better way, or if there is a better pattern for this in general

[nickmarx12345678]

I'm sorry right after I submit this I realize I only searched "retry" and "failure", and completely forgot to check for the word "hooks", which is exactly what I was asking about.

If anyone stumbles on this: https://pkg.go.dev/github.com/riverqueue/river/rivertype#HookWorkEnd

[brandur]

Yep, HookWorkEnd should do the trick.

See also general docs on hooks: https://riverqueue.com/docs/hooks

[nickmarx12345678]

I guess one follow up, is it possible to distinguish between a retryable HookWorkEnd execution vs terminal, and is there a proper way to get access to the Job args as part of the hook? The HookWorkEnd signature only passes the "maybe-error".

Hoping to understand what a typical pattern for attempting job cleanup on jobs that exhaust retries.

Possible I'm just thinking about it wrong, but I would have thought you would need references to the job arguments to target it's intended resources on failure

[brandur]

Ah yeah, actually WorkEnd should be receiving a job row and I think the fact that it's not suggests that very few people have actually found use for this particular hook as of yet. Opened #970 to add a new parameter.