Add args and kwargs to job context for on_job_start/on_job_end hooks

[frankie567]

on_job_start/on_job_end hooks are really useful for adding logs, setting up monitoring tasks, etc.

Currently, those hooks are passed a job context like this:

arq/arq/worker.py

Lines 551 to 560 in 9109c2e

	job_ctx = {
	'job_id': job_id,
	'job_try': job_try,
	'enqueue_time': ms_to_datetime(enqueue_time_ms),
	'score': score,
	}
	ctx = {**self.ctx, **job_ctx}
	if self.on_job_start:
	await self.on_job_start(ctx)

It would be really interesting to also have the args and kwargs so we could log them or perhaps triggering specific behavior when detecting certain arguments.

This could look like this:

job_ctx = {
    'job_id': job_id,
    'job_try': job_try,
    'enqueue_time': ms_to_datetime(enqueue_time_ms),
    'score': score,
    'args': args,
    'kwargs': kwargs,
}

If that makes sense, I would happily open a PR with the required changes.

[KShah707]

As a manual workaround for now you can of course use

job = Job(ctx["job_id"], ctx["redis"])
job_def: JobDef = await job.info()

print(job_def["args"])
print(job_def["kwargs"])