While I was going through uses of preserve_fn for other PRs, I converted places
which only use the wrapped function once to use run_in_background, to avoid
creating the function object.
We need to be careful (under python 2, at least) that when we reraise an
exception after doing some error handling, we actually reraise the original
exception rather than anything that might have been raised (and handled) during
the error handling.
There were a bunch of places where we fire off a process to happen in the
background, but don't have any exception handling on it - instead relying on
the unhandled error being logged when the relevent deferred gets
garbage-collected.
This is unsatisfactory for a number of reasons:
- logging on garbage collection is best-effort and may happen some time after
the error, if at all
- it can be hard to figure out where the error actually happened.
- it is logged as a scary CRITICAL error which (a) I always forget to grep for
and (b) it's not really CRITICAL if a background process we don't care about
fails.
So this is an attempt to add exception handling to everything we fire off into
the background.
In most cases, we limit the number of prev_events for a given event to 10
events. This fixes a particular code path which created events with huge
numbers of prev_events.
The intention was for the check to be called as early as possible in the
request, but actually was called just before the main ratelimit check,
so was fairly pointless.
In newer versions of https://github.com/esnme/ultrajson, ujson does not
serialize frozendicts (introduced in esnme/ultrajson@53f85b1). Although
the PyPI version is still 1.35, Fedora ships with a build from commit
esnme/ultrajson@2f1d487. This causes the serialization to fail if the
distribution-provided package is used.
This runs the event through the unfreeze utility before serializing it.
Thanks to @ignatenkobrain for tracking down the root cause.
fixes#2351
Signed-off-by: Jeremy Cline <jeremy@jcline.org>
Since we didn't instansiate the PusherPool at start time it could fail
at run time, which it did for some users.
This may or may not fix things for those users, but it should happen at
start time and stop the server from starting.