Don't print deferred backtraces into the logs #19061
Description
Description:
Currently, Synapse prints backtraces when a media download timeout is reached. Example:
1970-01-01 00:00:00,000 - synapse.media.media_repository - 966 - ERROR - GET-2713980 - Failed to fetch remote media <domain>/<id>
Traceback (most recent call last):
File "/usr/local/lib/python3.12/site-packages/synapse/media/media_repository.py", line 921, in _federation_download_remote_file
res = await self.client.federation_download_media(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/synapse/federation/federation_client.py", line 1959, in federation_download_media
return await self.transport_layer.federation_download_media(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/synapse/federation/transport/client.py", line 912, in federation_download_media
return await self.client.federation_get_file(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/synapse/http/matrixfederationclient.py", line 1758, in federation_get_file
multipart_response = await make_deferred_yieldable(deferred)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/twisted/internet/defer.py", line 1187, in __iter__
yield self
File "/usr/local/lib/python3.12/site-packages/twisted/internet/defer.py", line 1092, in _runCallbacks
current.result = callback( # type: ignore[misc]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/twisted/internet/defer.py", line 824, in convertCancelled
return toCall(result, timeout)
^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/twisted/internet/defer.py", line 297, in _cancelledToTimedOutError
raise TimeoutError(timeout, "Deferred")
twisted.internet.defer.TimeoutError: (60.0, 'Deferred')
The timeout is already logged and in general I think it makes sense to only show critical backtraces in the log since it clutters it a lot.