Exceptions while parsing EDUs mask the problem area of the source

[turt2live]

Description

Received this error on dev.t2bot.io:

2018-05-27 20:20:21,991 - synapse.federation.transport.server - 148 - INFO - PUT-4244- Request from zemos.net
2018-05-27 20:20:21,991 - synapse.federation.transport.server - 266 - INFO - PUT-4244- Received txn DxKPPsdBfaB6LZyKgAJ6TvpMpj8Lzfp6Qs8RkmHSpp6ot from zemos.net. (PDUs: 0, EDUs: 1, failures: 0)
2018-05-27 20:20:21,996 - synapse.federation.federation_server - 643 - ERROR - PUT-4244- Failed to handle edu 'm.typing'
Traceback (most recent call last):
  File "/home/travis/.synapse/local/lib/python2.7/site-packages/synapse/federation/federation_server.py", line 639, in on_edu
    yield handler(origin, content)
KeyError: 'room_id'

Turns out the error originated from

synapse/synapse/handlers/typing.py

Line 237 in 3c09921

room_id = content["room_id"]

Would be nice to see that in the stack trace at the least, to avoid having to reverse engineer the code.

Version information

• Homeserver: dev.t2bot.io
• Version: 0.30.0
• Install method: pip
• Platform: Ubuntu 16.04 VM on ESXi 6.5