Adds new config option `cleanup_extremities_with_dummy_events` which
periodically sends dummy events to rooms with more than 10 extremities.
THIS IS REALLY EXPERIMENTAL.
If we remove support for a particular room version, we should behave more
gracefully. This should make client requests fail with a 400 rather than a 500,
and will ignore individiual PDUs in a federation transaction, rather than the
whole transaction.
Currently we only have the one event format version defined, but this
adds the necessary infrastructure to persist and fetch the format
versions alongside the events.
We specify the format version rather than the room version as:
1. We don't necessarily know the room version, existing events may be
either v1 or v2.
2. We'd need to be careful to prevent/handle correctly if different
events in the same room reported to be of different versions, which
sounds annoying.
If we receive an event that doesn't pass their content hash check (e.g.
due to already being redacted) then we hit a bug which causes an
exception to be raised, which then promplty stops the event (and
request) from being processed.
This effects all sorts of federation APIs, including joining rooms with
a redacted state event.
They raised KeyError before. I'm changing this because the code uses
hasattr() to check for the presence of a key. This worked accidentally
before, because hasattr() silences all exceptions in python 2. However,
in python3, this isn't the case anymore.
I had a look around to see if anything depended on this raising a
KeyError and I couldn't find anything. Of course, I could have simply
missed it.
Signed-off-by: Adrian Tschira <nota@notafile.com>
Move the checks for whether an event is new state inside persist
event itself.
This was harder than expected because there wasn't enough information
passed to persist event to correctly handle invites from remote servers
for new rooms.
