[Federation] Send typing events

[APwhitehat]

• Consume typing events from typing server.
• Send the events to all joined hosts in a room

P.S. dummy api is used to emulate the type of api.OutputTypingEvent.Event as gomatrixserverlib.Event, will be removed when #569 is fixed.
Signed-off-by: Anant Prakash <anantprakashjsr@gmail.com>

[erikjohnston]

Otherwise, LGTM

[erikjohnston]

We should probably move this TODO out of dummy package now that the plan is no longer to change to using Event

[erikjohnston]

Can you expand the OutputTypingEvent doc comment to explain why we're sending both a TypingEvent and list of currently typing users?

[APwhitehat]

Nuances with the current implementation (forgot to mention earlier):

• federation EDU doesn't have the destination field. link to travis's PR.
  It feels rather unused, since the (federation) transaction would have the destination.
• processing edus does not increment the destinationQueue.sendCounter. I am not sure if this is correct.

@erikjohnston: Hope you see this before accepting this PR.

[erikjohnston]

federation EDU doesn't have the destination field. link to travis's PR.
It feels rather unused, since the (federation) transaction would have the destination.

I've just got travis to remove the destination and origin fields from his PR ftr

[APwhitehat]

I've just got travis to remove the destination and origin fields from his PR ftr

removing the origin field as well.

[APwhitehat]

processing edus does not increment the destinationQueue.sendCounter. I am not sure if this is correct.

Took a look at the origin of this, I believe this is used for logging only.
Since EDUs are short lived and can be a lot, we could ignore them in sendCounter.
Pretty easy to add if required.
/cc @erikjohnston