Matrix: use per-room nicknames

[nightmared]

Fixes element-hq/element-web#1336

[codeclimate]

Code Climate has analyzed commit 23e785d and detected 0 issues on this pull request.

View more on Code Climate.

[42wim]

Not sure how this works? There's only one global displayname?
https://matrix.org/docs/spec/client_server/r0.6.1#get-matrix-client-r0-profile-userid-displayname

Seems like the per-room displayname is still being worked on - element-hq/element-meta#499 / matrix-org/matrix-spec-proposals#3189

[nightmared]

In element you can already update your per-room nick with the commande /myroomnick (which as far as I understand it only send the nickname change in the affected room, the other rooms keep the current nickname).

[42wim]

Sure, but the API call here is fetching the global nick mc.GetDisplayName, there is no way to fetch the nick per room using the matrix API ?
Or am I missing something?

[nightmared]

Hmm yeah I'm not really sure, I guess this is fixed by getting the state when syncing:

GET /_matrix/client/r0/sync

Note: This endpoint supports lazy-loading. See Filtering for more information. Lazy-loading members is only supported on a StateFilter for this endpoint. When lazy-loading is enabled, servers MUST include the syncing user's own membership event when they join a room, or when the full state of rooms is requested, to aid discovering the user's avatar & displayname.

I will have to check that it also works when display names are changed while matterbridge is stopped.

[nightmared]

So, from what I understand, a server send the update when a user changes its displayname (as per https://matrix.org/docs/spec/client_server/r0.6.1#events-on-change-of-profile-information), and the server also sends that information when the bridge starts, sending all the events since that last MarkRead() (I guess that's the point where it starst sending events again). And we use that information in handleMemberChange to update the displayname for the given room (in which case we do not use the dedicated matrix APi call).

[42wim]

For the current code (and your PR) this means that there's a 10 minute delay before the nickname also changes in the other rooms because we remove the cache every 10 minutes. And we'll ask for the nickname again (using the matrix API call)

matterbridge/bridge/matrix/helpers.go

Lines 106 to 108 in 23e785d

	if now.Sub(NicknameCacheIter.lastUpdated) > 10*time.Minute {
	toDelete[channelIDIter] = mxidIter
	}

So I don't think this fixes the issue ?

[nightmared]

Oh yeah, I haven't tried this patch over sessions running long enough to hit that case. You're right, I will have to rethink this code. I'm not sure yet this is simple to do in matterbridge because there is no data persistence across restarts.

[nightmared]

I'm not currently working on this, so I'm gonna close this for now.