MultiUserChat.join with leaveSync()

[kvad]

Hello again,
after this discussion:

MultiUserChat.leave makes MultiUserChat.join async

The problem: when connection is resumed we want to join MUC again. We call MultiUserChat.join which inside calls leave(). leave() does not wait for result, it’s essentially an async call. Immediately after leave enter(…) is called and it waits for next result. However it gets result of leave and continues. Does not wait for proper MUC join result and this triggers errors if MUC message is sent immediately after join. The code for join: public synchronized void join(MucEnterConfiguration mucEnt…

we’ve got the fix with leaveSync() in join(). However this now presents another problem. If connection is interrupted (I simulate it by shutting and starting local XMPP server) then joined is still true in this if:

public synchronized void join(MucEnterConfiguration mucEnterConfiguration)
...
if (joined) {
            try {
                leaveSync();
            }

and leaveSync() sends unavailable stanza and waits for response until timeout (30 sec in my case). If you have many MUCs you could wait a very long time before you join all of them.

Not sure how to fix it

Thanks
Kvad

[Flow]

The solution of this probably involves XEP-0410: MUC Self-Ping (Schrödinger’s Chat) to update the ‘joined’ boolean prior joining a MUC again.

Please not that this is potentially also caused by the MUC service implementation not kicking participants if the MUC service shuts down.

[kvad]

Thank you Flow. I’ve crated a workaround where I loop through my chats and call leave() on each of them that has isJoined == true. Then later joining goes without delay. Works for now.