Muc addPresenceInterceptor

damencho · May 19, 2022, 7:52pm

According to the javadoc to be able to modify a presence before sending one can use addPresenceInterceptor:

igniterealtime/Smack/blob/e39adff40fd3feae41e793994f870112f57cf131/smack-extensions/src/main/java/org/jivesoftware/smackx/muc/MultiUserChat.java#L1115

      
        
                return subjectUpdatedListeners.remove(listener);
            }
            
            
/**
             * Adds a new {@link StanzaListener} that will be invoked every time a new presence
             * is going to be sent by this MultiUserChat to the server. Stanza interceptors may
             * add new extensions to the presence that is going to be sent to the MUC service.
             *
             * @param presenceInterceptor the new stanza interceptor that will intercept presence packets.
             */
            public void addPresenceInterceptor(PresenceListener presenceInterceptor) {
                presenceInterceptors.add(presenceInterceptor);
            }
            
            
/**
             * Removes a {@link StanzaListener} that was being invoked every time a new presence
             * was being sent by this MultiUserChat to the server. Stanza interceptors may
             * add new extensions to the presence that is going to be sent to the MUC service.
             *
             * @param presenceInterceptor the stanza interceptor to remove.
             */

But I see it uses addStanzaSendingListener:

github.com

igniterealtime/Smack/blob/e39adff40fd3feae41e793994f870112f57cf131/smack-extensions/src/main/java/org/jivesoftware/smackx/muc/MultiUserChat.java#L382

      
        
                            new AndFilter(fromRoomFilter,
                                          MessageWithSubjectFilter.INSTANCE,
                                          new NotFilter(MessageTypeFilter.ERROR),
                                          // According to XEP-0045 § 8.1 "A message with a <subject/> and a <body/> or a <subject/> and a <thread/> is a
                                          // legitimate message, but it SHALL NOT be interpreted as a subject change."
                                          new NotFilter(MessageWithBodiesFilter.INSTANCE),
                                          new NotFilter(MessageWithThreadFilter.INSTANCE))
                            );
            // @formatter:on
            connection.addStanzaListener(declinesListener, new AndFilter(fromRoomFilter, DECLINE_FILTER));
            connection.addStanzaSendingListener(presenceInterceptor, new AndFilter(ToMatchesFilter.create(room),
                            StanzaTypeFilter.PRESENCE));
            messageCollector = connection.createStanzaCollector(fromRoomGroupchatFilter);
            
            
// Wait for a presence packet back from the server.
            // @formatter:off
            StanzaFilter responseFilter = new AndFilter(StanzaTypeFilter.PRESENCE,
                            new OrFilter(
                                // We use a bare JID filter for positive responses, since the MUC service/room may rewrite the nickname.
                                new AndFilter(FromMatchesFilter.createBare(getRoom()), MUCUserStatusCodeFilter.STATUS_110_PRESENCE_TO_SELF),
                                // In case there is an error reply, we match on an error presence with the same stanza id and from the full

Which is fired after the packet is sent:

github.com

igniterealtime/Smack/blob/0e0c0a4093eeda85c76aafc9497bd357ec12e26c/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java#L1370

      
        
                    }
                }
                else {
                    writer.write(elementXml.toString());
                }
            
            
    if (queue.isEmpty()) {
                    writer.flush();
                }
                if (packet != null) {
                    firePacketSendingListeners(packet);
                }
            }
            if (!instantShutdown) {
                // Flush out the rest of the queue.
                try {
                    while (!queue.isEmpty()) {
                        Element packet = queue.remove();
                        if (packet instanceof Stanza) {
                            Stanza stanza = (Stanza) packet;
                            maybeAddToUnacknowledgedStanzas(stanza);

I’m I reading it wrong or it is a bug?

Flow · May 20, 2022, 11:05am

It is a bug. MultiUserChat should use XMPPConnection.addPresenceInterceptor(). However this would require API changes, which is a reason to not do it for Smack 4.4, and only fix it in the main branch.

Flow · May 21, 2022, 11:42am

Created SMACK-925. Since the functionaliy is broken is Smack 4.4 anyways, I think breaking the API in this regard shoud not be an issue. If anything, it makes the user aware that something, that’s been used, is broken.

Flow · May 21, 2022, 11:46am