Cometd: Mutliple callbacks on handler if a user subscribe-unsubscribe-subscribe to a channel.

[guest]

If a user subscribes to a channel then unsubscribes and subscribes again, there will be 2 callbacks on the handler when a message is published.

var handler = {

receive: function(obj) {

console.debug("NEW MESSAGE: ", obj.data.message); alert("new message: " + obj.data.message);

}

}

function init() {

dojox.cometd.init(new String(document.location).replace(/​http://[^/]*/,'')+"cometd");

}

function subscribe() {

dojox.cometd.subscribe("/messages", handler, "receive");

}

function unsubscribe() {

dojox.cometd.unsubscribe("/messages", handler, "receive");

}

function disconnect() {

dojox.cometd.disconnect();

}

function publish(id) {

dojox.cometd.publish("/messages", {message: document.getElementById(id).value});

}

To reproduce:

init(); subscribe(); publish('test1'); unsubscribe(); subscribe(); publish('test2');

There will be 2 'test2' messages received by the handler. Depending on how many times the user subscribe-unsubscribe, that will be the number of messages(duplicate) that will be received.

[guest]

dojox.cometd fix patch

[guest]

Hi Alex,

I've attached the fix for this bug.

Cheers, David

dyu@…

[gregwilkins]

David,

could you improve this patch a little bit:

the topics map probably should be called _topics

the _subscriptions array should be removed and disconnect should iterate the through the values of the _topics map. Actually then _topics could best be called _subscriptions!

Remove the FIXME comment about not doing the unsubscribe properly as it is fixed!

[gregwilkins]

Also the test in subscribe and unsubscribe for

(useLocalTopics !== true)

(useLocalTopics !== false)

should be

(useLocalTopics !== true)&&(useLocalTopics !== false)

[dylan]

This appears to have been fixed with work Greg did a while back, closing as fixed.