Streaming API: subscribe callback function never called?

Question

I've implemented a simple streaming api code for subscription to the push topic using a callback function. It's realy needed because the official CotemD documentation expressly points to it:

Calling subscribe() does not mean that you have completed the subscription with the server when function returns.

If you want to be certain that the server received your subscription request (or not), you can ... pass a callback function to subscribe()

Here is my subscribe function:

subscription = jQuery.cometd.subscribe('/topic/MyPushObject', 
                                        function(message){ handleMessage(message); }, 
                                        function(subscribeReply){
    // THIS PIECE OF CODE IS NEVER CALLED
    if (subscribeReply.successful){
        console.log('subscribe success');
    }
    else{
        console.log('subscribe failed');
    }
});

I can successfully subscribe to the push topic but the callback function is never called (no console log, no break points in browser).

Am I missing something here?

Answer 1

The callback function feature has been added in CometD 2.8.0.

I am guessing that SalesForce uses an older version that does not have that functionality implemented.

The current CometD version is 3.0.4, and the updated CometD 3.0.x documentation is at this address.

The best thing is to ask SalesForce what exact CometD version they are using, and if it is old, to update it to newer versions - to provide bug fixes and more functionalities.