Ajax AddListener(...)

[lsgmasa]

testindex.htmltestindex.js

Hello

I am using activeMQ 5.2.0, and to send data between c++ code and web browser (firefox and ie).

It works good when I am sending the data from web browser to c++ code, but when I send data from c++ to web browser, the message listener doesn't get called once in a while, and the message seems lost.

Once the web browser becomes not to able to receive the messages, then it doesn't receive any message for a while, but after that it starts receiving messages again.

to make sure if ActiveMQ server is forwarding the message from c++ code to the web browser, I launched 2 web browsers on different computers. The both of them were listening to the same topic. At the beginning, if I send data from the c++ code, the both of web browsers receive the data. However, after while, once one of them stops receiving data, although the other keeping receiving it. Therefore, I believe the data is forwarded to the both web browsers, but one the one computer, somewhere at the amq.js level or lower, the messages seems ignored or lost.

I allocated 3 programmers here to debug this problem, but so far no luck. If anyone provides us with any info, idea, or whatever, I really appreciate it.

Thanks

[lsgmasa]

Finally I found a solution.
It seems the problem was _amq.js.
BTW, this problem happens even with the demo web page (chat.html)
when you reload the page a few times, you stop seeing the messages in the text box when you send a new message.

anyway, the problem is in the poll functions in _amq.js.

new Ajax.Request(amq.uri, { method: 'get', parameters: 'timeout=0', onSuccess: amq._pollHandler });

the script tries to send the 'get' to the web server, but since the 'get' commands are exactly same every time it sends, the web browsers don't send the command to the web server, and it uses cached data. There is a post in this forum long time ago telling this problem. However the post says it happens only with IE6, so I ignored the post.  After spending so many hours, I found this happens with the new IE 8 and FireFox 3.5.4.

Work-arround is to include different data in the 'get' request as the other post in this forum says:

var timeout = 40;
var now = new Date();
var data = 'timeout=' + timeout * 1000
           + '&d=' + now.getTime()
           + '&r=' + Math.random();

new Ajax.Request(amq.uri, { method: 'get', data: data, parameters: 'timeout=0', onSuccess: amq._pollHandler });

I am surprised that this has not been fixed since the post is old, and I thought there are so many people are using this technology...


amq.zip 

I attached my version _amq.js along with other js files, so that other people who have the same problem can download and use it.

you should extract the zip in the webapp root directory where your html calls the following functions:
<script type="text/javascript" src="amq/amq.js"></script>
<script type="text/javascript">amq.uri='amq';</script>

e.g. for activemq demo web site, put them like:

your activemq install dir/webapss/demo/amq/
                                                             amq.js
                                                             _amq.js
                                                             behaviour.js
                                                             prototype.js