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POCometD / jQuery Client Error 402::Unknown Client
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  1. POCometD / jQuery Client Error 402::Unknown Client
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    copied!<p>I'm trying to get started with CometD as I need some empirical background for a technical comparision between various push technologies.</p> <p>I finally managed to get an example code running in my Tomcat (v7.0). </p> <p>Now I'm having strange behavior and I'm desperately trying to find out what I did wrong. </p> <p><strong>Here are my observations:</strong></p> <ul> <li><p>Connection Loops:</p> <p>I'm running in an endless connection loop with the client.</p> <p>Request:</p> <pre><code>[{"channel":"/meta/connect","connectionType":"long-polling","id":"19","clientId":"f1le33y91f6pa71f39z52km87yp"}] </code></pre> <p>Response:</p> <pre><code>[{"id":"19","successful":true,"advice":{"interval":2000,"reconnect":"retry","multiple-clients":true,"timeout":60000},"channel":"/meta/connect"}] </code></pre> <p>The interesting thing about this is, that the Listener-callback event actually occures</p> <pre><code> cometd.addListener('/meta/handshake', _metaHandshake); </code></pre></li> <li><p>Client connection request stucks</p> <p>This mostly occurs after a fresh restart of my Tomcat server. I can see a successful subscription to 2 channels:</p> <p>Request</p> <pre><code>[{"version":"1.0","minimumVersion":"0.9","channel":"/meta/handshake","supportedConnectionTypes":["long-polling","callback-polling"],"advice":{"timeout":60000,"interval":0},"id":"1"}] </code></pre> <p>Response</p> <pre><code>[{"id":"1","minimumVersion":"1.0","supportedConnectionTypes":["callback-polling","long-polling"],"successful":true,"channel":"/meta/handshake","clientId":"11tnpjnmkqo3tf64zcvufuqbtv","version":"1.0"}] </code></pre> <p>Request</p> <pre><code>[{"channel":"/meta/subscribe","subscription":"/hello","id":"2","clientId":"11tnpjnmkqo3tf64zcvufuqbtv"},{"channel":"/service/hello","data":{"name":"World"},"id":"3","clientId":"11tnpjnmkqo3tf64zcvufuqbtv"}] </code></pre> <p>Response</p> <pre><code>[{"id":"2","subscription":"/hello","successful":true,"channel":"/meta/subscribe"},{"id":"3","successful":true,"channel":"/service/hello"}] </code></pre> <p>The call after this one stucks and takes forever.</p></li> </ul> <p><strong>... abd here is my Code</strong></p> <ul> <li><p>Client</p> <pre><code>(function($) { var cometd = $.cometd; $(document).ready(function() { function _connectionEstablished() { $('#body').append('&lt;div&gt;CometD Connection Established&lt;/div&gt;'); } function _connectionBroken() { $('#body').append('&lt;div&gt;CometD Connection Broken&lt;/div&gt;'); } function _connectionClosed() { $('#body').append('&lt;div&gt;CometD Connection Closed&lt;/div&gt;'); } // Function that manages the connection status with the Bayeux server var _connected = false; function _metaConnect(message) { if (cometd.isDisconnected()) { _connected = false; _connectionClosed(); return; } var wasConnected = _connected; _connected = message.successful === true; if (!wasConnected &amp;&amp; _connected) { _connectionEstablished(); } else if (wasConnected &amp;&amp; !_connected) { _connectionBroken(); } } // Function invoked when first contacting the server and // when the server has lost the state of this client function _metaHandshake(handshake) { if (handshake.successful === true) { // interesting enough: that event is triggered alert('event occured'); cometd.batch(function() { // that function is called and produces a corresponding request to the server cometd.subscribe('/hello', function(message) { // that one never happens... $('#body').append('&lt;div&gt;Server Says: ' + message.data.greeting + '&lt;/div&gt;'); }); // Publish on a service channel since the message is for the server only cometd.publish('/service/hello', { name: 'World' }); }); } } // Disconnect when the page unloads $(window).unload(function() { cometd.disconnect(true); }); var cometURL = location.protocol + "//" + location.host + config.contextPath + "/cometd"; cometd.configure({ url: cometURL, logLevel: 'debug' }); cometd.addListener('/meta/handshake', _metaHandshake); cometd.addListener('/meta/connect', _metaConnect); cometd.handshake(); }); })(jQuery); </code></pre></li> <li><p>Server</p> <p>Notice that this is almost 1:1 from the example from the distribution package!</p> <pre><code>public class HelloService extends AbstractService { public HelloService(BayeuxServer bayeux) { super(bayeux, "hello"); addService("/service/hello", "processHello"); } public void processHello(ServerSession remote, Message message) { Map&lt;String, Object&gt; input = message.getDataAsMap(); String name = (String)input.get("name"); Map&lt;String, Object&gt; output = new HashMap&lt;String, Object&gt;(); output.put("greeting", "Hello, " + name); remote.deliver(getServerSession(), "/hello", output, null); } </code></pre> <p>}</p></li> <li><p>Web.xml File</p> <p> http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5"></p> <pre><code>&lt;servlet&gt; &lt;servlet-name&gt;cometd&lt;/servlet-name&gt; &lt;servlet-class&gt;org.cometd.server.CometdServlet&lt;/servlet-class&gt; &lt;async-supported&gt;true&lt;/async-supported&gt; &lt;init-param&gt; &lt;param-name&gt;timeout&lt;/param-name&gt; &lt;param-value&gt;60000&lt;/param-value&gt; &lt;/init-param&gt; &lt;init-param&gt; &lt;param-name&gt;logLevel&lt;/param-name&gt; &lt;param-value&gt;3&lt;/param-value&gt; &lt;/init-param&gt; &lt;/servlet&gt; &lt;servlet-mapping&gt; &lt;servlet-name&gt;cometd&lt;/servlet-name&gt; &lt;url-pattern&gt;/cometd/*&lt;/url-pattern&gt; &lt;/servlet-mapping&gt; </code></pre> <p></p></li> </ul> <p>Maybe I'm just doing something completely wrong, but I'm starting to get a bit desperate on this. Help would be highly appreciated.</p>
 

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