/**
 * When a new topic is added under the path /chat/chatsessions/,
 * the addUser callback is called to add a representation of the
 * chat session to the agent interface.
 */

var registerTopicListener = function (session){
    var listener = {
        onDescendantNotification: function() {},
        onTopicNotification: function(topicPath, topicSpecification, type) {
                addUser(topicPath);
        },
        onClose: function() {},
        onError: function(error) {}
    };

    session.notifications.addListener(listener).then(function(reg) {
        reg.select("*chat/chatsessions/");
    });
    return session;
}