source: Dev/branches/rest-dojo-ui/client/dojox/socket/Reconnect.js @ 256

dojo.provide("dojox.socket.Reconnect");

dojox.socket.Reconnect = function(socket, options){
        // summary:
        //              Provides auto-reconnection to a websocket after it has been closed
        //      socket:
        //              Socket to add reconnection support to.
        // returns:
        //              An object that implements the WebSocket API
        // example:
        //              You can use the Reconnect module:
        //              | dojo.require("dojox.socket");
        //              | dojo.require("dojox.socket.Reconnect");
        //              | var socket = dojox.socket({url:"/comet"});
        //              | // add auto-reconnect support
        //              | socket = dojox.socket.Reconnect(socket);
        options = options || {};
        var reconnectTime = options.reconnectTime || 10000;
        
        var connectHandle = dojo.connect(socket, "onclose", function(event){
                clearTimeout(checkForOpen);
                if(!event.wasClean){
                        socket.disconnected(function(){
                                dojox.socket.replace(socket, newSocket = socket.reconnect());
                        });
                }
        });
        var checkForOpen, newSocket;
        if(!socket.disconnected){
                // add a default impl if it doesn't exist
                socket.disconnected = function(reconnect){
                        setTimeout(function(){
                                reconnect();
                                checkForOpen = setTimeout(function(){
                                        //reset the backoff
                                        if(newSocket.readyState < 2){
                                                reconnectTime = options.reconnectTime || 10000;
                                        }
                                }, 10000);
                        }, reconnectTime);
                        // backoff each time
                        reconnectTime *= options.backoffRate || 2;
                };
        }
        if(!socket.reconnect){
                // add a default impl if it doesn't exist
                socket.reconnect = function(){
                        return socket.args ?
                                dojox.socket.LongPoll(socket.args) :
                                dojox.socket.WebSocket({url: socket.URL || socket.url}); // different cases for different impls
                };
        }
        return socket;
};