longPollTransportJsonEncoded.js #1

/*
	Copyright (c) 2004-2011, The Dojo Foundation All Rights Reserved.
	Available via Academic Free License >= 2.1 OR the modified BSD license.
	see: http://dojotoolkit.org/license for details
*/


if(!dojo._hasResource["dojox.cometd.longPollTransportJsonEncoded"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojox.cometd.longPollTransportJsonEncoded"] = true;
dojo.provide("dojox.cometd.longPollTransportJsonEncoded");
dojo.require("dojox.cometd._base");

dojox.cometd.longPollTransportJsonEncoded = new function(){
	// This is an alternative implementation to that provided in logPollTransportFormEncoded.js
	// that sends messages as text/json rather than form encoding them.
	
	this._connectionType="long-polling";
	this._cometd=null;

	this.check = function(types, version, xdomain){
		return ((!xdomain)&&(dojo.indexOf(types, "long-polling") >= 0));
	}

	this.tunnelInit = function(){
		var message = {
			channel:	"/meta/connect",
			clientId:	this._cometd.clientId,
			connectionType: this._connectionType,
			id:	""+this._cometd.messageId++
		};
		message=this._cometd._extendOut(message);
		this.openTunnelWith([message]);
	}

	this.tunnelCollapse = function(){
		// TODO handle transport specific advice
		
		if(!this._cometd._initialized){ return; }
			
		if(this._cometd._advice && this._cometd._advice["reconnect"]=="none"){
			return;
		}
		if (this._cometd._status=="connected") {
			setTimeout(dojo.hitch(this,function(){this._connect();}),this._cometd._interval());
		}else{
			setTimeout(dojo.hitch(this._cometd,function(){this.init(this.url,this._props);}),this._cometd._interval());
		}
	}

	this._connect = function(){
		if(!this._cometd._initialized){ return; }
		if(this._cometd._polling) {
			return;
		}
			
		if((this._cometd._advice) && (this._cometd._advice["reconnect"]=="handshake")){
			this._cometd._status="unconnected";
			this._initialized = false;
			this._cometd.init(this._cometd.url,this._cometd._props);
 		}else if(this._cometd._status=="connected"){
			var message={
				channel:	"/meta/connect",
				connectionType: this._connectionType,
				clientId:	this._cometd.clientId,
				id:	""+this._cometd.messageId++
			};
			if (this._cometd.connectTimeout>=this._cometd.expectedNetworkDelay){
				message.advice={timeout:(this._cometd.connectTimeout-this._cometd.expectedNetworkDelay)};
			}
			message=this._cometd._extendOut(message);
			this.openTunnelWith([message]);
		}
	}

	this.deliver = function(message){
		// Nothing to do
	}

	this.openTunnelWith = function(messages, url){
		this._cometd._polling = true;
		var post = {
			url: (url||this._cometd.url),
			postData: dojo.toJson(messages),
			contentType: "text/json;charset=UTF-8",
			handleAs: this._cometd.handleAs,
			load: dojo.hitch(this, function(data){
				this._cometd._polling=false;
				this._cometd.deliver(data);
				this._cometd._backon();
				this.tunnelCollapse();
			}),
			error: dojo.hitch(this, function(err){
				this._cometd._polling=false;
				var metaMsg = {
					failure: true,
					error: err,
					advice: this._cometd._advice
				};
				this._cometd._publishMeta("connect",false, metaMsg);
				this._cometd._backoff();
				this.tunnelCollapse();
			})
		};

		var connectTimeout=this._cometd._connectTimeout();
		if (connectTimeout>0) {
			post.timeout=connectTimeout;
		}

		this._poll = dojo.rawXhrPost(post);
	}

	this.sendMessages = function(messages){
		for(var i=0; i<messages.length; i++){
			messages[i].clientId = this._cometd.clientId;
			messages[i].id = ""+this._cometd.messageId++;
			messages[i]=this._cometd._extendOut(messages[i]);
		}
		return dojo.rawXhrPost({
			url: this._cometd.url||dojo.config["cometdRoot"],
			handleAs: this._cometd.handleAs,
			load: dojo.hitch(this._cometd, "deliver"),
			postData: dojo.toJson(messages),
			contentType: "text/json;charset=UTF-8",
			error: dojo.hitch(this, function(err){
				this._cometd._publishMeta("publish",false,{messages:messages});
			}),
			timeout: this._cometd.expectedNetworkDelay
		});
	}

	this.startup = function(handshakeData){
		if(this._cometd._status=="connected"){ return; }
		this.tunnelInit();
	}

	this.disconnect = function(){
		var message = {
			channel: "/meta/disconnect",
			clientId: this._cometd.clientId,
			id:	"" + this._cometd.messageId++
		};
		message = this._cometd._extendOut(message);
		dojo.rawXhrPost({
			url: this._cometd.url || dojo.config["cometdRoot"],
			handleAs: this._cometd.handleAs,
			postData: dojo.toJson([message]),
			contentType: "text/json;charset=UTF-8"
		});
	}

	this.cancelConnect = function(){
		if(this._poll){
			this._poll.cancel();
			this._cometd._polling=false;
			this._cometd._publishMeta("connect",false,{cancel:true});
			this._cometd._backoff();
			this.disconnect();
			this.tunnelCollapse();
		}
	}
}

dojox.cometd.longPollTransport = dojox.cometd.longPollTransportJsonEncoded;

dojox.cometd.connectionTypes.register("long-polling", dojox.cometd.longPollTransport.check, dojox.cometd.longPollTransportJsonEncoded);
dojox.cometd.connectionTypes.register("long-polling-json-encoded", dojox.cometd.longPollTransport.check, dojox.cometd.longPollTransportJsonEncoded);


}