Adding timeout support for http request in Node.JS

This is HttpUtil Module, you need "require" it before using the module.

var http= require("http");

var HttpUtil = function(){
	var namespace = {
		Get: function(options, timeout, callback){
			var timer=null;
			var req = null;
			var hasCallBackCalled =false;
			// set timeout, it will cancel the request if there is a timeout
			timer = setTimeout(function(){
				if(req!=null)
					req.abort();
				if(!hasCallBackCalled &&  callback){
					hasCallBackCalled=true;
					var errObj = new HttpResult(true, "Request Timeout!", null);
					callback(errObj);
				}
			}, timeout);

			req = http.get(options, function(res){

			      clearTimeout(timer);
			      var chunks=[],length=0;

			      res.on("data", function(chunk){
					length += chunk.length;
					chunks.push(chunk);
			      });

			      res.on("end", function(){
				  var data =chunks==null? null: chunks.toString();
				  if(!hasCallBackCalled && callback){
					hasCallBackCalled=true;
					var errObj = new HttpResult(false, null, data);
					callback(errObj);
				  }
			      });

			}).on("error", function(e){
				clearTimeout(timer);
				if(!hasCallBackCalled &&  callback){
					hasCallBackCalled=true;
					var errObj = new HttpResult(true, e.message, null);
					callback(errObj);
				}
			});
		},
		Post: function(options, postData, timeout, callback){
			var timer=null,
			    req = null,
			    hasCallBackCalled =false;
			
			// set timeout, it will cancel the request if there is a timeout
			timer = setTimeout(function(){
				if(req != null)
					req.abort();
				if(!hasCallBackCalled &&  callback){
					hasCallBackCalled=true;
					var errObj = new HttpResult(true, "Request Timeout!", null);
					callback(errObj);
				}
			}, timeout);
			
			req= http.request(options, function(res){
				//res.setEncoding('utf-8');
				clearTimeout(timer);
				var data = '';

				res.on('data',function(chunk){
					data += chunk;
				});

				res.on('end',function(){
					  if(!hasCallBackCalled && callback){
						hasCallBackCalled=true;
						var errObj = new HttpResult(false, null, data);
						callback(errObj);
					  }
				});
	
			}).on('error',function(e){
				clearTimeout(timer);
				if(!hasCallBackCalled &&  callback){
					hasCallBackCalled=true;
					var errObj = new HttpResult(true, e.message, null);
					callback(errObj);
				}
			});

			req.write(postData);
		}
	};
	return namespace;
}();

/* HttpResult is the object when finished the request.
   hasError: Indicate whether there is an error when performing a request.
   errorMessage: If hasError is true, you can get error message here.
   data: If there is no error, you can get the data from the request.
*/
function HttpResult(hasError, errorMessage, data){
	this.hasError=hasError;
	this.errorMessage = errorMessage;
	this.data=data;
}

/*Export the function to public*/
module.exports = HttpUtil;

Below is the usage for above module.

var HttpUtil = require("./HttpUtility");
var querystring =require("querystring");

function process(e){
	console.log(e.data);
	console.log(e.hasError);
	console.log(e.errorMessage);
}
/********************this is getting data***********************************
var options={
	host: "www.google.com",
	port: 80
};

HttpUtil.Get(options, 5000, process);

/********************this is posting data***********************************/
var jsonData={
	txtbill:"1234567"
};

var postData = querystring.stringify(jsonData);

var options={
	host: "www.zto.cn",
	method: "POST",
	path: "http://www.zto.cn/bill.aspx",
	headers:{
		'Content-Type': 'application/x-www-form-urlencoded',
		'Content-Length': postData.length
	}
};

HttpUtil.Post(options, postData, 5000, process);