gistfile1.js

var fs = require('fs');
var http = require('http');
var urlparser = require('url');
var k = process.binding('constants');

function Download(url,path){
	this.u= urlparser.parse(url);
	this.httpStatus=null;
	this.recievedHeader=null;
	this.filestats = {filesize: null, bytesWritten: 0, bytesRecieved: 0}
	this.timer = {timerObject: null, timerInterval: 2000}
	this.fd = null;

	
	this.Download(url,path);
}

Download.prototype = {
	Download: function (url,path){	
		fs.open(path, k.O_WRONLY | k.O_CREAT, 0666, function(err, fd){
			if(err){
				console.error("Got error while opening file: " + err.message);
				process.exit(1); 
			}
			this.fd=fd;
			this.startDownload();
		});
	},
	startDownload: function(){
		var options={host: this.u.host, port: this.u.port ||'80', path: this.u.pathname, method: 'GET'};
		var g=http.get(options);
		g.on('response', function(res) {
			console.log('got response: ' + res.statusCode);
			this.recievedHeader=res.headers;
			this.httpStatus=res.statusCode;

			res.on('data',onNewData);
		});
		g.on('error', function(e) {
			console.log('got error while sending get request: ' + e.message);
			process.exit(2);
		});
		g.on('end', function() {
			console.log('download complete');
		});
	},
	onNewData: function(chunk){
		this.filestats.bytesRecieved += chunk.length;
		fs.write(fd, chunk, 0, chunk.length, null, function(err, written){
			this.filestats.bytesWritten += written;
			if( (this.filestats.filesize == this.filestats.bytesWritten || this.terminate) 
				&& this.filestats.bytesWritten == this.filestats.bytesRecieved){
				fs.close(fd);
				console.log('all bytes written');
			}
		});
	}
}

var d = new Download('http://dl.google.com/earth/client/current/GoogleEarthLinux.bin', 'googleearth.bin');