URL Shortener

main.js

var mongoose 	= require('mongoose');
var http 			= require('http');

mongoose.connect("mongodb://localhost/shortener");
var db 				= mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function() {

	var urlSchema = mongoose.Schema({
		slug: String,
		url: String
	});
	shortener 		= mongoose.model("shortener", urlSchema);

});

var server 		= http.createServer( function(httpRequest, httpResponse) {

	var now 	= new Date();
	var urls 	= httpRequest.url.split("/");
	var parts	= [];
	for(var i = 0; i < urls.length; i += 1) {
		if(urls[i] === "") continue;
		parts.push(urls[i]);
	}


	if( parts.length === 0 ||
			( parts.length === 1 && parts[0] === 'favicon.ico' ) ) {

		console.log("replied with http 400");
		httpResponse.writeHead( 400 );
		httpResponse.end( "Invalid Request" );

	} else if( parts.length === 2 ) {

		//This is a set
		shortener.find( {
			url: parts[1]
		}, function(error, oldUrl) {

			if(error) throw error;

			if(oldUrl.length === 0) {

				var shortUrl = new shortener({
					slug: now.getTime().toString(36),
					url: decodeURIComponent(parts[1])
				});

				shortUrl.save( function(error, newUrl) {

					var result = { 
						shortUrl: "http://" + httpRequest.headers.host + '/' + newUrl.slug
					};

					httpResponse.writeHead( 200, {
						'Content-Type': 'application/json'
					} );
					httpResponse.end( JSON.stringify(result) );

				} );

			} else {

				console.log("fetching old url");
				console.log(oldUrl);

				var result = { 
					shortUrl: "http://" + httpRequest.headers.host + '/' + oldUrl.slug
				};

				httpResponse.writeHead( 200, {
					'Content-Type': 'application/json'
				} );
				httpResponse.end( JSON.stringify(result) );

			}

		} );

	} else if( parts.length === 1 ) {

		//This is a get
		shortener.find( {
			slug: parts[0]
		}, function(error, oldUrl) {

			console.log("redirect to url");
			console.log(oldUrl[0].url);
			httpResponse.writeHead( 302, {
				'Location': oldUrl[0].url
			} );

		} );

	}

} ).listen(7000);