Simple Node.js static HTTP server

gistfile1.js

function serve(lang, port) {
	if (!lang && o.LANGS.length) lang = o.LANGS[0];
	if (!port) port = 8000;
	var mimeTypes = {
		'default': 'text/plain',
		'.html': 'text/html',
		'.jpg': 'image/jpeg',
		'.png': 'image/png',
		'.js': 'text/javascript',
		'.css': 'text/css'
	};

	var server = http.createServer(function(req, res) {
		var uri = url.parse(req.url).pathname,
			filename;
		if (lang && uri.indexOf('.') === -1) {  // Page
			filename = path.join(o.PUBLISH_DIR, lang, (uri === '/' ? '/index' : uri) + '.html');
		}
		else {  // File
			filename = path.join(o.PUBLISH_DIR, uri);
		}

		path.exists(filename, function(exists) {
			if (!exists) {
				console.log(colors.red('404: ' + uri));
				res.writeHead(404);
				res.end('404: Not found.');
				return;
			}

			console.log('200: ' + uri);
			var mimeType = mimeTypes[path.extname(filename)] || mimeTypes['default'];
			res.writeHead(200, {'Content-Type': mimeType});

			var fileStream = fs.createReadStream(filename);
			fileStream.pipe(res);
		});
	});

	server.on('error', function (e) {
		if (e.code === 'EADDRINUSE') {
			serve(lang, port + 1);
		}
		else {
			error('Error running server.\n' + e.code);
		}
	});

	server.on('listening', function () {
		console.log('Sweet is waiting for you at http://127.0.0.1:%s/', server.address().port);
	});

	server.listen(port);
}