How to upload a file in NodeJS without Express - node.js

Question

I'm trying to pick up a file from a form and save it to myself on disk in any folder. I would like to do it by sockets, but I do not know how to handle it. Can someone help me?
This is my code:
main.js
var http = require('http');
var fs = require('fs');
var io = require('socket.io');
var path = require('path');
var server = http.createServer(function (req, res) {
fs.readFile(__dirname + '/index.html', function (err, data) {
if (err) {
res.writeHead(200, {'Content-Type': 'text/html'});
res.write("Not Found");
res.end();
} else {
res.write(data, 'utf8');
res.end();
}
});
}).listen(8000);
var listener = io.listen(server);
listener.sockets.on('connection', function (socket) {
console.log("Connected");
socket.on('disconnect', function () {
console.log("Disconnect");
});
socket.on('form.message', function (data) {
// here to handle the file ??
socket.emit('new.message', {msg: data});
});
});
index.html(client)
<script>
$(function () {
var socket = io.connect();
var $messageForm = $('#messageForm');
var $file = $('#file');
var $outputFile = $('#outputFile');
var obj = {
file: $file.val(),
};
e.preventDefault();
console.log(obj);
socket.emit('form.message', obj);
$file.val('');
socket.on('new.message', function (data) {
$outputFile.append('<div class="well">' + data.msg.file + '</div>');
});
});
</script>