SO Login using node.js

gistfile1.js

var http = require('http'),
    https = require('https'),
    jsdom = require('jsdom'),
    url = require('url'),
    req;

req = http.request({
    method: 'POST',
    host: 'stackoverflow.com',
    path: '/users/signin',
    port: 80,
    headers: {
        Accept: '*/*',
        Cookie: 'gauthed=1'
    }
}, function(res) {
    var chunk = '';

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

    res.on('end', function() {
        callForm(chunk);
    });
});

req.on('error', function(e) {
    console.log(e.message);
});

req.end();

// Get the form
function callForm(formUrl) {
    var req = https.get(formUrl, function(res) {
        var chunk = '';

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

        res.on('end', function() {
            jsdom.env(chunk, function(err, window) {
                var fkey = window.document.getElementById('fkey').value;
                login(res.headers['set-cookie'], fkey);
            });
        });
    });

    req.end();
}

// Submit the form
function login(cookies, fkey) {
    var e = encodeURIComponent;
    var data = 'email=' + e('florian+2@margaine.com') + '&password=' +
        e('somepass') + '&affId=4&fkey=' + fkey;

    var opts = {
        method: 'POST',
        host: 'openid.stackexchange.com',
        path: '/affiliate/form/login/submit',
        headers: {
            'Content-Length': data.length,
            'Content-Type': 'application/x-www-form-urlencoded',
            'Cookie': 'gauthed=1;'
        }
    };

    cookies.forEach(function(cookie) {
        opts.headers.Cookie += cookie + ';';
    });

    var req = https.request(opts, function(res) {
        var chunk = '';

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

        res.on('end', function() {
            jsdom.env(chunk, function(err, w) {
                var anchor = w.document.querySelector('noscript a'),
                    link = anchor.href;

                authenticate(res.headers['set-cookie'], link);
            });
        });
    });

    req.on('error', function(e) {
        console.log(e.message);
    });

    req.write(data);
    req.end();
}

// Follow the redirection links till the end and keep the cookies
function authenticate(cookies, link) {
    link = url.parse(link);

    var opts = {
        method: 'GET',
        host: link.host,
        path: link.path,
        headers: { Cookie: '' }
    };

    cookies.forEach(function(cookie) {
        opts.headers.Cookie += cookie + ';';
    });

    if (!/gauth/.test(opts.headers.Cookie)) {
        opts.headers.Cookie += 'gauthed=1';
    }

    var scheme = link.protocol === 'http:' ? http : https;
    var req = scheme.request(opts, function(res) {
        var loc;
        if (res.statusCode === 302 || res.statusCode === 301) {
            loc = res.headers.Location || res.headers.location;
            authenticate(cookies, loc);
            return;
        }
        var chunk = '';

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

        res.on('end', function() {
            console.log(cookies);
        });
    });

    req.end();
}