Get Facebook access token with only backend node.js

data.json

{
  "email": "[email protected]",
  "pass": "",
  "client_id": "",
  "client_secret": "",
  "redirect_uri": "http://localhost:3000"
}

fb-authenticator.js

var url = require('url');
var https = require('https');
var queryString = require('querystring');
var fs = require('fs');

var client_id, client_secret, redirect_uri;

function getCookies(email, password, callback) {

    var data = queryString.stringify({'email': email, 'pass': password, 'default_persistent': '1', 'timezone': '-120'});

    var fbGetCookieHeaders = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36',
        'Cookie': '_js_reg_fb_gate=null',
        'Host': 'www.facebook.com',
        'Content-Type': 'application/x-www-form-urlencoded',
        'Content-Length': Buffer.byteLength(data)
    };

    var fbGetCookieOptions = {
        protocol: 'https:',
        hostname: 'www.facebook.com',
        path: '/login.php?login_attempt=1&lwv=110',
        method: 'POST',
        headers: fbGetCookieHeaders
    };

    function findCookie(name, cookies) {
        return new RegExp(name + '=(.+?);').exec(cookies)[1];
    }

    var req = https.request(fbGetCookieOptions, (res) => {
        var cookies = res.headers['set-cookie'].toString();
        var c_user = findCookie('c_user', cookies);
        var xs = findCookie('xs', cookies);
        callback({c_user: c_user, xs: xs});
    });

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

function logIn(cookies, callback) {

    var fbHeaders = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36',
        'Cookie': 'c_user=' + cookies.c_user + '; xs=' + cookies.xs,
        'Host': 'www.facebook.com'
    };

    var fbOptions = {
        protocol: 'https:',
        hostname: 'www.facebook.com',
        path: '/dialog/oauth?client_id=' + client_id + '&redirect_uri=' + redirect_uri,
        headers: fbHeaders
    };

    https.request(fbOptions)
        .on('response', (response) => {
            var loginCode = url.parse(response.headers.location, true).query.code;
            callback(loginCode);
        })
        .end();
}

function getAccessToken(loginCode, callback) {

    var graphHeaders = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36',
        'Host': 'graph.facebook.com'
    };

    var graphOptions = {
        protocol: 'https:',
        hostname: 'graph.facebook.com',
        path: '/v2.3/oauth/access_token?client_id=' + client_id + '&redirect_uri=' + redirect_uri + '/&client_secret=' + client_secret + '&code=' + loginCode,
        headers: graphHeaders
    };

    https.request(graphOptions, (response) => {

        response.on('data', function (chunk) {

            callback(JSON.parse(chunk.toString('utf-8')).access_token);
        });
    }).end();
}

fs.readFile('data.json', 'utf-8', (err, data) => {
    var dataObj = JSON.parse(data);
    client_id = dataObj.client_id;
    client_secret = dataObj.client_secret;
    redirect_uri = dataObj.redirect_uri;
    getCookies(dataObj.email, dataObj.pass, receivedCookies);
});

function receivedCookies(cookies) {
    logIn(cookies, loggedIn);
}

function loggedIn(loginCode) {
    getAccessToken(loginCode, receivedToken);
}

function receivedToken(accessToken) {
    console.log(accessToken);
}