Log into Facebook using cookies

Session.js

'use strict'

let Promise = require('bluebird');
let fs = Promise.promisifyAll(require('fs'));
let Cheerio = require('cheerio');
let Request = require('request');
let ToughCookie = require('tough-cookie');

class Session {

  constructor(useragent) {
    this.ua = useragent;
    this.fbdtsg = null;
    this.uid = null;
  }

  dtsg() {
    return new Promise((resolve, reject) => {
      if(this.request === null) {
        reject(new Error("self.request is not set. Are you logged in?"));
        return;
      }

      this.request('https://facebook.com', (err, resp, body) => {
        if(err) {
          reject(new Error(err));
          return;
        }

        let match = /name="fb_dtsg" value="([A-Za-z0-9-_:]+)"/.exec(body);
        if(match == null) {
          reject(new Error("Failed to parse fb_dtsg"));
          return;
        }

        resolve(match[1]);
      })
    })
  }

  parseEditThisCookieJSON(file) {
    return new Promise((resolve, reject) => {
      fs.readFileAsync(file).then((data) => {
        let cookies = [];
        let JSONCookies;

        // Catch any errors when parsing JSON
        try {
          JSONCookies = JSON.parse(data);
        } catch(err) {
          reject(new Error(err));
          return;
        }

        // Loop through each cookie in the JSON object adding them to a cooikes array
        JSONCookies.forEach(cookie => {
          let extensions = [
            'session=true',
            'sameSite=no_restriction'
          ];

          if(cookie.expirationDate) {
            extensions.push('expirationDate=' + cookie.expirationDate)
          }

          cookies.push(new ToughCookie.Cookie({
            key: cookie.name,
            value: cookie.value,
            secure: cookie.secure || false,
            path: cookie.path,
            httpOnly: cookie.httpOnly || false,
            extensions: extensions
          }));

          // Set the uid property of object with users ID
          if(cookie.name === 'c_user') {
            this.uid = cookie.value;
          }
        })

        resolve(cookies);
      })
    })
  }

  setCookies(cookies) {
    let cookieJar = Request.jar();

    return new Promise((resolve, reject) => {
      this.parseEditThisCookieJSON(cookies).then(cookies => {
        cookies.forEach(function(cookie) {
          cookieJar.setCookie(cookie, 'https://facebook.com', (err, cookie) => {
            if(err) {
              reject(new Error(err));
              return;
            }
          })
        })

        this.request = Request.defaults({
          jar: cookieJar, headers: { 'User-Agent': this.ua }
        });

        this.dtsg().then(dtsg => {
          this.fbdtsg = dtsg;
          resolve(true);
        })
      })
    })
  }
}

module.exports = Session;