Script to send email by gmail using current user account

send-email-by-gmail-using-current-user-account.js

var nodemailer = require('nodemailer'),
    env = require('../env');

var Service = module.exports = function () {};

Service.prototype.sendByCurrentUserEmailAccount = function(opt, user) {
  var smtpTransport = nodemailer.createTransport('SMTP', {
    service: 'Gmail',
    auth: {
      XOAuth2: {
        user: user.email,
        clientId: env.config.google.clientID,
        clientSecret: env.config.google.clientSecret,
        refreshToken: user.googleRefreshToken
      }
    }
  });

  if (!Array.isArray(opt.to)) opt.to = [opt.to];

  var mailOptions = {
    from: opt.from,
    to: opt.to,
    subject: opt.subject,
    generateTextFromHTML: true,
    html: opt.html
  };

  smtpTransport.sendMail(mailOptions, function(err) {
    if (err) console.log(err);
    smtpTransport.close();
  });
};