sending Email using nodemailer with gmail credential

// https://myaccount.google.com/lesssecureapps
var nodemailer = require('nodemailer');

var smtpTransport = require('nodemailer-smtp-transport');

var transporter = nodemailer.createTransport(smtpTransport({

service: 'gmail',
host: 'smtp.gmail.com',
auth: {
user: 'gmail email address',
pass: 'pass'
}
}));

var mailOptions = {
from: '',
to: '',
subject: 'Sending Email using Node.js[nodemailer]',
text: 'That was easy!'
};

transporter.sendMail(mailOptions, function(error, info){
if (error) {
console.log(error);
} else {
console.log('Email sent: ' + info.response);
}
});

ref = https://codeburst.io/sending-an-email-using-nodemailer-gmail-7cfa0712a799
ref2 = https://nodemailer.com/smtp/