Formanowicz.js

const nodemailer = require('nodemailer');
const request = require('request');

var transporter = nodemailer.createTransport({
        host: 'smtp.gmail.com',
        port: 587,
        secure: false,
        auth: {
            user: 'login',
            pass: 'password'
        }
    });

    var mailOptions = {
        from: '"Forman" <example@gmail.com>',
        to: 'example@gmail.com',
        subject: 'Wyniki egzaminu z matemayki dyskretnej',
        html: '<a>http://www.cs.put.poznan.pl/pformanowicz/students.html</a>'
    };

    function notify()
    {
      transporter.sendMail(mailOptions, (error, info) => {
          if (error) {
              return console.log(error);
          }
          console.log(`Mail sent to ${mailOptions.to}`);

      });
    }

    const options = {
    url: 'http://www.cs.put.poznan.pl/pformanowicz/students.html',
    method: 'HEAD'
    };

    var lastModified;
    request(options, (err, res, body)=>{
        lastModified = res.headers['last-modified'];
    });



    var id = setInterval(()=>{
          var tmp;
          request(options, (err, res, body)=>{
              tmp = res.headers['last-modified'];
              console.log("request made");

              if(lastModified != tmp)
              {
                notify();
                clearInterval(id);
              }
          });

    }, 5000);