app.js

const express = require('express');
const app = express();
const server = require('http').createServer(app);
const bodyParser = require('body-parser');
const nodemailer = require('nodemailer');
const unirest = require('unirest');
const port = process.env.PORT || 3000;

app.set('view engine', 'ejs');
app.use('/public', express.static('public'));

app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());

app.use((req, res, next) => {
  res.locals.msg = '';
  next();
});

app.get('/', (req, res) => {
  res.render('index');
});

app.post('/send', (req, res) => {
  let output = `
    <h1>New Email!</h1>
     <ul>
       <li>Name: ${req.body.name}</li>
       <li>Email: ${req.body.email}</li>
       <li>Subject: ${req.body.subject}</li>
       <li>Message: ${req.body.message}</li>
     </ul>
  `;
  const message = req.body.message;
  const sender_ip = req.ip;
  // check for spam
  unirest.post("https://oopspam.p.rapidapi.com/v1/spamdetection")
    .header("X-RapidAPI-Host", "oopspam.p.rapidapi.com")
    .header("X-RapidAPI-Key", "YOUR_API_KEY")
    .header("Content-Type", "application/json")
    .send({ "sender_ip": sender_ip, "content": message })
    .end(function (result) {
      console.log(result.status, result.headers, result.body);
      if (result.status != 200) {
        // handle the error
        return console.log(result.body);
      }
      if (result.body.Score < 3) {
        // create reusable transporter object using the default SMTP transport
        let transporter = nodemailer.createTransport({
          host: 'mail.YOURDOMAIN.com',
          port: 587,
          secure: false,
          auth: {
            user: 'YOUREMAIL',
            pass: 'YOURPASSWORD'
          },
          tls: {
            rejectUnauthorized: false
          }
        });
        // setup email data with unicode symbols
        let mailOptions = {
          from: '"Nodemailer Contact" <your@email.com>', // sender address
          to: 'RECEIVEREMAILS', // list of receivers
          subject: 'Node Contact Request', // Subject line
          text: 'Hello world?', // plain text body
          html: output // html body
        };

        // send mail with defined transport object
        transporter.sendMail(mailOptions, (error, info) => {
          if (error) {
            return console.log(error);
          }
          console.log('Message sent: %s', info.messageId);
          console.log('Preview URL: %s', nodemailer.getTestMessageUrl(info));

          res.render('contact', { msg: 'Email has been sent' });
        });
      }
    });

});

server.listen(port, '0.0.0.0', () => console.log(`App running on port ${port}`));