simple nodejs script to handle/listen callback

server.js

const express = require('express'); 
const bodyParser = require('body-parser');
const app = express();
 
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
  extended: true,
}));
 
// assume callback url is: http://localhost:3000/event
app.post('/event', (req, res) => {
 
  res.send('OK');
  // handle the data sent from callback here
  console.log(req.body)
});
 
const portToListenOn = 3000;
 
app.listen(portToListenOn, () => {
  console.log(`Listening callback notif on port ${portToListenOn}. Started ${new Date().toString()}`);
});