app.js

const express = require('express');
const path = require('path');
const exphbs = require('express-handlebars');
require('dotenv').config();
//const stripe = require('stripe');
const stripe = require('stripe')(process.env.STRIPE_SECRET_KEY);

var app = express();

// view engine setup (Handlebars)
app.engine('hbs', exphbs({
  defaultLayout: 'main',
  extname: '.hbs'
}));
app.set('view engine', 'hbs');
app.use(express.static(path.join(__dirname, 'public')));
app.use(express.urlencoded({ extended: true }))
app.use(express.json({}));

/**
 * Home route
 */
app.get('/', function(req, res) {
  res.render('index');
});

/**
 * Checkout route
 */
app.get('/checkout', async (req, res) => {
  // Just hardcoding amounts here to avoid using a database
  const item = req.query.item;
  let title, amount, error,client_secret;

  switch (item) {
    case '1':
      title = "The Art of Doing Science and Engineering"
      amount = 2300      
      break;
    case '2':
      title = "The Making of Prince of Persia: Journals 1985-1993"
      amount = 2500
      break;     
    case '3':
      title = "Working in Public: The Making and Maintenance of Open Source"
      amount = 2800  
      break;     
    default:
      // Included in layout view, feel free to assign error
      error = "No item selected"      
      break;
  }

   // add payment intent
   const paymentIntent = await stripe.paymentIntents.create({
    amount: amount,
    currency: 'usd',
    automatic_payment_methods: {enabled: true},
    //payment_method_types: ['card'],
   });
   client_secret = paymentIntent.client_secret;

  res.render('checkout', {
    title: title,
    amount: amount,
    error: error,
    client_secret: client_secret
  });
});

/**
 * Success route
 */
app.get('/success', function(req, res) {
  res.render('success');
});

/**
 * Get the publishable key
 */
 app.get('/publishable', function(req, res) {
  res.json({publishablekey: process.env.STRIPE_PUBLISHABLE_KEY})
});

/**
 * Start server
 */
app.listen(3000, () => {
  console.log('Getting served on port 3000');
});