paymentRequestButton.js

  $.getScript('https://js.stripe.com/v3/', function() {
    var stripe = Stripe(STRIPE_TEST_KEY);

    var paymentRequest = stripe.paymentRequest({
      country: 'US',
      currency: 'usd',
      total: {
        label: 'Demo total',
        amount: 1099,
      },
      requestPayerName: true,
      requestPayerEmail: true,
    });

    var elements = stripe.elements();
    var prButton = elements.create('paymentRequestButton', {
      paymentRequest: paymentRequest,
    });

    // Check the availability of the Payment Request API first.
    paymentRequest.canMakePayment();
    paymentRequest.canMakePayment().then(function(result) {
      if (result) {
        prButton.mount('#payment-request-button');
      } else {
        document.getElementById('payment-request-button').style.display = 'none';
      }
    });

  });