Overview
By embedding ZAFA PAY’s checkout page in an iframe, you can complete payments within your site without redirecting users.
Iframe embedding provides a seamless payment experience while maintaining PCI DSS compliance.
Implementation Steps
1. Create Payment Request
Create a payment request using POST /v1/payments as usual. Get the payment_url from the response.
curl -X POST https://api.sandbox.zafapay.com/v1/payments \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"amount": 1000,
"currency": "usd",
"external_id": "order_12345",
"success_redirect_url": "https://your-site.com/success",
"failure_redirect_url": "https://your-site.com/failure"
}'
2. Embed in iframe
Add the ?mode=embedded parameter to the payment_url and set it in the iframe.
<iframe
src="https://pay.zafapay.com/checkout/req_xxx?token=xxx&mode=embedded"
width="100%"
height="700"
style="border: none;"
allow="payment"
></iframe>
The mode=embedded parameter is required. Without it, a redirect will occur when the payment is completed.
3. Receive postMessage Events
Payment results are sent to the parent window via postMessage.
window.addEventListener('message', function(event) {
// Security: Verify origin
if (event.origin !== 'https://pay.zafapay.com') {
return;
}
const data = event.data;
if (!data || !data.type) return;
switch (data.type) {
case 'PAYMENT_SUCCESS':
console.log('Payment successful:', data.transactionId);
// Handle success
break;
case 'PAYMENT_FAILED':
console.log('Payment failed:', data.error);
// Handle failure
break;
case 'PAYMENT_CANCEL':
console.log('Cancelled');
// Handle cancellation
break;
case 'REDIRECT_REQUIRED':
console.log('Redirect required:', data.url);
// Handle redirect for 3D Secure etc.
window.open(data.url, '_blank');
break;
}
});
Event Types
| Event | Description | Included Data |
|---|
PAYMENT_SUCCESS | Payment successful | transactionId, requestId |
PAYMENT_FAILED | Payment failed | error, code |
PAYMENT_CANCEL | User cancelled | None |
REDIRECT_REQUIRED | Redirect required for 3D Secure etc. | url, reason |
PAYMENT_SUCCESS
Sent when payment completes successfully.
{
"type": "PAYMENT_SUCCESS",
"transactionId": "tx_abc123",
"requestId": "req_xyz789"
}
PAYMENT_FAILED
Sent when payment fails.
{
"type": "PAYMENT_FAILED",
"error": "Card was declined",
"code": "card_declined"
}
PAYMENT_CANCEL
Sent when user clicks “Cancel and return to site”.
{
"type": "PAYMENT_CANCEL"
}
REDIRECT_REQUIRED
Sent when redirect is required for 3D Secure authentication etc.
{
"type": "REDIRECT_REQUIRED",
"url": "https://stripe.com/3ds/...",
"reason": "3ds_required"
}
When redirect is required, open it in a new tab/window or navigate the parent window. Redirects within the iframe may not work due to security restrictions.
Complete Implementation Example
<!DOCTYPE html>
<html>
<head>
<title>Checkout Page</title>
</head>
<body>
<h1>Payment</h1>
<div id="checkout-container">
<!-- iframe will be inserted dynamically -->
</div>
<script>
// Set payment URL (get from backend)
const paymentUrl = 'YOUR_PAYMENT_URL';
// Embed iframe
const container = document.getElementById('checkout-container');
const iframe = document.createElement('iframe');
iframe.src = paymentUrl + (paymentUrl.includes('?') ? '&' : '?') + 'mode=embedded';
iframe.style.width = '100%';
iframe.style.height = '700px';
iframe.style.border = 'none';
iframe.setAttribute('allow', 'payment');
container.appendChild(iframe);
// Event listener
window.addEventListener('message', function(event) {
if (event.origin !== 'https://pay.zafapay.com') return;
const data = event.data;
if (!data || !data.type) return;
switch (data.type) {
case 'PAYMENT_SUCCESS':
alert('Payment completed!');
window.location.href = '/thank-you?tx=' + data.transactionId;
break;
case 'PAYMENT_FAILED':
alert('Payment failed: ' + data.error);
break;
case 'PAYMENT_CANCEL':
if (confirm('Cancel the payment?')) {
window.location.href = '/cart';
}
break;
case 'REDIRECT_REQUIRED':
window.open(data.url, '_blank');
break;
}
});
</script>
</body>
</html>
Security Considerations
Origin Verification
Always verify event.origin when receiving postMessage.
HTTPS Required
Iframe embedding only works on HTTPS sites.
Use with Webhooks
For payment confirmation, always receive and verify webhooks on your server in addition to postMessage.
Testing
When testing in the Sandbox environment, you can use the following test cards.
| Card Number | Result |
|---|
4242 4242 4242 4242 | Success |
4000 0000 0000 3220 | 3D Secure required |
4000 0000 0000 9995 | Declined (insufficient funds) |
4000 0000 0000 0002 | Declined (generic) |
Use any future date for expiry and any 3 digits for CVC.