Callback Notifications

Callback notifications provide real-time payment status updates to your system. This guide explains how to handle and verify callback requests.

🔄 Callback Process

Sandbox Environment

• Create sandbox order
• Click Set Callback to simulate success/failure
• Important: Payment method must not be empty
• Test callback handling in your system

Production Environment

• Callbacks are sent automatically when actual payments occur
• No manual intervention required
• Real-time payment status updates

API Orders Only

Callbacks are only sent for orders created via API. Orders created through merchant platform payment links cannot be linked to merchant systems.

🔐 Callback Signature Verification

Signature Generation

X-SIGNATURE = SHA256withRSA(smilepayz_private_key, stringToSign)

String to Sign

stringToSign = tradeNo + "|" + X-TIMESTAMP

Verification Process

1. Extract X-SIGNATURE and X-TIMESTAMP from callback headers
2. Construct stringToSign using tradeNo and X-TIMESTAMP
3. Use SmilePayz public key to verify signature
4. Return SUCCESS string if verification passes

Response

When receiving callback requests, simply return:

SUCCESS

📋 Implementation Steps

1. Get Platform Public Key: Refer to Integration Info
2. Verify Signature: Use the signature verification method from Tools Documentation
3. Process Callback: Handle payment status updates
4. Return Response: Send SUCCESS confirmation

⚠️ Important Notes

• Signature Verification: Always verify callback signatures
• Public Key: Use correct platform public key for verification
• Response: Return SUCCESS string only
• Security: Never trust unverified callbacks