Apple pay on the web backend

Hello, I am integrating Apple Pay on my web page and the full process work At the moment, the only backend call I have is onvalidatemerchant to create my merchant session.

I would like to check transaction details, refund and unsubscribe recurring payment from backend but I can not found any documentation

For example onpaymentauthorized I would like to call my backend to check if the transaction is ok using the transactionIdentifier and update my database, but I am not able to find any documentation about that

Apple pay on the web backend
 
 
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