Intergrated American Express card online card processing facility through Nations Trust Bank (NTB) Sri Lanka.
Of the few methods of intergration, we used the Hosted Checkout procedure along with our custom built PHP based back end. Also built the backend to log success/failed transactions, status, errors, etc along with an automated receipt emailing service. However compared to the previous experiences with other IPG's, in this method the IPG allows the API/Code to know if the transaction was a success or not only, more details about the transaction are available on their merchant portal.
Successfully supported a client in troubleshooting and setting up the Amex Payment Gateway into their Wordpress or Woocommerce website with fewer calls to Nations Trust Bank.