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Server-to-server processing is a payment option that allows merchants to perform transactions and interact with the payment system without involving the end-user directly. It is commonly used for various scenarios such as recurring payments, refunds, de-registering payment methods, capturing or voiding previous preauthorizations, and SEPA DirectDebit transactions.

Use cases

Processing flow

  1. The transaction is triggered, for example by a customer using a stored credit card.
  2. Merchant
    The merchant sends the appropriate API call —for example a debit or refund request— to the IXOPAY platform.
  3. The IXOPAY platform processes the request and sends a transaction request to the PSP.
  4. The PSP processes the transaction and sends the result back to IXOPAY platform.
  5. Merchant
    The IXOPAY platform processes the PSP's response and, using the callbackUrl field, notifies the merchant via a callback to the URL provided in the initial API call. This callback includes the payment status and any relevant details.
  6. Merchant
    The merchant handles the callback, it is recommended to store the transaction's uuid for future use.
  7. Merchant
    The merchant responds to the callback with:
    Callback response
    HTTP/1.1 200 OK
    Content-Type: text/plain

  8. The IXOPAY platform responds to the merchant backend with a request containing the status of the transaction, usually FINISHED, PENDING or ERROR.
  9. Merchant
    The merchant decides what page to display to the customer depending on the transaction status.

Here's a visual representation of the processing flow using a sequence diagram: