Hi KillBill-Team,
I have implemented support for SEPA (Single Euro Payments Area) direct debit payments in the Stripe plugin.
SEPA requires an automatic capture instead of a manual capture as it is currently implemented for credit cards. So instead of executing an authorization which is later voided (via the Payment Intents API) I needed to use the Setup Intents API where you can setup a payment method that can then be used at a later time. I have also switched the current credit card flow from the Payment Intents API to use the Setup Intents API.
All tests are still working. I've run the tests with a US-based Stripe account (which cannot use SEPA payments) and with a European account (where credit card and SEPA payments were tested in the HPP flow).
Please let me know if you would like to see this change integrated upstream. I could also send a PR and we continue to discuss it on GitHub - just wanted to know upfront if you are interested.
Best
Soeren