Make Mollie payments that don't require interaction (follow-up payments) asynchronous?

[remcotolsma]

https://github.com/wp-pay-gateways/mollie/blob/a65e919f6228483c5672be6bdfdb3ae64342975f/src/Gateway.php#L463-L464

When we make these create payment requests asynchronous it's easier to retry them?

Code	Description
429	Too Many Requests – Your request has hit a rate limit. Please wait for a bit and retry.

https://docs.mollie.com/overview/handling-errors

I also mentioned Mollie error handling als in this issue: https://github.com/pronamic/wp-pronamic-pay/issues/188#issuecomment-907155800.

The follow-up payments that could not be started could be put in a queue.

Maybe https://actionscheduler.org/ (https://github.com/pronamic/wp-pronamic-pay/issues/253) can help us to make it easier to reschedule those actions.

• https://github.com/woocommerce/action-scheduler/issues/234
• https://lihautan.com/retry-async-function-with-callback-promise/
• https://github.com/guzzle/promises
• https://github.com/spatie/async
• https://github.com/reactphp/promise
• https://github.com/SGrondin/bottleneck

[rvdsteege]

Possibly related / for reference:

• https://docs.adyen.com/development-resources/api-idempotency
• https://en.wikipedia.org/wiki/Exponential_backoff

[remcotolsma]

Nice catch, i didn't know the term idempotent:

• https://stripe.com/docs/api/idempotent_requests
• https://en.wikipedia.org/wiki/Idempotence
• https://github.com/stripe/stripe-php/blob/3b424712a4e0bc0400a744cee34785f81a23fba5/lib/HttpClient/CurlClient.php#L236-L242
• https://github.com/stripe/stripe-php/blob/3b424712a4e0bc0400a744cee34785f81a23fba5/lib/HttpClient/CurlClient.php#L348-L471
• https://github.com/Adyen/adyen-php-api-library/blob/6727f47f1df98df64fb7c4be687cda70ba919905/src/Adyen/HttpClient/CurlClient.php#L89-L92

[remcotolsma]

We have (partly) implemented this in https://github.com/wp-pay-gateways/mollie/blob/19a60e2d5ad3ee8ca7466f0cad78d666d59179d1/src/Gateway.php#L450-L494. In case of exceptions in checking/creating a Mollie user or mandate, there may still be room for improvement.