Add the option to not setup payment methods for future usage

Ahh, I see - the field is indeed optional. However, let's use this ticket to solve this for both the Card Element and the Payment Element. Note that in either case, we also need to ensure the payment method entity created in Drupal Commerce is set to non-reusable when this "none" option is selected.

Additionally, as a slight clarification to the option, given the name of the field, let's make this the third option, not the first, with a key of single_use and label of, "Single use: the payment method will not be made available for subsequent transactions".

Good find! I was actually wondering about that message myself when testing other issues just now. 😛

I've opened MR with the initial work for both payment gateways. But it still requires some additional work and testing. We need to figure out if we need to create a remote payment method if None (or Single use) is selected and attach it to the remote client or not.

After some research, I see the following.
For the Stripe Card Element, this works perfectly - the PaymentIntent succeeded and the payment method was attached to the customer with no "Set up for future use" options.
For the Stripe Payment Element, it still doesn't work - the PaymentIntent succeeded but I get an error "This PaymentMethod was previously used without being attached to a Customer or was detached from a Customer, and may not be used again.". This means that we want to attach the payment method to the customer after the paymentIntent has used it, so this should happen before that. In our case, it is impossible because it does not exist.

So basically when we use the setup_future_usage parameter, the paymentIntent automatically attaches the payment method to the customer, but in case it is empty or missing, we need to attach it to the customer manually. In the case of the Stripe Payment Element, the payment method will be created after the paymentIntent is confirmed, but at this point, we cannot attach it to the customer because it has already been used by the paymentIntent.

I'm open to discussion if anyone is also interested in this issue.

From my comment we cannot attach a payment method to the customer after the paymentIntent is confirmed but we can skip attaching a payment method to the customer. But in this case, the Stripe dashboard on the customer page won't show the payment method (is that a big deal?). Otherwise, for the Stripe Card Element, the payment method will be there.
This seems to be the only way we can use the Stripe Payment element.

https://www.drupal.org/project/commerce_stripe/issues/3392413#mr56-note2... works, I can see the new option "Single use: the payment method will not be made available for subsequent transactions" under Stripe Payment Element payment gateway. When choosing it, I can see single-use payment methods showing up, although they don't actually work, that's new issues.

Can we get this in first, so follow up issues can fix additional problems.

I brought the latest changes from 8.1-1.x to this MR.

However, I temporarily removed the changes to Stripe.php

In #3, @rszrama wanted to add this third option for Card Element. But, Card Element uses Stripe Card Element (Stripe.php) gateway, which doesn't have on-session and off-session configurations.

@vmarchuk made this 3rd option available to Card Element by using the configuration from Stripe Review Pane. Programming wise, add a condition or dependency on routing makes Stripe.php less robust, as routing isn't always safe assumption. Personally, I think if we want the Card Element to have this configuration, then we want to add this configuration to its gateway. The configuration for Stripe Review Pane serves as an option to override in the checkout process.

What do you think?

Here is one more thing we have to deal with: when a payment succeeded, we have the logic to create a customer and attach the payment method in both Stripe.php and StripePaymentElement.php.

However, when we set setup_future_usage: null to make/allow single-use payment method. We cannot create the customer and attach the single-use payment method. Otherwise, Stripe API will return:

400 invalid_request_error
This PaymentMethod was previously used without being attached to a Customer or was detached from a Customer, and may not be used again.

This is documented here https://stripe.com/docs/payments/payment-methods#usage

Single-use payment methods (for example, some kinds of bank transfers) can’t be attached to customers because they’re consumed after a payment attempt.

So, depending on the gateway, we will conditionally attach the payment method that just completed.

In https://www.drupal.org/project/commerce_stripe/issues/3392413#mr56-note2..., I added a condition.

Coming from #3403745-4: Update Stripe API Version, I've tried this patch (latest MR) and it solved our problem :-)

Hi there,
I'd like to add some info to the mix that needs to be taken into account about setup_future_usage:
#3414706: Do not set setup_future_usage off_session again for already stored payment methods to avoid multiple mandates creation

The MR needs to be rebased, its no longer applying for me.

Rebased patch with the latest changes from 8.x-1.x.
+ tested changes locally and everything works as expected.
@skyredwang
I just don't know why we need a new test in tests/src/FunctionalJavascript/CheckoutTest.php since all the tests were written for the Stripe Card Element, but as part of this issue, we are only making changes for the Stripe Payment Element.