I've spent time looking over the APIs and looking at various questions but I want to post this to try and get a direct yes/no.
I know Shopify added support for selling plans in the Storefront Cart API but that requires you send the user to a web link to checkout. They have not added any such support for selling plans in the Storefront Checkout API, that leads me to believe it isn't possible to build an entirely headless checkout experience for subscriptions.
Is it possible to provide a completely headless checkout with Shopify Subscriptions?
For context I've looked at the various APIs for subscriptionContractCreate and notice it requires payment method Id, does that mean I would have to use the admin graphql api to create a customer, create a payment method for that customer to be able to create a subscriptionContract? Rather then the payment token returned when vaulting a card for completing a checkout using the Storefront API.
Any help here would be greatly appreciated, I feel like it should be possible given the APIs I see available.
Sorry, it is not possible to do a completely headless checkout at the moment. We do require that you go through the storefront API and redirect the customer to a web checkout form to complete a checkout.