Goal: deduct a customer’s points (stored in a customer metafield—custom data attached to a resource) immediately upon a successful checkout to prevent double-spending (e.g., two devices ordering simultaneously).
Flow described: discount applied at the first checkout step. The need is to update the customer metafield in real time once the order is processed.
Proposed approach reviewed: useApplyMetafieldsChange in a Checkout UI extension can mutate checkout metafields (data tied to the checkout/order), not customer metafields. This means it won’t update the customer’s stored points directly at checkout.
Current limitation: updating customer metafields from within Checkout UI extensions isn’t supported/confirmed possible in this thread.
Workaround adopted: save order details to an external database at checkout, then update the customer metafield later via an automated API process (not real-time, e.g., next day).
Status: No built-in real-time method confirmed for updating customer metafields during/at checkout. Thread concludes with a deferred update workaround; the real-time fraud-prevention need remains unresolved in-thread.
Hi Nhtbao101,
Just to understand your use-case fully - do you want to update the customer metafield during the checkout process, or after - ie: once the order is processed? When do you want the discount to be applied?
Once I have a little bit more info I can recommend the best approach!