we are already able to prefill the customer data via a post get to the following checkout url:
This works pretty nicly for name, email, etc, but we can't figure out how I can set metafields with this request.
What is our intention?
-> We want to prefill the address for the customer (a pickup place) and also store the the ID of this pick up place in a metafiled (or any other hidden field)
Any ideas on how this could be done?
Currently, the checkout object doesn't have metafields if that's what you're trying to do. If anything, if you needed to store a pickup location somewhere, you may be able to do it on the order itself after it is placed since they do support metafields. You'd need to do that via the API though, as opposed to using a checkout URL.