Working on a site that will have a store, and obviously the store will be managed by Shopify. We want to sell upgrades to users on our site, so we're looking for a way to connect purchases to our users.
I don't want to rely on users' email addresses in our system being the same as email addresses for purchases in Stripe, so I'm wondering what the best/reliable way is to make the connection. The landing_site attribute is somewhat useful, but if someone removes a custom param from that then we've lost our thread. It'd also be nice to have hidden products that are still purchasable with a given user-specific link - that way, we can be more convinced that landing_site is an accurate reference, and we can also have some control over showing that link in our site (or not, if they've already purchased certain things).
I guess another option that'd be cool is constructing an order with some internal metadata reference on our side (via the API), and then pass users through to Shopify to enter payment details and such. All purchases would be tracked via webhooks to make the connection after payment is made.
I've not used Shopify before (but am certainly at home with APIs and Ruby), so I'm not quite sure what the best way forward is with this, so suggestions are very much welcome :)