When Shopify cart is first created? Is it when new user first enters the site on Shopify or when first item is put into cart? When can I first access cart by ID in API calls to change numer of products in?
I'm going to have private Shopify application which will handle and store user files uploaded. User will pay for processing files. In fact one product for shop, user will have one product in cart, but count will change depending on how much files he wants to process. I need to associate uploaded files with user, respective cart, cause user data first entered when checking out the cart. Cart ID seems to be OK for me for that case.
