I've looked in the forums, but not found something to help.   I want to add custom items to the cart when the user is checking out, based on the contents of the cart. I've got the code to create the draft order, because the extra items can be variable costs, but how do I get the user to checkout with this draft order, instead of the cart? not sure I'm making sense here.   I've seen apps like Hulk discount, and the Hulk custom product options do this, how's it done?   Dave ... View more

I'm having a problem with /admin/inventory_levels/set.json. I post the JSON but I always get back a status 400 {"errors":{"inventory_item_id":"Required parameter missing or invalid"}} the JSON I'm posting is this {"location_id":5803180126,"available":100,"inventory_item_id":12894264033374} I'm not sure how this is going wrong. Does anyone have an idea of what I should try? I can lookup the inventory_item_id successfully with /admin/inventory_levels.json?inventory_item_ids=12894264033374 Dave     ... View more