Im working with an app that will provide shipping rates for Shopify shops, but i ran into a problem i hope you can help me with.
The problem is that, we define shipping rules on our platform regarding to the Shopify order data from the Carrier Service, but i need to know if a discount was added or some promocode, but i can't see that in the Carrier Service request. Below is an example of this request:
As you can see im not able to see that an discount was added in this checkout. I noticed i have to get the Checkout object to know this, but my question is "How do i know the Checkout ID/Token, so i can find the checkout?"