The discount_allocation object
discount_allocation object contains all of the information about how a particular discount affects a line item and how the price reduces. The object can be accessed on customer order and notification templates. Shopify Plus merchants can also access properties of the
discount_allocation object in the checkout.liquid layout file.
discount_allocation object has the following attributes:
The discounted amount on a line item by a particular discount. This amount is in the customer's local (presentment) currency.
The discount application that allocates the amount on the line item.