Cart Concepts
In this document, you’ll get an overview of the main concepts of a cart.
Shipping and Billing Addresses
A cart has a shipping and billing address. Both of these addresses are represented by the Address data model.
Line Items
A line item, represented by the LineItem data model, is a product added to the cart. A cart has multiple line items.
A line item stores some of the product’s attributes, such as the product_title and product_description. It also stores data related to the item’s quantity and price.
A product can be from the Product Module but can also be a custom item used only in this cart.
Shipping Methods
A shipping method, represented by the ShippingMethod data model, is the method used to fulfill the items in the cart after the order is placed. A cart can have more than one shipping method.
If the shipping method is created from a shipping option, typically available through the Fulfillment Module, its ID is stored in the shipping_option_id.
A shipping method can also be a custom method associated with this cart only.
data Attribute
When fulfilling the order after its placed, you may use a third-party fulfillment provider that requires additional custom data to be passed along from the checkout process.
The ShippingMethod data model has a data attribute. It's an object used to store custom data relevant later for fulfillment.
In the Medusa application, it's the data is passed to the Fulfillment Module when fulfilling items.