EventCatalog | Entities | CartItem

CartItem

Represents an individual item within a shopping cart.

Entity

Overview

The CartItem entity represents individual products within a customer’s shopping cart. It maintains snapshots of product information and pricing to ensure consistency during the shopping session.

Entity Properties

Name	Type	Required	Description
`cartItemId`	`UUID`	Required	Unique identifier for the cart item
`cartId`	`UUID`	Required	Shopping cart this item belongs to
`productId`	`UUID`	Required	Product being added to cart
`sku`	`string`	Required	Product SKU at time of adding to cart
`productName`	`string`	Required	Product name snapshot at time of adding to cart
`productImage`	`string`	Optional	Product image URL snapshot
`quantity`	`integer`	Required	Quantity of this product in the cart
`unitPrice`	`decimal`	Required	Unit price at time of adding to cart
`totalPrice`	`decimal`	Required	Total price for this line item (quantity × unit price)
`originalPrice`	`decimal`	Optional	Original product price before any discounts
`discountAmount`	`decimal`	Optional	Discount applied to this line item
`productVariant`	`object`	Optional	Product variant details (size, color, etc.)
`isAvailable`	`boolean`	Required	Whether the product is still available
`notes`	`string`	Optional	Customer notes for this item
`addedAt`	`DateTime`	Required	Date and time when item was added to cart
`updatedAt`	`DateTime`	Optional	Date and time when item was last updated

Relationships

ShoppingCart: Each cart item belongs to one ShoppingCart (identified by cartId).
Product: Each cart item references one Product (identified by productId).

Price Calculations

Total Price = Quantity × Unit Price - Discount Amount
Savings = Original Price - Unit Price (if applicable)

Examples

CartItem #1: iPhone 15 Pro, quantity 1, $999.99 unit price, no discount.
CartItem #2: Running Shoes Size 9, quantity 2, $64.99 unit price (was $129.99).
CartItem #3: T-Shirt Large/Blue, quantity 3, $19.99 unit price.

Business Rules

Quantity must be greater than zero
Unit price is captured at time of adding to maintain consistency
Product availability is checked when cart is accessed
Unavailable items are marked but not automatically removed
Total price is recalculated when quantity changes
Product snapshots prevent price changes from affecting active carts
Maximum quantity limits may apply per product type