CartSerializer Documentation

This section outlines the serializer used in the Cart API. The CartSerializer is responsible for transforming the data between complex types (e.g., Django models) and Python data types (e.g., JSON), allowing the creation, update, and retrieval of shopping cart information.

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Serializers

1. Cart Serializer: CartSerializer

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1. Cart Serializer

Serializer Overview

CartSerializer is used to serialize shopping cart data. A shopping cart contains multiple cart items, user information, and calculates important fields such as subtotal, total discount, final total, and the total number of items in the cart.

Fields

Field	Type	Description
id	integer	The unique identifier for the cart.
user_id	integer	The ID of the user associated with the cart.
items	array	A list of cart items serialized using CartItemSerializer.
subtotal	decimal	The subtotal of the cart before discounts.
total_discount	decimal	The total discount applied to the cart.
final_total	decimal	The final total after applying the discount.
total_items	integer	The total number of items in the cart.
created_at	datetime	The timestamp when the cart was created.
updated_at	datetime	The timestamp when the cart was last updated.

Example Response

Response

{
  "id": 1,
  "user_id": 123,
  "items": [
    {
      "id": 1,
      "product": {
        "id": 101,
        "name": "Product Name",
        "price": 50.00,
        "discount_percent": 10,
        "description": "A detailed description of the product.",
        "images": [
          {
            "id": 1,
            "image": "http://example.com/media/products/product1_image.jpg"
          }
        ],
        "primary_image": "http://example.com/media/products/product1_image.jpg"
      },
      "variant": {
        "id": 201,
        "variant_price": 45.00,
        "discounted_price": 40.50,
        "stock_quantity": 10,
        "is_available": true,
        "is_active": true,
        "size": {
          "id": 301,
          "size": "L",
          "value": "Large"
        }
      },
      "quantity": 2,
      "total_price": 90.00,
      "discount_amount": 9.00,
      "final_price": 81.00,
      "is_direct_purchase": false,
      "has_purchased": false,
      "created_at": "2024-12-06T14:30:00Z",
      "updated_at": "2024-12-06T14:30:00Z"
    }
  ],
  "subtotal": 90.00,
  "total_discount": 9.00,
  "final_total": 81.00,
  "total_items": 1,
  "created_at": "2024-12-06T14:30:00Z",
  "updated_at": "2024-12-06T14:30:00Z"
}

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Serializer Methods

• CartSerializer.get_total_items(self, obj)

This method returns the total number of items in the cart by counting the related cart_items.

• CartSerializer.get_subtotal(self, obj)

This method calculates the subtotal of the cart by summing the total_price of each cart_item.

• CartSerializer.get_total_discount(self, obj)

This method calculates the total discount applied across all cart items by summing the discount_amount of each cart_item.

• CartSerializer.get_final_total(self, obj)

This method calculates the final total by subtracting the total discount from the subtotal, ensuring the result is never negative. It returns the final value rounded to two decimal places.

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