Shopping List API

A simple internal API to track shopping list items using SQLite and FastAPI.

Setup

# Install dependencies
pip install -r requirements.txt

# Run the server
uvicorn main:app --reload

The API will be available at http://localhost:8000.

Database

SQLite database file: shopping.db (created automatically on first startup).

Schema:

• products (id, name, sku?, created_at)
• lists (id, name, created_at)
• list_items (id, list_id, product_id, quantity, added_at; foreign keys with cascade)

API Reference

Root

GET /
Returns a welcome message.

Response:

{ "message": "Shopping List API" }

Products

POST /products
Create a product.

Body:

{ "name": "string", "sku": "optional string" }

GET /products
List all products.

GET /products/{id}
Get a product by ID.

DELETE /products/{id}
Delete a product.

Lists

POST /lists
Create a shopping list.

Body:

{ "name": "string" }

GET /lists
List all lists.

GET /lists/{id}
Get a list with its items (includes product details in items).

DELETE /lists/{id}
Delete a list (cascades to items).

List Items

POST /lists/{list_id}/items
Add a product to a list.

Body:

{ "product_id": 1, "quantity": 2 }

PATCH /lists/{list_id}/items/{item_id}
Update the quantity of an item in a list.

Body:

{ "quantity": 5 }

DELETE /lists/{list_id}/items/{item_id}
Remove an item from a list.

GET /lists/{list_id}/items
List items in a list (includes product name and sku).

Manual Testing

You can use curl or any HTTP client.

Example flow:

# Create products
curl -X POST http://localhost:8000/products -H "Content-Type: application/json" -d '{"name":"Paper Plates","sku":"PP-001"}'
curl -X POST http://localhost:8000/products -H "Content-Type: application/json" -d '{"name":"Bread"}'

# Create a list
curl -X POST http://localhost:8000/lists -H "Content-Type: application/json" -d '{"name":"Picnic List"}'

# Add items to the list (use IDs from previous responses)
curl -X POST http://localhost:8000/lists/1/items -H "Content-Type: application/json" -d '{"product_id":1,"quantity":2}'
curl -X POST http://localhost:8000/lists/1/items -H "Content-Type: application/json" -d '{"product_id":2,"quantity":1}'

# Get list with items
curl http://localhost:8000/lists/1

# Update quantity
curl -X PATCH http://localhost:8000/lists/1/items/1 -H "Content-Type: application/json" -d '{"quantity":5}'

# List items in list
curl http://localhost:8000/lists/1/items

# Delete item
curl -X DELETE http://localhost:8000/lists/1/items/2

# Delete list (cascades)
curl -X DELETE http://localhost:8000/lists/1

Running Tests

pytest test_main.py

Tests cover:

• Root endpoint
• Product CRUD
• List CRUD
• List items management (add, update, delete, cascade)

Notes

• This is an internal API; security/auth not implemented.
• For production use, add proper error handling, validation, and possibly a connection pool.