FastAPI Todo Application

A modern, fast, and feature-rich todo management API built with FastAPI, SQLAlchemy, and SQLite.

🚀 Quick Start

Prerequisites

• Python 3.8+
• pip package manager

Installation & Setup

1. Clone and navigate to the project:

   git clone <repository-url>
   cd todoapp
   

2. Create a virtual environment (recommended):

   python -m venv venv
   source venv/bin/activate  # On Windows: venv\Scripts\activate
   

3. Install dependencies:

   pip install -r requirements.txt
   

4. Initialize the database:

   alembic upgrade head
   

5. Start the server:

   uvicorn main:app --host 0.0.0.0 --port 8000
   

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

📋 Features

• ✅ Full CRUD Operations - Create, read, update, and delete todos
• 🔍 Pagination Support - Efficient handling of large todo lists
• 📊 SQLite Database - Lightweight, serverless database
• 🔄 Database Migrations - Version-controlled schema changes with Alembic
• 📚 Auto-generated Documentation - Interactive API docs with Swagger UI
• 🌐 CORS Enabled - Cross-origin requests supported
• 💪 Type Safety - Full Pydantic validation and type hints
• 🏥 Health Monitoring - Built-in health check endpoint
• 🎯 Production Ready - Structured codebase with best practices

🛠 Tech Stack

• FastAPI - Modern, fast web framework for building APIs
• SQLAlchemy - SQL toolkit and ORM
• Alembic - Database migration tool
• Pydantic - Data validation using Python type annotations
• SQLite - Lightweight, file-based database
• Uvicorn - Lightning-fast ASGI server

📡 API Reference

Base Endpoints

Method	Endpoint	Description
GET	/	API information and links
GET	/health	Health check status
GET	/docs	Interactive API documentation
GET	/redoc	Alternative API documentation
GET	/openapi.json	OpenAPI specification

Todo Management

Method	Endpoint	Description	Request Body
POST	/todos/	Create a new todo	TodoCreate
GET	/todos/	List all todos	Query params: skip, limit
GET	/todos/{todo_id}	Get specific todo	-
PUT	/todos/{todo_id}	Update todo	TodoUpdate
DELETE	/todos/{todo_id}	Delete todo	-

Request/Response Models

TodoCreate

{
  "title": "string",
  "description": "string (optional)",
  "completed": false
}

TodoUpdate

{
  "title": "string (optional)",
  "description": "string (optional)",
  "completed": "boolean (optional)"
}

TodoResponse

{
  "id": 1,
  "title": "string",
  "description": "string",
  "completed": false,
  "created_at": "2024-01-01T00:00:00Z",
  "updated_at": "2024-01-01T00:00:00Z"
}

🗂 Project Structure

todoapp/
├── main.py                 # FastAPI application entry point
├── requirements.txt        # Python dependencies
├── alembic.ini            # Alembic configuration
├── ruff.toml              # Code linting configuration
├── app/
│   ├── __init__.py
│   ├── db/
│   │   ├── __init__.py
│   │   ├── base.py        # SQLAlchemy Base class
│   │   └── session.py     # Database session configuration
│   ├── models/
│   │   ├── __init__.py
│   │   └── todo.py        # Todo SQLAlchemy model
│   └── schemas/
│       ├── __init__.py
│       └── todo.py        # Pydantic schemas
└── alembic/
    ├── env.py             # Alembic environment configuration
    ├── script.py.mako     # Migration script template
    └── versions/          # Database migration files
        └── 001_initial_todo_table.py

🧪 Development

Running in Development Mode

uvicorn main:app --reload --host 0.0.0.0 --port 8000

Code Quality

This project uses Ruff for linting and formatting:

ruff check .
ruff format .

Database Operations

Create a new migration:

alembic revision --autogenerate -m "Description of changes"

Apply migrations:

alembic upgrade head

Rollback migrations:

alembic downgrade -1

🔧 Configuration

Database

• Type: SQLite
• Location: /app/storage/db/db.sqlite
• Connection: Automatically created on startup

Environment Variables

No environment variables are required for basic operation. The application uses sensible defaults for development.

🏥 Health Check

The application includes a health check endpoint that returns the service status:

curl http://localhost:8000/health

Response:

{
  "status": "healthy",
  "service": "Todo API"
}

📖 API Documentation

Once the server is running, access the documentation at:

• Swagger UI: http://localhost:8000/docs
• ReDoc: http://localhost:8000/redoc
• OpenAPI JSON: http://localhost:8000/openapi.json

🚀 Deployment

For production deployment, consider:

1. Use a production WSGI server:

   pip install gunicorn
   gunicorn main:app -w 4 -k uvicorn.workers.UvicornWorker
   

2. Set up proper logging and monitoring

3. Configure environment-specific settings

4. Use a more robust database (PostgreSQL, MySQL)

5. Set up SSL/TLS certificates

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Run tests and linting
5. Submit a pull request

📝 License

This project is open source and available under the MIT License.