🚀 FastAPI Todo Backend

A modern, high-performance Todo API built with FastAPI, PostgreSQL, and Docker. This backend provides a robust REST API for managing todo items with full CRUD operations, data validation, and comprehensive error handling.

✨ Features

Core Functionality

• Full CRUD Operations: Create, read, update, and delete todos
• Data Validation: Pydantic models for request/response validation
• Error Handling: Comprehensive HTTP error responses
• Health Monitoring: Built-in health check endpoint

Technical Features

• PostgreSQL Integration: Robust database with SQLAlchemy ORM
• CORS Support: Cross-origin requests enabled for frontend integration
• Docker Containerization: Easy deployment and development setup
• Auto-generated Documentation: Interactive API docs with Swagger UI
• Database Migrations: Automatic table creation on startup
• Connection Pooling: Optimized database connections

🛠️ Tech Stack

• Framework: FastAPI 0.104+
• Database: PostgreSQL 13
• ORM: SQLAlchemy with declarative models
• Validation: Pydantic v2
• Server: Uvicorn ASGI server
• Containerization: Docker & Docker Compose
• Environment: Python 3.9+

🚀 Quick Start

Prerequisites

• Docker & Docker Compose
• Python 3.9+ (for local development)

Docker Setup (Recommended)

# Clone and navigate to backend directory
cd backend

# Start services
docker-compose up --build -d

# View logs
docker-compose logs -f app

Local Development Setup

# Install dependencies
pip install -r requirements.txt

# Set up environment
cp env.example .env
# Edit .env with your database credentials

# Run database migrations
python -c "from app.database import create_tables; create_tables()"

# Start development server
uvicorn app.main:app --reload --host 0.0.0.0 --port 8000

📚 API Documentation

Interactive Documentation

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

Core Endpoints

Method	Endpoint	Description	Request Body
GET	/	API welcome message	-
GET	/todos/	Get all todos	-
POST	/todos/	Create new todo	{"title": "string"}
GET	/todos/{id}	Get specific todo	-
PATCH	/todos/{id}	Update todo	{"title": "string", "completed": boolean}
DELETE	/todos/{id}	Delete todo	-
GET	/health	Health check	-

Response Models

{
  "id": 1,
  "title": "Complete project",
  "completed": false
}

🗄️ Database Schema

Todo Model

CREATE TABLE todos (
    id SERIAL PRIMARY KEY,
    title VARCHAR(200) NOT NULL,
    completed BOOLEAN DEFAULT FALSE,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

🔧 Configuration

Environment Variables

# Database Configuration
POSTGRES_USER=user
POSTGRES_PASSWORD=shan
POSTGRES_DB=todo_list
DB_HOST=db
DB_PORT=5432

# Optional
DATABASE_URL=postgresql://user:shan@db:5432/todo_list
DB_ECHO=false  # Set to true for SQL query logging

Docker Services

• app: FastAPI application (Port 8000)
• db: PostgreSQL database (Port 5432)

🧪 Testing

# Test API endpoints
curl http://localhost:8000/health
curl http://localhost:8000/todos/
curl -X POST -H "Content-Type: application/json" -d '{"title":"Test todo"}' http://localhost:8000/todos/

📁 Project Structure

backend/
├── app/
│   ├── __init__.py
│   ├── main.py          # FastAPI application and routes
│   ├── models.py        # SQLAlchemy database models
│   └── database.py      # Database configuration and connection
├── requirements.txt     # Python dependencies
├── Dockerfile          # Container configuration
├── docker-compose.yml  # Multi-service orchestration
├── .env               # Environment variables
└── README.md          # This file

🚀 Deployment

Production Considerations

• Use environment-specific database credentials
• Enable SSL/TLS for database connections
• Configure proper logging levels
• Set up database backups
• Use a reverse proxy (nginx) for production
• Implement rate limiting and authentication

Docker Production

# Build production image
docker build -t todo-api:latest .

# Run with production settings
docker run -d -p 8000:8000 --env-file .env todo-api:latest

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests if applicable
5. Submit a pull request

📄 License

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