todoapp-us6a2a/README.md

# FastAPI Todo App

A simple Todo API built with FastAPI and SQLite.

## Features

- 📝 **Todo Management**: Create, read, update, and delete todo items
- 🔍 **Filtering & Pagination**: Filter todos by completion status and paginate results
- 📊 **Health Monitoring**: Endpoint to check application and database health
- 🔧 **Environment Variables**: Access to environment variables via API
- 🛡️ **Error Handling**: Comprehensive error handling with meaningful messages
- 📚 **API Documentation**: Auto-generated Swagger/OpenAPI documentation

## Tech Stack

- **FastAPI**: Modern, fast (high-performance) web framework for building APIs
- **SQLAlchemy**: SQL toolkit and Object-Relational Mapping (ORM)
- **Alembic**: Database migration tool
- **SQLite**: Lightweight, file-based database
- **Pydantic**: Data validation and settings management
- **Uvicorn**: ASGI server for running the application

## Project Structure

```
├── app/
│   ├── api/
│   │   └── v1/
│   │       ├── env_vars.py        # Environment variables endpoints
│   │       ├── health.py          # Health check endpoint
│   │       ├── router.py          # API router
│   │       └── todos.py           # Todo CRUD endpoints
│   ├── core/
│   │   ├── config.py              # Application configuration
│   │   └── exceptions.py          # Custom exception handlers
│   ├── database/
│   │   └── session.py             # Database session setup
│   ├── models/
│   │   └── todo.py                # SQLAlchemy models
│   └── schemas/
│       └── todo.py                # Pydantic schemas
├── migrations/                    # Alembic migration files
├── alembic.ini                    # Alembic configuration
├── main.py                        # Application entry point
└── requirements.txt               # Project dependencies
```

## Setup Instructions

### Prerequisites

- Python 3.8+
- pip (Python package installer)

### Installation

1. Clone the repository:
   ```bash
   git clone <repository-url>
   cd todoapp-us6a2a
   ```

2. Install dependencies:
   ```bash
   pip install -r requirements.txt
   ```

3. Create the database and run migrations:
   ```bash
   alembic upgrade head
   ```

### Running the Application

Start the application with:

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

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

## API Documentation

Interactive API documentation is available at:

- Swagger UI: http://localhost:8000/docs
- ReDoc: http://localhost:8000/redoc

## API Endpoints

### Health Check

- `GET /health` - Check application health

### Todo Endpoints

- `GET /api/v1/todos` - List all todos (with optional filtering and pagination)
- `POST /api/v1/todos` - Create a new todo
- `GET /api/v1/todos/{todo_id}` - Get a specific todo
- `PATCH /api/v1/todos/{todo_id}` - Update a todo
- `DELETE /api/v1/todos/{todo_id}` - Delete a todo

### Environment Variables Endpoints

- `GET /api/v1/env/content` - Get the value of the CONTENT environment variable

## Example Usage

### Create a Todo

```bash
curl -X 'POST' \
  'http://localhost:8000/api/v1/todos/' \
  -H 'Content-Type: application/json' \
  -d '{
  "title": "Learn FastAPI",
  "description": "Build a sample todo app",
  "completed": false
}'
```

### List All Todos

```bash
curl -X 'GET' 'http://localhost:8000/api/v1/todos/'
```

### Get a Specific Todo

```bash
curl -X 'GET' 'http://localhost:8000/api/v1/todos/1'
```

### Update a Todo

```bash
curl -X 'PATCH' \
  'http://localhost:8000/api/v1/todos/1' \
  -H 'Content-Type: application/json' \
  -d '{
  "completed": true
}'
```

### Delete a Todo

```bash
curl -X 'DELETE' 'http://localhost:8000/api/v1/todos/1'
```

### Get CONTENT Environment Variable

```bash
curl -X 'GET' 'http://localhost:8000/api/v1/env/content'
```

To set the environment variable before running the application:

```bash
export CONTENT="Your content here"
uvicorn main:app --host 0.0.0.0 --port 8000 --reload
```

## License

This project is licensed under the MIT License.