# Todo Application API

A Todo application backend built with Python, FastAPI, and SQLAlchemy.

## Features

- Create, read, update, and delete todo items
- List all todos with pagination
- Persistent storage using SQLite
- API documentation with Swagger UI and ReDoc

## Tech Stack

- **FastAPI**: High-performance web framework for building APIs
- **SQLAlchemy**: SQL toolkit and ORM
- **Alembic**: Database migration tool
- **Pydantic**: Data validation and settings management
- **SQLite**: Lightweight disk-based database (stored in `/storage/db/db.sqlite`)
- **Uvicorn**: ASGI server

## Project Structure

```
.
├── alembic/                  # Database migrations
│   └── versions/             # Migration scripts
├── app/                      # Application code
│   ├── api/                  # API endpoints
│   │   └── endpoints/        # API route handlers
│   ├── core/                 # Core functionality
│   ├── db/                   # Database
│   │   └── repositories/     # Database repositories
│   ├── models/               # SQLAlchemy models
│   └── schemas/              # Pydantic schemas
├── alembic.ini               # Alembic config
├── main.py                   # Application entry point
└── requirements.txt          # Dependencies
```

## Getting Started

### Prerequisites

- Python 3.8+

### Installation

1. Clone the repository
2. Install the dependencies:
   ```
   pip install -r requirements.txt
   ```

3. Run database migrations:
   ```
   alembic upgrade head
   ```
   This will create the SQLite database file at `/storage/db/db.sqlite`

4. Start the server:
   ```
   uvicorn main:app --reload
   ```

### Database Configuration

The application uses SQLite as its database backend. The database file is stored at `/storage/db/db.sqlite`, outside the project root directory for better data isolation. The directory is automatically created if it doesn't exist.

To change the database location, modify the `DB_DIR` variable in `app/core/config.py`.

### API Documentation

Once the server is running, you can access:

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

## API Endpoints

- `GET /api/v1/todos`: List all todos
- `POST /api/v1/todos`: Create a new todo
- `GET /api/v1/todos/{todo_id}`: Get a specific todo
- `PUT /api/v1/todos/{todo_id}`: Update a specific todo
- `DELETE /api/v1/todos/{todo_id}`: Delete a specific todo