# Number Divisibility API

A simple REST API built with FastAPI that checks if a number is divisible by 2 and by 3.

## Features

- Check if a number is divisible by 2 and by 3 via GET or POST requests
- Dedicated endpoints for divisibility by 2 and by 3
- History endpoint to view all past checks
- Database integration with SQLAlchemy and SQLite
- Database migrations managed by Alembic
- Health endpoint for monitoring
- OpenAPI documentation built-in

## API Endpoints

### GET /

Welcome message for the API.

### GET /divisibility/{number}

Check if a number is divisible by 2 and by 3 using a path parameter.

**Parameters:**
- `number` (integer): The number to check

**Response:**
```json
{
  "number": 42,
  "is_divisible_by_2": true,
  "is_divisible_by_3": false
}
```

### POST /divisibility

Check if a number is divisible by 2 and by 3 using a JSON request body.

**Request Body:**
```json
{
  "number": 42
}
```

**Response:**
```json
{
  "number": 42,
  "is_divisible_by_2": true,
  "is_divisible_by_3": false
}
```

### GET /divisibility/by3/{number}

Check if a number is divisible by 3 using a path parameter.

**Parameters:**
- `number` (integer): The number to check

**Response:**
```json
{
  "number": 9,
  "is_divisible_by_2": false,
  "is_divisible_by_3": true
}
```

### POST /divisibility/by3

Check if a number is divisible by 3 using a JSON request body.

**Request Body:**
```json
{
  "number": 9
}
```

**Response:**
```json
{
  "number": 9,
  "is_divisible_by_2": false,
  "is_divisible_by_3": true
}
```

### GET /history

Get the history of all divisibility checks performed.

**Response:**
```json
[
  {
    "number": 42,
    "is_divisible_by_2": true,
    "is_divisible_by_3": false,
    "id": 1,
    "created_at": "2025-05-14T12:34:56.789Z"
  },
  {
    "number": 7,
    "is_divisible_by_2": false,
    "is_divisible_by_3": false,
    "id": 2,
    "created_at": "2025-05-14T12:35:01.234Z"
  },
  {
    "number": 9,
    "is_divisible_by_2": false,
    "is_divisible_by_3": true,
    "id": 3,
    "created_at": "2025-05-14T12:36:05.678Z"
  }
]
```

### GET /health

Health check endpoint to verify the API is running.

**Response:**
```json
{
  "status": "healthy",
  "api_version": "1.0.0",
  "service": "Number Divisibility API"
}
```

## Installation

1. Clone the repository
2. Install dependencies:
   ```
   pip install -r requirements.txt
   ```
3. Run database migrations:
   ```
   alembic upgrade head
   ```

## Running the API

```
uvicorn main:app --reload
```

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

## API Documentation

FastAPI automatically generates interactive API documentation:

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