# No as a Service (NaaS)

A lightweight, production-ready HTTP service that always says "no" in various formats.

## Features

- Minimal dependencies (pure Rust, standard library only)
- Multiple response formats (text, JSON, XML, YAML, boolean)
- Mobile-responsive web frontend
- CORS support
- Health check endpoint
- Optimized for small binary size (~1MB)
- Container-ready with health checks

## API Endpoints

- `GET /` - Minimalist web page displaying "No"
- `GET /playground` - Interactive API testing playground
- `GET /api/no` - Returns plain text "no"
- `GET /api/no?format=json` - Returns `{"answer": "no"}`
- `GET /api/no?format=bool` - Returns `false`
- `GET /api/no?format=xml` - Returns XML response
- `GET /api/no?format=yaml` - Returns YAML response
- `GET /health` - Health check endpoint

## Quick Start

### Local Development

```bash
# Build and run locally
cd naas
cargo build --release
PORT=8080 ./target/release/naas
```

Visit http://localhost:8080

### Container Deployment with Podman

```bash
# Build container
cd naas
BUILDAH_FORMAT=docker podman build -t naas:latest -f Containerfile .

# Run container
podman run -d \
  --name naas \
  -p 8080:8080 \
  --restart=always \
  naas:latest

# Check health
curl http://localhost:8080/health
```

### Systemd Service Deployment

1. **Setup user and directory:**
```bash
# Create service user
sudo useradd -r -s /bin/false naas

# Copy application files
sudo mkdir -p /opt/naas
sudo cp -r naas/* /opt/naas/
sudo chown -R naas:naas /opt/naas
```

2. **Install systemd service:**
```bash
# Copy service file
sudo cp naas/naas.service /etc/systemd/system/

# Reload systemd and start service
sudo systemctl daemon-reload
sudo systemctl enable naas
sudo systemctl start naas

# Check status
sudo systemctl status naas
```

3. **View logs:**
```bash
sudo journalctl -u naas -f
```

## Production Deployment to no.donothireus.com

### Caddy Reverse Proxy Configuration

```caddyfile
no.donothireus.com {
    reverse_proxy localhost:8080 {
        header_up Host {host}
        header_up X-Real-IP {remote_host}
        header_up X-Forwarded-For {remote_host}
        header_up X-Forwarded-Proto {scheme}
    }
}
```

### Full Production Setup

1. **Deploy application** using systemd service (see above)

2. **Configure Caddy** with the above Caddyfile configuration (SSL certificates are automatic with Caddy)

3. **Restart services:**
```bash
sudo systemctl restart caddy
sudo systemctl restart naas
```

## Performance

- Binary size: ~1MB (release build with optimizations)
- Memory usage: <10MB
- Startup time: <100ms
- Request latency: <1ms

## Development

### Building from Source

```bash
# Debug build
cargo build

# Release build with optimizations
cargo build --release

# Run tests
cargo test
```

### Container Build Options

```bash
# Multi-platform build (if needed)
podman build --platform linux/amd64,linux/arm64 -t naas:latest .

# Build with specific Rust version
podman build --build-arg RUST_VERSION=1.75 -t naas:latest .
```

## Security

- Runs as non-root user (UID 1000)
- Read-only container filesystem
- No new privileges
- All capabilities dropped except NET_BIND_SERVICE
- Memory and CPU limits enforced
- CORS headers properly configured

## License

MIT