(backend-granian)=

# Granian

High-performance Rust-based server supporting both ASGI and WSGI.

**Use when:** Maximum performance, modern deployments
**Don't use when:** Need mature ecosystem (use {ref}`backend-gunicorn` or {ref}`backend-uvicorn-asgi`)

## Installation

```bash
pip install django-prodserver[granian]
```

## Backends

(backend-granian-asgi)=

### ASGI Mode

For async Django with WebSocket support:

```python
PRODUCTION_PROCESSES = {
    "web": {
        "BACKEND": "django_prodserver.backends.servers.granian.GranianASGIServer",
        "ARGS": {
            "address": "0.0.0.0",
            "port": "8000",
            "workers": "4",
        }
    }
}
```

(backend-granian-wsgi)=

### WSGI Mode

For traditional Django:

```python
PRODUCTION_PROCESSES = {
    "web": {
        "BACKEND": "django_prodserver.backends.servers.granian.GranianWSGIServer",
        "ARGS": {
            "address": "0.0.0.0",
            "port": "8000",
            "workers": "4",
        }
    }
}
```

## Common ARGS

| Argument           | Default     | Description                     |
| ------------------ | ----------- | ------------------------------- |
| `address`          | `127.0.0.1` | Address to bind                 |
| `port`             | `8000`      | Port to bind                    |
| `workers`          | `1`         | Worker processes                |
| `threads`          | `1`         | Threads per worker (WSGI)       |
| `blocking-threads` | `1`         | Blocking threads (ASGI)         |
| `backlog`          | `1024`      | Connection backlog              |
| `http`             | `auto`      | HTTP version (`auto`, `1`, `2`) |
| `log-level`        | `info`      | Log level                       |
| `log-access`       | `True`      | Enable access logging           |
| `ssl-cert`         | `None`      | SSL certificate path            |
| `ssl-key`          | `None`      | SSL key path                    |

## Examples

### High-Performance ASGI

```python
"ARGS": {
    "address": "0.0.0.0",
    "port": "8000",
    "workers": "4",
    "blocking-threads": "2",
    "log-access": "False",
}
```

### WSGI with Thread Pool

```python
"ARGS": {
    "address": "0.0.0.0",
    "port": "8000",
    "workers": "2",
    "threads": "4",
}
```

### HTTP/2

```python
"ARGS": {
    "http": "2",
    "workers": "4",
}
```

## ASGI vs WSGI

| Feature      | ASGI             | WSGI        |
| ------------ | ---------------- | ----------- |
| Async views  | Yes              | No          |
| WebSockets   | Yes              | No          |
| Thread model | Async + blocking | Thread pool |

## Troubleshooting

**Installation fails:** Granian requires Rust on some platforms. Try `pip install --upgrade granian`

**ASGI app not found:** Ensure `asgi.py` exists

## Links

- [Granian GitHub](https://github.com/emmett-framework/granian)