NGINX Unit
v. 1.25.0

Pyramid§

To run apps built with the Pyramid web framework using Unit:

  1. Install Unit with a Python 3 language module.

  2. Create a virtual environment to install Pyramid’s PIP package:

    $ cd /path/to/app/
    $ python3 --version
          Python 3.Y.Z
    $ python3 -m venv venv
    $ source venv/bin/activate
    $ pip install pyramid
    $ deactivate
    

    Warning

    Create your virtual environment with a Python version that matches the language module from Step 1 up to the minor number (3.Y in this example). Also, the app type in Step 5 must resolve to a similarly matching version; Unit doesn’t infer it from the environment.

    Note

    Here, $VENV isn’t set because Unit picks up the virtual environment from home in Step 5.

  3. Let’s see how the apps from the Pyramid tutorial run on Unit.

    We modify the tutorial app, saving it as /path/to/app/wsgi.py:

    from pyramid.config import Configurator
    from pyramid.response import Response
    
    def hello_world(request):
        return Response('<body><h1>Hello, World!</h1></body>')
    
    with Configurator() as config:
        config.add_route('hello', '/')
        config.add_view(hello_world, route_name='hello')
        app = config.make_wsgi_app()
    # serve(app, host='0.0.0.0', port=6543)
    

    Note that we’ve dropped the server code; also, mind that Unit imports the module, so the if __name__ == '__main__' idiom would be irrelevant.

    To load the configuration, we place a wsgi.py file next to development.ini in /path/to/app/:

    from pyramid.paster import get_app, setup_logging
    
    app = get_app('development.ini')
    setup_logging('development.ini')
    

    This sets up the WSGI application for Unit; if the .ini’s pathname is relative, provide the appropriate working_directory in Unit configuration.

  4. Run the following command so Unit can access the application directory:

    # chown -R unit:unit /path/to/app/
    

    Note

    The unit:unit user-group pair is available only with official packages, Docker images, and some third-party repos. Otherwise, account names may differ; run the ps aux | grep unitd command to be sure.

    For further details, including permissions, see the security checklist.

  5. Next, prepare the Pyramid configuration for Unit (use real values for type, home, and path):

    {
        "listeners": {
            "*:80": {
                "pass": "applications/pyramid"
            }
        },
    
        "applications": {
            "pyramid": {
                "type": "python 3.Y",
                "working_directory": "/path/to/app/",
                "path": "/path/to/app/",
                "home": "/path/to/app/venv/",
                "module": "wsgi",
                "callable": "app"
            }
        }
    }
    
  6. Upload the updated configuration. Assuming the JSON above was added to config.json:

    # curl -X PUT --data-binary @config.json --unix-socket \
           /path/to/control.unit.sock http://localhost/config/
    

    Note

    The control socket path may vary; run unitd -h or see Startup and Shutdown for details.

    After a successful update, your app should be available on the listener’s IP address and port:

    $ curl http://localhost
    
          <body><h1>Hello, World!</h1></body>