Responder§

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

1. Install Unit with a Python 3.6+ language module.

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

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

3. Let’s try a Unit-friendly version of a tutorial app, saving it as /path/to/app/asgi.py:

   import responder
   
   app = responder.API()
   
   @app.route("/")
   def hello_world(req, resp):
       resp.text = "Hello, World!"
   
   @app.route("/hello/{who}")
   def hello_to(req, resp, *, who):
       resp.text = f"Hello, {who}!"
   

   The app.run() call is omitted because app will be directly run by Unit as an ASGI callable.

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 Responder configuration for Unit (use real values for type, home, and path):

   {
       "listeners": {
           "*:80": {
               "pass": "applications/responder"
           }
       },
   
       "applications": {
           "responder": {
               "type": "python 3.Y",
               "path": "/path/to/app/",
               "home": "/path/to/app/venv/",
               "working_directory": "/path/to/app/",
               "module": "asgi",
               "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
   
         Hello, World!
   
   $ curl http://localhost/hello/JohnDoe
   
         Hello, JohnDoe!