The first thing to do is to set all the relevant environment variables. Luckily, flask has an easy way of setting those: the .flaskenv file. Copy the .flaskenv-example file to .flaskenv and change the parameters accordingly. Be sure to set

    FLASK_ENV=production

in a production environment.

After the environment is set, the app can be run.

In stead of just typing python when one needs to spawn a python shell to test things out, it is recommended to type

    flask shell

this way, all useful variables are already imported.

Make a flask environment file .flaskenv with all the environment variables of your project. Set FLASK_ENV=development and run the app with

    flask run

Run flask with Gunicorn and Nginx. An example Gunicorn service file can be found here. This file should be saved as

    /etc/systemd/system/spikeball.service

and can be enabled and started as follows:

    sudo systemctl enable spikeball
    sudo systemctl start spikeball

An example Nginx proxy file can be found here and should be saved as

    /etc/nginx/sites-available/spikeball

to enable the website, this file should be statically linked to /etc/nginx/sites-enabled. do not forget to test and restart the Nginx service:

    sudo nginx -t
    sudo systemctl restart nginx

The example nginx file already assumes you installed and enabled certbot.