Django Deployment Guide
===

Tools
----
* Gunicorn: Worker process management
* Systemd: Service management and monitoring
* Nginx: Reverse proxy server
* Certbot: SSL/TLS certificate deployment

Steps
----

1. Preparing basic enviroment, including:
* Git / Subversion
* Pyenv & Pipenv
* MariaDB / PostgreSQL
* Service User for running Gunicorn

2. Download the application repo

3. Add deployment settings to the application

4. Create the static file folder and copy static files to it

    $ mkdir -p STATIC_ROOT
    $ pipenv run ./manage.py collectstatic

Replace STATIC_ROOT with the one in settings

5. Install Gunicorn and Gevent (Better to add these in Pipfile before deployment)

6. Add Systemd configurations

* /etc/systemd/system/gunicorn.service

        [Unit]
        Description=gunicorn daemon
        Requires=gunicorn.socket
        After=network.target

        [Service]
        PIDFile=/run/gunicorn/pid
        User=SERVICE_USER
        Group=SERVICE_GROUP
        RuntimeDirectory=gunicorn
        WorkingDirectory=PROJECT_PATH
        Environment=PYTHONUNBUFFERED=True
        ExecStart=GUNICORN_EXECUTABLE \
                  --pid /run/gunicorn/pid \
                  --bind unix:/run/gunicorn.socket \
                  --worker-class gevent \
                  APP_NAME.wsgi
        ExecReload=/bin/kill -s HUP $MAINPID
        ExecStop=/bin/kill -s TERM $MAINPID
        PrivateTmp=true

        [Install]
        WantedBy=multi-user.target

* /etc/systemd/system/gunicorn.socket

        [Unit]
        Description=gunicorn socket

        [Socket]
        ListenStream=/run/gunicorn.socket

        [Install]
        WantedBy=sockets.target

* /etc/tmpfiles.d/gunicorn.conf

        d /run/gunicorn 0755 SERVICE_USER SERVICE_GROUP -

Replace these variables to fit your situation:
* APP_NAME
* PROJECT_PATH
* SERVICE_USER
* SERVICE_GROUP
* GUNICORN_EXECUTABLE

7. Start gunicorn service and enable autostart

    $ sudo systemctl start gunicorn.socket
    $ sudo systemctl enable gunicorn.socket

8. Install Nginx server

9. Modify Nginx configuration

/etc/nginx/nginx.conf

    http {
        server {
            server_name APP_DOMAIN;
            location / {
                proxy_pass http://unix:/run/gunicorn.socket;
                proxy_set_header Host $host;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header X-Forwarded-Proto $http_x_forwarded_proto;
            }
            location /static/ {
                alias STATIC_ROOT;
            }
        }
    }

Replace these variables to fit your situation:
* APP_DOMAIN
* STATIC_ROOT

10. Start nginx service and enable autostart

    $ sudo systemctl start nginx.service
    $ sudo systemctl enable nginx.service

11. Install Certbot with nginx plugin

12. Get and serve a certificate for the application

    $ sudo certbot --nginx

13. Enable certbot autorenew for the certificates