Notes of Set Up Django with Postgres, Nginx, and Gunicorn

Install the Packages

$ sudo apt update
$ sudo apt install python3-pip python3-dev libpq-dev postgresql postgresql-contrib nginx curl

Creating the PostgreSQL Database and User

$ sudo -u postgres psql
postgres=# CREATE DATABASE myproject;
postgres=# CREATE USER myprojectuser WITH PASSWORD 'password';
postgres=# ALTER ROLE myprojectuser SET client_encoding TO 'utf8';
postgres=# ALTER ROLE myprojectuser SET default_transaction_isolation TO 'read committed';
postgres=# ALTER ROLE myprojectuser SET timezone TO 'UTC';
postgres=# GRANT ALL PRIVILEGES ON DATABASE myproject TO myprojectuser;
postgres=# \q
$ sudo systemctl status postgresql
$ sudo systemctl start postgresql
$ sudo systemctl enable postgresql

Creating a Python Virtual Environment for your Project

$ sudo -H pip3 install --upgrade pip
$ sudo -H pip3 install virtualenv
$ mkdir ~/myprojectdir
$ cd ~/myprojectdir
$ virtualenv myprojectenv
$ source myprojectenv/bin/activate
# Note: When the virtual environment is activated (when your prompt has (myprojectenv) preceding it), use pip instead of pip3, even if you are using Python 3. The virtual environment’s copy of the tool is always named pip, regardless of the Python version.
(myprojectenv) $ pip install django gunicorn psycopg2-binary

Creating and Configuring a New Django Project

(myprojectenv) $ django-admin.py startproject myproject ~/myprojectdir
(myprojectenv) $ nano ~/myprojectdir/myproject/settings.py
. . .
# ~/myprojectdir/myproject/settings.py
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'myproject',
        'USER': 'myprojectuser',
        'PASSWORD': 'password',
        'HOST': 'localhost',
        'PORT': '',
    }
}
. . .
STATIC_URL = '/static/'
STATIC_ROOT = os.path.join(BASE_DIR, 'static/')
. . .
(myprojectenv) $ ~/myprojectdir/manage.py makemigrations
(myprojectenv) $ ~/myprojectdir/manage.py migrate
(myprojectenv) $ ~/myprojectdir/manage.py createsuperuser
(myprojectenv) $ sudo ufw allow 8000
(myprojectenv) $ ~/myprojectdir/manage.py runserver 0.0.0.0:8000
(myprojectenv) $ cd ~/myprojectdir
(myprojectenv) $ gunicorn --bind 0.0.0.0:8000 myproject.wsgi
(myprojectenv) $ deactivate

Creating systemd Socket and Service Files for Gunicorn

Option 1

$ sudo nano /etc/systemd/system/gunicorn.socket
. . .
[Unit]
Description=gunicorn socket

[Socket]
ListenStream=/run/gunicorn.sock

[Install]
WantedBy=sockets.target
. . .
$ sudo nano /etc/systemd/system/gunicorn.service
. . .
[Unit]
Description=gunicorn daemon
Requires=gunicorn.socket
After=network.target

[Service]
User=sammy
Group=www-data
WorkingDirectory=/home/sammy/myprojectdir
ExecStart=/home/sammy/myprojectdir/myprojectenv/bin/gunicorn \
          --access-logfile - \
          --workers 3 \
          --bind unix:/run/gunicorn.sock \
          myproject.wsgi:application

[Install]
WantedBy=multi-user.target
. . .
$ sudo systemctl start gunicorn.socket
$ sudo systemctl enable gunicorn.socket

Checking for the Gunicorn Socket File

$ sudo systemctl status gunicorn.socket
$ file /run/gunicorn.sock
$ sudo journalctl -u gunicorn.socket

Testing Socket Activation

$ sudo systemctl status gunicorn
$ sudo journalctl -u gunicorn
$ sudo systemctl daemon-reload
$ sudo systemctl restart gunicorn

Configure Nginx to Proxy Pass to Gunicorn

$ sudo nano /etc/nginx/sites-available/myproject

    server {
        listen 80;
        server_name server_domain_or_IP;

        location = /favicon.ico { access_log off; log_not_found off; }
        location /static/ {
            root /home/sammy/myprojectdir;
        }

        location / {
            include proxy_params;
            proxy_pass http://unix:/run/gunicorn.sock;
        }
    }
    
$ sudo ln -s /etc/nginx/sites-available/myproject /etc/nginx/sites-enabled
$ sudo nginx -t
$ sudo systemctl restart nginx

Creating systemd Socket and Service Files for Gunicorn

Option 2

Configure Gunicorn

The Gunicorn configuration is fairly simple, but it’s still important to get done. Create a gunicorn directory in your site’s root. You essentially need to tell it where to run its socket, how many workers to spawn, and where to log. Create a Python file called gunicorn-config.py, and make it look something like the one below.

import multiprocessing

bind = 'unix:/tmp/gunicorn.sock'
workers = multiprocessing.cpu_count() * 2 + 1
reload = True
daemon = True
accesslog = './access.log'
errorlog = './error.log'

$ gunicorn -c gunicorn/gunicorn-config.py your-project.wsgi

Configure Nginx

upstream your-gunicorn {
    server unix:/tmp/gunicorn.sock fail_timeout=0;
}

server {
    listen 80;
    listen [::]:80;
    client_max_body_size 4G;
    keepalive_timeout 70;

    server_name project-index.local;
    access_log /var/www/html/share/vt-env/myprojectDir/logs/access.log;
    error_log /var/www/html/share/vt-env/myprojectDir/logs/error.log info;

    root /var/www/html/share/vt-env/myprojectDir;

    location /static/ {
        autoindex on;
        expires 1M;
        access_log off;
        add_header Cache-Control "public";
        proxy_ignore_headers "Set-Cookie";
        alias /var/www/html/share/vt-env/myprojectDir/static;
    }

    location @proxy_to_app {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;
        proxy_pass   http://your-gunicorn;
    }

    location ~ \.php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_pass unix:/run/php/php7.4-fpm.sock;
    }

    location / {
        try_files $uri @proxy_to_app;
    }

    location ~ /\.ht {
        deny all;
    }
}

$ sudo ln -s /etc/nginx/sites-available/project-index.local /etc/nginx/sites-enabled/
$ sudo systemctl restart nginx