How to set up and deploy a Django application on a Linux server

sudo apt update && sudo apt upgrade

hostnamectl set-hostname <Host name>
# to verify
hostname

<ip address>    <host name>

adduser <username>
adduser <username> sudo
# Login to the system as the new user

scp <location of the generated key> <username>@ipaddress:~/.ssh/<name given to the keys>

PermitRootLogin no
PasswordAuthentication no

sudo apt install ufw
# Block all incoming and outgoing traffic except ssh 
sudo ufw default allow outgoing
sudo ufw default deny incoming
sudo ufw allow ssh

#  allow the port 8000 (Django uses this port run the development server)
sudo ufw allow 8000
# make sure to enable ssh before enabling ufw
sudo ufw enable

# after testing
sudo ufw delete allow 8000 && sudo ufw allow http/tcp
#for status
sudo ufw status

# in the root directory
pip freeze > requirements.txt

# Django==3.2.5
# psycopg2==2.9.1
# pytz==2021.1
# sqlparse==0.4.1

# -r for recursive file transfer.
scp -r <local project path> <username>@<ip address>:~/

git clone <remote repository url>

sudo apt install python3-pip
sudo apt install python3-venv
# Creating a virtual environment inside the project directory
python3 -m venv <projectDirectory>/<virtualEnvName>
# activation
source <projectDirectory>/<virtualEnvName>/bin/activate

pip install -r requirements.txt

DEBUG = False
ALLOWED_HOSTS = ['<ipAddress/domainName>']
# Static handled differently in production.
# third party storages or whitenoise requires additional settings
STATIC_ROOT = os.path.join(BASE_DIR,'static')

python manage.py collectstatic

sudo apt install postgresql postgresql-contrib
sudo -u postgres psql
CREATE DATABASE databasename;
CREATE USER username WITH PASSWORD 'password';
ALTER ROLE username SET client_encoding TO 'utf8';
ALTER ROLE username SET default_transaction_isolation TO 'read committed';
ALTER ROLE username SET timezone TO 'Asia/Kolkata';
GRANT ALL PRIVILEGES ON DATABASE databasename TO username;

# we have opened the port 8000 with ufw
python manage.py runserver 0.0.0.0:8000
# and test the application on <ipAddress>:8000

cd /etc/apache2/sites-available
# duplicate any of the default configuration file to get  started.
cp 000-default.conf <name_given_to_your_config>.conf

<!-- NB: all paths needs to be absolute -->
<VirtualHost *:80>

# The ServerName directive sets the request scheme, hostname and port that

# the server uses to identify itself. This is used when creating

# redirection URLs. In the context of virtual hosts, the ServerName

# specifies what hostname must appear in the request's Host: header to

# match this virtual host. For the default virtual host (this file) this

# value is not decisive as it is used as a last resort host regardless.

# However, you must set it for any further virtual host explicitly.

#ServerName www.example.com

ServerAdmin webmaster@localhost

DocumentRoot /var/www/html

# Available loglevels: trace8, ..., trace1, debug, info, notice, warn,

# error, crit, alert, emerg.

# It is also possible to configure the loglevel for particular

# modules, e.g.

#LogLevel info ssl:warn

ErrorLog ${APACHE_LOG_DIR}/error.log

CustomLog ${APACHE_LOG_DIR}/access.log combined

# For most configuration files from conf-available/, which are

# enabled or disabled at a global level, it is possible to

# include a line for only one particular virtual host. For example the

# following line enables the CGI configuration for this host only

# after it has been globally disabled with "a2disconf".

#Include conf-available/serve-cgi-bin.conf

<!-- right before the closing of </VirtualHost> we need to map Aliases for static and media -->

Alias /static /home/YOURUSER/YOURPROJECT/static

<Directory /home/YOURUSER/YOURPROJECT/static>

Require all granted

</Directory>

Alias /media /home/YOURUSER/YOURPROJECT/media

<Directory /home/YOURUSER/YOURPROJECT/media>

Require all granted

</Directory>

<Directory /home/YOURUSER/YOURPROJECT/YOURPROJECT>

<Files wsgi.py>

Require all granted

</Files>

</Directory>

WSGIScriptAlias / /home/YOURUSER/YOURPROJECT/YOURPROJECT/wsgi.py

WSGIDaemonProcess django_app python-path=/home/YOURUSER/YOURPROJECT python-home=/home/YOURUSER/YOURPROJECT/<VIRTUALENV>

WSGIProcessGroup django_app

</VirtualHost>

sudo chown :www-data <Path to your sqlite file>
sudo chmod 664 <Path to your sqlite file>

sudo chown :www-data <Path to your Django project>
sudo chown -R :www-data <Path to your media directory>
sudo chmod -R 774 <Path to your media directory>

server {

  server_name 127.0.0.1 yourhost@example.com;
  access_log /var/log/nginx/domain-access.log;

  location / {
    proxy_pass_header Server;
    proxy_set_header Host $http_host;
    proxy_redirect off;
    proxy_set_header X-Forwarded-For  $remote_addr;
    proxy_set_header X-Scheme $scheme;
    proxy_connect_timeout 10;
    proxy_read_timeout 10;

    # This line is important as it tells nginx to channel all requests to port 8000.
    # We will later run our wsgi application on this port using gunicorn.
    proxy_pass http://127.0.0.1:8000/;
  }

}

$ cd </path/to/djangoproject_subdirectory_with_wsgi.py>

$ gunicorn wsgi -b 127.0.0.1:8000 --pid /tmp/gunicorn.pid --daemon

# --daemon parameter tells gunicorn to run in the background
# So that gunicorn continues to run even if you close your ssh session
# (You cannot remain ssh-ed into your server all the time right!)

#add the env variables to the apache configuration
     SetEnv DB_NAME mydatabase
     SetEnv DB_USER mydbuser
     SetEnv DB_PASSWD sekrit
     SetEnv DB_HOST localhost
# reload and restart apache secrvice

import os, site, sys

site.addsitedir('/usr/local/virtualenvs/MYAPP-VIRTUALENV/lib/python2.7/site-packages')

BASE_DIR = os.path.dirname(os.path.abspath(__file__))
sys.path.append(os.path.join(BASE_DIR, '..'))

os.environ["DJANGO_SETTINGS_MODULE"] = "myapp.settings"  # see footnote [2]

from django.core.wsgi import get_wsgi_application
_application = get_wsgi_application()

env_variables_to_pass = ['DB_NAME', 'DB_USER', 'DB_PASSWD', 'DB_HOST', ]
def application(environ, start_response):
    # pass the WSGI environment variables on through to os.environ
    for var in env_variables_to_pass:
        os.environ[var] = environ.get(var, '')
    return _application(environ, start_response)

sudo touch /etc/config.json

{
    "SECRET_KEY":"sncalsjkn@#545jnsjkcn",
    #other keys goes here
}

import json
with open('/etc/config.json') as configFile:
    config = json.loads(configFile)
SECRET_KEY = config.get("SECRET_KEY")

# OTHER SETTINGS....

sudo systemctl restart apache2