Deployment Overview of Django on Server¶

Prerequisites and Basic Requirements¶

The deployment requires a Linux server running either Debian or Ubuntu. The following system components and privileges are necessary:

• Operating System: Debian or Ubuntu with APT package manager.
• Privileges: Root access or sudo privileges to install packages and manage system services.
• Python Environment: Python 3, python3-pip, libpq-dev, and python3-venv (for Debian) or python3-pexpect (for Ubuntu).
• Ports: Port 8000 is used internally by the Django application. Ports 80 and 443 are required for the Nginx reverse proxy and SSL termination.
• Domain: The application is configured to accept requests from https://{{ prefix }}{{ server_id }}.hostkey.in.

File and Directory Structure¶

The application and its supporting files are organized in the following locations:

• Project Root: /root/django_client/project
• Contains the main Django application code, manage.py, and configuration files.
• Virtual Environment: /root/django_client/venv
• Stores the isolated Python environment with Django and dependencies (Debian deployment).
• Static Files: /root/django_client/project/static
• Directory where collected static assets are stored.
• Nginx Configuration: /root/nginx
• Contains the compose.yml file for Docker deployment.
• Nginx User Config: /data/nginx/user_conf.d
• Stores custom Nginx configuration files, specifically {{ prefix }}{{ server_id }}.hostkey.in.conf.
• SSL Certificates: /etc/letsencrypt
• Mounted volume for Let's Encrypt certificates managed by the Nginx container.
• Systemd Service: /etc/systemd/system/django.service
• Defines the service unit for managing the Django application.

Application Installation Process¶

The Django application is installed and configured as follows:

1. Package Installation: System packages including Python 3, pip, and development libraries are installed via APT.
2. Environment Setup:
   • On Debian, a virtual environment is created at /root/django_client/venv.
   • Django is installed within this virtual environment using pip.
   • On Ubuntu, Django is installed globally using pip.
3. Project Initialization: A new Django project named django_client is created in /root/django_client/project.
4. Configuration:
   • settings.py is modified to set BASE_DIR and STATIC_ROOT.
   • ALLOWED_HOSTS is set to ['*'].
   • CSRF_TRUSTED_ORIGINS is configured to ['https://{{ prefix }}{{ server_id }}.hostkey.in'].
5. Database Setup: Database migrations are applied using python manage.py migrate --noinput.
6. Static Files: Static assets are collected into the static directory using python manage.py collectstatic --noinput.
7. Superuser Creation: An administrative user is created with the username root, email [email protected], and a password defined by the system configuration.

Docker Containers and Their Deployment¶

The reverse proxy and SSL management are handled by Docker containers using Docker Compose.

• Docker Installation: The Docker engine is installed on the server.
• Compose File: A compose.yml file is generated at /root/nginx/compose.yml.
• Service Definition:
• Image: jonasal/nginx-certbot:latest
• Restart Policy: unless-stopped
• Environment:
  • CERTBOT_EMAIL is set to [email protected].
  • Environment variables are loaded from /data/nginx/nginx-certbot.env.
• Network Mode: host
• Volumes:
  • nginx_secrets (external) mounted to /etc/letsencrypt.
  • /data/nginx/user_conf.d mounted to /etc/nginx/user_conf.d.
• Execution: The container stack is started using docker compose up -d from the /root/nginx directory.

Proxy Servers¶

Nginx acts as the reverse proxy and handles SSL termination for the Django application.

• Configuration Location: Custom Nginx configuration is located at /data/nginx/user_conf.d/{{ prefix }}{{ server_id }}.hostkey.in.conf.
• Routing: The configuration is modified to route all traffic (location /) to the backend Django application.
• SSL/TLS: SSL certificates are managed automatically by the nginx-certbot container using Let's Encrypt.
• Domain Mapping: The proxy is configured to serve the domain {{ prefix }}{{ server_id }}.hostkey.in.

Starting, Stopping, and Updating¶

The Django application is managed as a systemd service named django.

• Start the Service:

  systemctl start django.service
  

• Stop the Service:

  systemctl stop django.service
  

• Restart the Service:

  systemctl restart django.service
  

• Enable on Boot:

  systemctl enable django.service
  

• Check Status:

  systemctl status django.service
  

The service is configured to restart automatically if it fails (Restart=always). After any configuration changes or updates to the Nginx proxy, the Django service may need to be restarted to apply changes.