A project exploring the main roles that NGINX can play:
- Web server — serves static files
- Reverse proxy — hides the backends behind a single entry point
- Load balancer — spreads traffic across several identical instances
- Cache manager — stores backend responses to avoid hitting them every time
- Traffic compressor — gzip compression of text responses
- Secure entrypoint — HTTPS termination
A single NGINX instance sits in front of three identical containers running the same Express app that shows a web page presenting the main features of Nginx.
NGINX :
- terminates TLS,
- compresses responses,
- caches them,
- and load-balances incoming requests across the three backends.
┌──────────────────────────────┐
│ NGINX │
Browser ── :443 ───▶ │ TLS · gzip · cache · proxy │
(HTTP→HTTPS) │ load balancer │
└───────────────┬──────────────┘
│ least_conn
┌────────────────────────┼────────────────────────┐
▼ ▼ ▼
webapp1 :3001 webapp2 :3002 webapp3 :3003
(Express, Docker) (Express, Docker) (Express, Docker)
.
├── README.md
├── logo/ # source logos illustrating each NGINX role
└── webapp/
├── Dockerfile # builds the Node.js image
├── docker-compose.yaml # runs 3 instances of the same image
├── package.json
├── package-lock.json
├── server.js # Express server (reads APP_NAME / HOST_PORT)
└── public/ # static files served by Express
├── index.html
├── style.css
├── script.js
└── images/
- Docker and Docker Compose
- NGINX installed on the host (
sudo apt install nginxon Debian/Ubuntu/Mint)
git clone git@github.com:DevCTx/Nginx.gitcd webapp
docker compose up --buildA single image is built once and reused by all three services. Each container
receives a different APP_NAME and HOST_PORT via environment variables and is
published on a distinct host port:
| Service | Container port | Host port |
|---|---|---|
| webapp1 | 3000 | 3001 |
| webapp2 | 3000 | 3002 |
| webapp3 | 3000 | 3003 |
You can verify each instance directly: http://localhost:3001, :3002, :3003.
Copy the site configuration into /etc/nginx/sites-available/webapp, enable it,
and disable the default site to free port 80/8080:
sudo ln -s /etc/nginx/sites-available/webapp /etc/nginx/sites-enabled/
sudo rm -f /etc/nginx/sites-enabled/default
sudo mkdir -p /var/cache/nginx/webapp
sudo nginx -t
sudo systemctl reload nginxhttp://localhost:8080 (or https://localhost once TLS is configured).
docker compose downand delete folder
A workflow (test.yaml) has been integrated for automated integration tests (CI): with each push/PR on this Nginx repo, GitHub Actions mounts the entire stack and verifies that the Nginx config plays its 5 roles. If a role is interrupted, the workflow fails and warns.
- Triggers (on:) — runs on push, pull request, or manually (workflow_dispatch).
- Checkout — retrieve the code.
- Starts 3 containers of the same web app (3 instances, ports 3001/3002/3003) via docker compose.
- Waits for the 3 backends to respond (curl loop with retries).
- Installs and configures Nginx — generates a self-signed TLS certificate, loads your versioned nginx/webapp.conf, tests (nginx -t) and reboots.
- prints the Nginx log and destroys containers even if a test failed (guaranteed cleanup). [
if: always()]
| Test | What it validates |
|---|---|
| Port 8080 → 301 | HTTP redirection to HTTPS (secure input) |
| HTTPS → 200 | Reverse proxy + functional web server |
| content-encoding: gzip | Compression enabled |
| X-Cache-Status: HIT on 2nd call | Cache works |
| ≥ 2 backends reached | Distributed load balancing |
This repository is used as a submodule in PART2-Fundamentals of my DevOps repository: https://github.com/DevCTx/DevOps