CI/CD Pipeline for a Dockerized App on AWS (From zero to production).

At the end of the project, you should be able to confidently say to your potential employer:

"I built a CI/CD pipeline using GitHub Actions to automatically test, build, and deploy a Dockerized application to AWS EC2, using Nginx and a blue/green strategy to achieve zero-downtime deployments."

Step 0.1 — Create a new project folder
On your local machine:

cd ~/OneDrive/Desktop
mkdir start-project1-cicd-from-scratch
cd start-project1-cicd-from-scratch

Initialize git:

git init

Step 0.2 — Create a NEW GitHub repository
Go to 👉 https://github.com/new

• Repository name:

start-project1-cicd-from-scratch

Visibility: Public
❌ Do NOT add README
❌ Do NOT add .gitignore
Create the repo.

Then connect local → GitHub:

git remote add origin https://github.com/dr-musa-bala/start-project1-cicd-from-scratch.git
git branch -M main

Step 0.3 — Confirm clean state
Run:

git status

You should see:

On branch main
No commits yet

✅ This is perfect.

🧱 PHASE 1 — Build the Minimal Node App (the “deploy target”)

Goal: Create a tiny app + test so CI has something real to run.
1) Create the project files
From inside start-project1-from-scratch run:

npm init -y
npm i express
npm i -D jest supertest

2) Create app.js.

code app.js

Paste:

const express = require("express");
const app = express();

app.get("/", (req, res) => {
  res.send("Project 1: CI/CD from scratch ✅");
});

app.get("/health", (req, res) => {
  res.status(200).send("OK");
});

module.exports = app;

*3) Create *server.js

code server.js

Paste:

const app = require("./app");

const PORT = process.env.PORT || 3000;

app.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});

4) Create a test file

Create folder + test:

mkdir test
code test/app.test.js

Paste:

const request = require("supertest");
const app = require("../app");

describe("GET /", () => {
  it("should return 200", async () => {
    const res = await request(app).get("/");
    expect(res.statusCode).toBe(200);
  });
});

5) Update package.jsonscripts
Open:

code package.json

Replace the scripts section with:

"scripts": {
  "start": "node server.js",
  "test": "jest"
}

6) Run locally (must pass)

npm test

You should now see output like:

PASS  test/app.test.js
✓ should return 200

npm start

Open in browser:
http://localhost:3000

You should see:
Project 1: CI/CD from scratch ✅

Stop server with:

• Ctrl + C

🧱 PHASE 2 — Dockerize the App (so CI/CD can ship it)
Goal: Package your app into a Docker image that runs the same everywhere.
1) Create Dockerfile (in project root)

Run:

code Dockerfile

This opens up VS Code.
Paste:

FROM node:18-alpine

WORKDIR /app

COPY package*.json ./
RUN npm ci --only=production

COPY . .

EXPOSE 3000

CMD ["npm", "start"]

Control + S to save.

2) Create .dockerignore (keeps image clean)

code .dockerignore

Paste:

node_modules
npm-debug.log
.git
.github
Dockerfile
docker-compose.yml
README.md

3) Create docker-compose.yml (local run)

code docker-compose.yml

Paste:

services:
  app:
    build: .
    ports:
      - "3000:3000"

Ensure at this stage that your Docker Desktop is powered on.

4) Build + run with Docker Compose
From project root:

docker compose up --build

Test in browser:

• http://localhost:3000

You should see:
Project 1: CI/CD from scratch ✅

Stop:

• Ctrl + C

Then clean up:

docker compose down

🧱 PHASE 3 — Push to GitHub + Add CI (GitHub Actions)
Goal: Every push runs tests automatically. If tests fail → pipeline fails.

1) Commit and push your current code
From project root:

git add .
git commit -m "Phase 2: Add Node app + tests + Docker setup"
git push -u origin main

Got an error.

Git is telling you the truth:

“I’m trying to push to a repository that does not exist at that URL.”

So either:

• the GitHub repo was not created, or
• the repo name is slightly different from what your local git thinks

We’ll fix this cleanly.

✅ STEP 1 — Check what remote URL Git is using

Run:

git remote -v

From the picture illustration above we can see where the problem is coming from wrong repo (repo not tallying).

Lets reset repo.
Enter the command:

git remote set-url origin https://github.com/dr-musa-bala/start-project1-cicd-from-scratch.git
git remote -v

Now we push again;

git push -u origin main

Check github under same repository.

🧱 PHASE 3 (CONT.) — Add GitHub Actions CI
1) Create the workflow file
From your project root:

mkdir -p .github/workflows
code .github/workflows/ci.yml

Paste this:

name: CI

on:
  push:
    branches: ["main"]
  pull_request:

jobs:
  test:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Setup Node
        uses: actions/setup-node@v4
        with:
          node-version: "18"
          cache: "npm"

      - name: Install dependencies
        run: npm ci

      - name: Run tests
        run: npm test

Save.

2) Commit + push

git add .github/workflows/ci.yml
git commit -m "Add GitHub Actions CI pipeline"
git push

3) Verify it’s running

Go to your GitHub repo → Actions tab → you should see a workflow run.

✅ If it turns green, you’re done.

✅ That means Project 1 now has real CI.

Now we level it up into CD: build a Docker image in CI and push it to **Docker Hub **automatically.

🧱 PHASE 4 — Docker Hub Build & Push (CD starts)

0) One-time setup on Docker Hub (important)

You need:

Docker Hub username
Docker Hub Access Token (not your password)

Create the token

Docker Hub → Account Settings → Security → New Access Token
Name it: github-actions-project1
Copy it (you won’t see it again).

1) Add GitHub Secrets (this is the “secret stuff” done correctly)

In your GitHub repo:
Settings → Secrets and variables → Actions → New repository secret

Create exactly these:

DOCKERHUB_USERNAME = your Docker Hub username (e.g., drmusabala)

DOCKERHUB_TOKEN = the access token you generated

✅ Secret names are fixed (left box)
✅ Secret values are your real details (right box)

2) Update workflow to build & push Docker image

Open the workflow:

code .github/workflows/ci.yml

Replace its content with this (CI + Docker push):

name: CI/CD

on:
  push:
    branches: ["main"]
    tags:
      - "v*.*.*"
  pull_request:

jobs:
  test-build-push:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: "18"
          cache: "npm"

      - name: Install dependencies
        run: npm ci

      - name: Run tests
        run: npm test

      - name: Log in to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

      - name: Build and push Docker image
        uses: docker/build-push-action@v6
        with:
          context: .
          push: true
          tags: |
            ${{ secrets.DOCKERHUB_USERNAME }}/project1-cicd:latest

3) Commit + push

git add .github/workflows/ci.yml
git commit -m "Add Docker build and push to Docker Hub"
git push

Very critical: Make sure in your secrets, it's your Docker Hub username you are using. Because I kept using my GitHub username and keeps getting errors.

You have successfully built, tested**, **containerized, authenticated, and pushed an image via CI. That’s core DevOps skill.

BONUS:
📌 Immediate next steps (important)
1️⃣ Lock this win into documentation (VERY important)

To be pasted in README.md

🚀 **Production CI/CD Pipeline — Docker & GitHub Actions**

This project demonstrates my ability to design, implement, and troubleshoot a production-grade CI/CD pipeline using modern DevOps tooling.

It reflects how CI/CD is actually done in real teams, including secure credential handling, container image lifecycle management, and failure debugging — not just “happy-path” automation.

🔍 What This Project Proves

- By completing this project end-to-end, I demonstrate the ability to:
- Build automated CI pipelines triggered on source control events
- Containerize applications using Docker best practices
- Securely authenticate and push images to Docker Hub
- Manage secrets and tokens using GitHub Actions
- Debug real CI failures (auth issues, build errors, test failures)
- Think in terms of repeatability, security, and automation
- This is the same workflow used in real production teams — simplified, but not diluted.

🧱 Technical Stack

- CI/CD: GitHub Actions
- Containerization: Docker
- Registry: Docker Hub
- Runtime: Node.js
- OS (CI runners): Linux
- Version Control: Git & GitHub
- 🔁 CI/CD Workflow (High-Level)

The pipeline automatically runs on every push to main.

- Pipeline Stages:
- Source checkout
- Node.js environment setup
- Dependency installation
- Test execution
- Secure login to Docker Hub
- Docker image build
- Docker image push to registry

📍 Workflow definition:

.github/workflows/ci.yml

🐳 Docker Image Automation

- The application is built into a Docker image and published automatically.
- Image build is fully automated
- Authentication uses Docker Hub access tokens
- No credentials are committed to source control

Example:

docker pull <dockerhub-username>/start-project1-cicd-from-scratch:latest

🔐 Security Practices

- Security was treated as a first-class concern, not an afterthought.
- Secrets stored in GitHub Actions Secrets
- Docker Hub authentication via access token, not password
- No sensitive data committed to Git
- Pipeline follows least-privilege principles

Secrets used:

DOCKERHUB_USERNAME

DOCKERHUB_TOKEN

📂 Repository Structure
.
├── .github/workflows/ci.yml   # CI pipeline definition
├── Dockerfile                # Production-ready Docker image
├── docker-compose.yml        # Local orchestration
├── index.js                  # Application entry point
├── package.json              # Dependencies & scripts
└── README.md

🧪 Testing Philosophy

- Tests are executed automatically during CI
- Pipeline fails fast if tests fail
- Enforces discipline expected in real engineering teams
- This models quality gates commonly used in production pipelines.

🧠 Engineering Mindset Demonstrated

This project emphasizes:

- Automation over manual steps
- Secure-by-default configuration
- Debugging over blind copy-paste
- Reproducibility across environments
- Clear separation between build, test, and release stages

🚀 Why This Matters to Employers

This project shows I can:

- Contribute to existing CI/CD systems
- Own small-to-medium automation tasks independently
- Understand how code moves from commit → container → registry
- Communicate infrastructure clearly through code and documentation
- It forms a strong foundation for:
- Continuous Deployment (CD)
- Cloud deployments (EC2, ECS, Kubernetes)
- Infrastructure as Code (Terraform)

📈 Next Steps (Planned Enhancements)

- Automated deployment to cloud (EC2)
- Zero-downtime deployment strategies
- Monitoring & health checks
- Infrastructure provisioning with Terraform

👤 About Me

**Dr. Musa Bala Audu**
Junior DevOps Engineer — Open to Remote Roles
GitHub: https://github.com/dr-musa-bala
Dev.to: https://dev.to/bala_audu_musa
Hashnode: https://hashnode.com/@musabalaaudu

Your README should include:

• Project overview
• CI workflow explanation
• Docker image link
• What problem it solves
• What you learned

✅ Step 1: Make sure you are in the project directory

In Git Bash, run:

pwd

You should see something like:

/Users/fresh/OneDrive/Desktop/start-project1-cicd-from-scratch

If not, go there:

cd ~/OneDrive/Desktop/start-project1-cicd-from-scratch

✅ Step 2: Confirm README exists

ls

You must see:

README.md

If you don’t, create it:

touch README.md

✅ Step 3: Open README and paste the content

Open with VS Code (recommended):

code README.md

👉 Paste the recruiter-tailored README I wrote for you
👉 Save the file (Ctrl + S)
👉 Close the editor

✅ Step 4: Stage the README
git add README.md

Check status:

git status

You should see:

new file: README.md

or

modified: README.md

✅ Step 5: Commit the README (important message)

Use a professional commit message:

git commit -m "docs: add production-grade README for CI/CD project"

✅ Step 6: Push to GitHub
git push origin main

If main is already tracking:

git push

✅ Step 7: Verify on GitHub

Open your repo in browser

Refresh the page

You should see:

README rendered automatically

Professional project overview visible to recruiters