That’s how Node.js Demo App was born — a small project that taught me how powerful GitHub Actions can be when paired with Docker.

📂 Project Overview

The application itself is straightforward — a Node.js web app that serves content on port 3000. But the real focus here wasn’t the app’s complexity, it was the automation pipeline behind it.

Repository: nodejs-demo-app

Structure:

.
├── app.js              # Main app logic
├── Dockerfile          # Container build instructions
├── package.json        # Node.js dependencies
└── .github/
    └── workflows/
        └── main.yml    # GitHub Actions workflow

🛠️ Tools & Technologies

• Node.js – For the web app itself

• Docker – To package and ship the app in containers

• DockerHub – To store and share the container image

• GitHub Actions – To automate the build, test, and push process

⚙️ The CI/CD Workflow

The pipeline lives in 📄 .github/workflows/main.yml and runs every time I push to main.

Here’s what happens behind the scenes:

1. Checkout Code – GitHub Actions pulls the latest code from the repository.

2. Setup Node.js – The runner gets a Node.js environment ready.

3. Install Dependencies – Runs npm install to set up required packages.

4. Run Tests – Validates the app to make sure nothing’s broken before deployment.

5. Authenticate with DockerHub – Uses my GitHub Secrets to log in securely.

6. Build Docker Image – Creates a production-ready container image.

7. Push to DockerHub – Publishes the image so it’s instantly available anywhere.

🔐 Secure Credentials

To make this work without exposing my password, I stored these secrets in GitHub:

🐳 Running the App Locally

If you want to run it locally without CI/CD, it’s just:

npm install
npm start

The app runs on http://localhost:3000.

Or, if you want to use my Docker image:

docker pull <dockerhub-username>/<image-name>
docker run -p 3000:3000 <dockerhub-username>/<image-name>

📦 The Result

The beauty of this setup is that I no longer have to worry about manual builds or deployments. Every time I push code to main, a new Docker image is automatically built, tested, and pushed to DockerHub.

This is the kind of automation that DevOps is all about — repeatable, reliable, and fast.

🙋‍♂️ About Me

I’m Harshal Vernekar, an aspiring DevOps & Cloud Engineer passionate about automation, CI/CD, and cloud-native technologies.