AWS DevOps Demo App

This repository demonstrates a minimal AWS-based infrastructure and CI/CD pipeline for a simple Node.js application, using CloudFormation and versioned Infrastructure as Code.

Structure

• infra/ — CloudFormation stacks for VPC, RDS, and application infrastructure.
• diagrams/ — Architecture and pipeline diagrams.

Architecture

• VPC: Custom Virtual Private Cloud with public and private subnets.
• NAT: NAT Gateway provides internet access for resources in private subnets.
• RDS:
  • Multi-AZ MySQL instance deployed in private subnets for high availability (Production).
  • Single-AZ MySQL instance deployed in private subnet (Development/Testing).
• EC2:
  • Auto Scaling Group for production, behind an Application Load Balancer (ALB).
  • Separate Dev EC2 instance for testing and development deployments.
• Dev/Prod separation:
  Production and development environments are isolated. Dev EC2 instance is used for deployments from the dev branch.

Pipeline

• CI/CD pipeline packages the application as an artifact (e.g., zip archive) and uploads it to an S3 bucket.
• Deployment is triggered from the artifact in S3:
  • If code is pushed to the main branch, deployment goes to the production Auto Scaling Group (ASG).
  • If code is pushed to the dev branch, deployment goes to a separate Dev EC2 instance for testing.
• No build or test stage included; pipeline focuses on packaging and deployment.

Application

A simple Node.js (Express) demo app:

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

console.log('PORT FROM ENV:', process.env.PORT);

app.get('/', (req, res) => {
  res.send('Hello from AWS DevOps demo!');
});

const PORT = process.env.PORT || 8080;
app.listen(PORT, () => {
  console.log(`App running on port ${PORT}`);
});