End-to-End CI/CD Pipeline for Simple Node App Deployment on EKS using GitHub Actions

Table of Contents

• Repository Structure
• CI/CD Workflow
  • Build Job
  • Deployment Job
• Infrastructure Details
• GitOps Principles
• Notifications

Repository Structure

The repository is organized into several key directories:

├── app
│   ├── app.py
│   ├── calculator.js
│   ├── calculator.test.js
│   ├── Dockerfile
│   ├── Dockerfile-python
│   ├── index.js
│   └── package.json
├── kustomize
│   ├── base
│   │   ├── deploy.yaml
│   │   ├── ingress.yaml
│   │   ├── kustomization.yaml
│   │   └── svc.yaml
│   └── overlays
│       ├── dev
│       │   ├── deploy-dev.yaml
│       │   ├── ingress-dev.yaml
│       │   ├── kustomization.yaml
│       │   └── svc-dev.yaml
│       ├── prod
│       │   ├── deploy-prod.yaml
│       │   ├── ingress-prod.yaml
│       │   ├── kustomization.yaml
│       │   └── svc-prod.yaml
│       └── staging
│           ├── deploy-staging.yaml
│           ├── ingress-staging.yaml
│           ├── kustomization.yaml
│           └── svc-staging.yaml
├── README.md
├── terraform
│   ├── ingress-nginx.tf
│   ├── main.tf
│   ├── outputs.tf
│   ├── terraform.tf
│   └── variables.tf
└── VERSION

CI/CD Workflow

Build Job

The build job performs several key tasks:

1. Environment Setup: Node.js environment is set up and dependencies are installed.
2. Run Tests: Executes unit tests for the application.
3. Determine Version Increment: Checks the commit message to determine if the version needs to be incremented using Semantic Versioning scheme.
4. Docker Build and Push: Builds a Docker image and pushes it to a registry.

Deployment Job

The deployment job handles the following:

1. Terraform Setup: Initializes Terraform and sets up the backend with different state files.
2. Terraform Plan and Apply: Executes terraform plan and terraform apply to provision environment specific infrastructure.
3. Kubernetes Configuration: Configures kubectl to interact with the Kubernetes cluster.
4. Ingress Controller Setup: Uses Helm to install the ingress controller.
5. Application Deployment: Uses kubectl to deploy the Kustomized application manifests.

Infrastructure Details

• Dev Environment: Uses t3.small EC2 instances and deploys a single replica.
• Staging Environment: Uses t3.medium EC2 instances and deploys three replicas.
• Prod Environment: Uses t3.large EC2 instances and deploys three replicas.

DNS for all environments is automatically managed via Cloudflare and environment-specific subdomains are assigned and pointed to their respective LB hostname (using CNAME) ie., dev.afraz.dev, staging.afraz.dev and prod.afraz.dev.

Notifications

Slack notifications are configured to send updates at the end of each job. This provides immediate feedback on the success or failure of the pipeline and also updates on the DNS changes if applicable.

GitOps Principles

The pipeline adheres to GitOps principles, where Git serves as the single source of truth. Any change to the application or infrastructure is expected to be made through a Git commit.

Hit the Star! ⭐

If you are planning to use this repo for learning, please hit the star. Thanks!

Author by Harshhaa Reddy