Chapter 6: Automate everything with GitHub Actions

Objectives

After this chapter, you will set up a CI/CD process that automates everything when pushing code to GitHub:

  1. Build images for frontend and backend
  2. Push images to Amazon ECR
  3. Deploy containers to ECS Fargate
  4. Log and check status
  5. (Optional) Rollback if errors occur

1. Set up secrets in GitHub

Go to GitHub repo → Settings → Secrets and variables → Actions, add variables:

Name Value
AWS_ACCESS_KEY_ID Access Key of IAM user/role
AWS_SECRET_ACCESS_KEY Corresponding secret key
AWS_REGION ap-southeast-1
AWS_ACCOUNT_ID AWS account ID

🎯 IAM user should have permissions: AmazonEC2ContainerRegistryFullAccess, AmazonECS_FullAccess, CloudWatchLogsFullAccess

2. Create file .github/workflows/ci-cd.yml

name: CI/CD Pipeline

on:
  push:
    branches:
      - main

env:
  AWS_REGION: ${{ secrets.AWS_REGION }}
  AWS_ACCOUNT_ID: ${{ secrets.AWS_ACCOUNT_ID }}

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout source code
        uses: actions/checkout@v3

      - name: Configure AWS credentials
        uses: aws-actions/configure-aws-credentials@v2
        with:
          aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
          aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
          aws-region: ${{ env.AWS_REGION }}

      - name: Login to Amazon ECR
        uses: aws-actions/amazon-ecr-login@v1

      - name: Build and Push Frontend Image
        run: |
          docker build -t frontend-app ./frontend
          docker tag frontend-app:latest $AWS_ACCOUNT_ID.dkr.ecr.$AWS_REGION.amazonaws.com/frontend-app:latest
          docker push $AWS_ACCOUNT_ID.dkr.ecr.$AWS_REGION.amazonaws.com/frontend-app:latest

      - name: Build and Push Backend Image
        run: |
          docker build -t backend-app ./backend
          docker tag backend-app:latest $AWS_ACCOUNT_ID.dkr.ecr.$AWS_REGION.amazonaws.com/backend-app:latest
          docker push $AWS_ACCOUNT_ID.dkr.ecr.$AWS_REGION.amazonaws.com/backend-app:latest

      - name: Deploy to ECS
        run: |
          aws ecs update-service --cluster workshop-cluster --service frontend-service --force-new-deployment
          aws ecs update-service --cluster workshop-cluster --service backend-service --force-new-deployment

      - name: Check ECS Service Status
        run: |
          aws ecs describe-services --cluster workshop-cluster \ --services frontend-service backend-service

3. Logging and status checking

Check container logs:

  • Go to CloudWatch → Log groups → View log stream

Check ECS status:

aws ecs describe-services   --cluster workshop-cluster   --services frontend-service backend-service

4. Rollback (manual)

When deployment fails, you can rollback by:

  • Revert code → Push again
  • Or deploy old image from ECR (if tagged and saved previously)

📦 Tip: Use tags :v1, :v2, :rollback,… for easy rollback image control