CI/CD Pipeline Setup with GitHub Actions: Automate Your Workflow from Code to Deployment

✅ Chapter 3: Building, Testing, and Deploying Applications

🔍 Introduction

Now that you’ve learned how to create a basic GitHub Actions workflow, it’s time to move toward real-world workflows: building, testing, and deploying actual applications.

In this chapter, you will learn:

• How to automate the build process
• How to run various types of tests (unit, integration, e2e)
• How to deploy to cloud providers, servers, or serverless platforms
• Best practices for build/test/deploy stages
• Real-world examples across different stacks

This chapter is where your pipelines come alive and start delivering real value.

🏗️ Part 1: Building Applications with GitHub Actions

Building an application involves compiling source code, bundling assets, preparing Docker images, or any preparatory steps before deployment.

🔹 Common Build Tasks by Application Type

📋 Basic Build Job Example

yaml

name: Build Node App

on: [push]

jobs:

  build:

    runs-on: ubuntu-latest

    steps:

    - uses: actions/checkout@v3

    - uses: actions/setup-node@v3

      with:

        node-version: '16'

    - run: npm install

    - run: npm run build

✅ Checks out code, installs dependencies, builds the project.

🧪 Part 2: Testing Applications with GitHub Actions

Running tests automatically is a core part of CI pipelines.

🔹 Types of Tests

📋 Example: Running Unit Tests for Node.js

yaml

- name: Run unit tests

  run: npm test

🔥 Parallel Testing and Matrix Builds

Sometimes, you want to test across multiple environments:

📋 Example: Matrix Strategy

yaml

strategy:

  matrix:

    node-version: [14, 16, 18]

steps:

  - uses: actions/setup-node@v3

    with:

      node-version: ${{ matrix.node-version }}

  - run: npm test

✅ Tests run in parallel across multiple Node versions!

🚀 Part 3: Deploying Applications with GitHub Actions

Once an application is built and tested, the next step is deployment.

🔹 Common Deployment Targets

📋 Example: Deploying to an EC2 Server

yaml

- name: Deploy to EC2

  run: |

    ssh -o StrictHostKeyChecking=no ${{ secrets.EC2_USER }}@${{ secrets.EC2_HOST }} "

      cd /var/www/app &&

      git pull origin main &&

      npm install &&

      pm2 restart app

    "

Important:

• Use GitHub Secrets to store credentials (EC2_USER, EC2_HOST).
• Ensure SSH keys are correctly set up.

🔹 Deploying to AWS S3 (Static Sites)

yaml

- name: Deploy to S3

  uses: jakejarvis/s3-sync-action@master

  with:

    args: --acl public-read --delete

  env:

    AWS_S3_BUCKET: ${{ secrets.S3_BUCKET }}

    AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}

    AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}

    SOURCE_DIR: './build'

✅ Uploads static assets to S3 automatically after a build!

📦 Best Practices for Build/Test/Deploy Stages

📋 Typical Three-Stage Pipeline

text

[ Build ] --> [ Test ] --> [ Deploy ]

Each stage is isolated into its own job and depends on success from the previous.

🌍 Real-World Example: Full CI/CD Pipeline for Node.js App

yaml

name: Full Node CI/CD

on:

  push:

    branches: [main]

jobs:

  build:

    runs-on: ubuntu-latest

    steps:

    - uses: actions/checkout@v3

    - uses: actions/setup-node@v3

      with:

        node-version: 16

    - run: npm install

    - run: npm run build

  test:

    needs: build

    runs-on: ubuntu-latest

    steps:

    - uses: actions/checkout@v3

    - run: npm test

  deploy:

    needs: test

    runs-on: ubuntu-latest

    steps:

    - name: Deploy to production

      run: ssh ${{ secrets.EC2_USER }}@${{ secrets.EC2_HOST }} 'bash deploy.sh'

✅ Simple, clear, scalable pipeline.

📚 Common Pitfalls and How to Avoid Them

🛤️ Recommended Next Steps After Mastering Build/Test/Deploy

• Learn caching strategies for dependencies
• Implement progressive deployment (blue/green, canary)
• Integrate notifications (Slack, Teams)
• Use approval gates before production deployment
• Add security scanning during builds

🚀 Summary: What You Learned in Chapter 3

• How to automate building applications using GitHub Actions
• How to run tests (unit, integration, e2e) across environments
• How to deploy applications to servers, cloud platforms, or static hosts
• Best practices for robust CI/CD pipelines
• Real-world full CI/CD example for Node.js apps

Building, testing, and deploying your application automatically isn’t just a dream anymore — it's reality with GitHub Actions!