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

✅ Chapter 2: Creating Your First GitHub Actions Workflow

🔍 Introduction

Now that you understand the fundamentals of CI/CD and GitHub Actions, it's time to get hands-on.

In this chapter, you will:

• Learn the basic structure of a GitHub Actions workflow
• Create your first real workflow from scratch
• Understand triggers (events), jobs, steps, and actions
• Customize workflows for different needs
• Troubleshoot and monitor your first workflow execution

By the end of this chapter, you’ll have confidence to automate simple build, test, and deployment tasks inside GitHub!

📋 Anatomy of a GitHub Actions Workflow

A GitHub Actions workflow is a YAML file stored inside your repository in:

bash

.github/workflows/

🔹 Key Components

📜 Basic Structure Example

yaml

name: Build and Test

on: [push]

jobs:

  build:

    runs-on: ubuntu-latest

    steps:

    - name: Checkout code

      uses: actions/checkout@v3

    - name: Install dependencies

      run: npm install

    - name: Run tests

      run: npm test

🚀 Step-by-Step: Creating Your First Workflow

Step 1: Create the Workflow Directory

In your repository:

bash

mkdir -p .github/workflows

Step 2: Create a Workflow File

Create a file named ci.yml:

bash

touch .github/workflows/ci.yml

Step 3: Write a Simple Workflow

Paste the following content into ci.yml:

yaml

name: CI Workflow

on:

  push:

    branches:

      - main

jobs:

  build:

    runs-on: ubuntu-latest

    steps:

    - name: Checkout repository

      uses: actions/checkout@v3

    - name: Set up Node.js

      uses: actions/setup-node@v3

      with:

        node-version: 16

    - name: Install packages

      run: npm install

    - name: Run unit tests

      run: npm test

Step 4: Push the Workflow

Commit and push the workflow file:

bash

git add .

git commit -m "Add CI workflow"

git push origin main

Step 5: Monitor Workflow Execution

Go to your GitHub repository → Click on the Actions tab → See your workflow running live!

You can view:

• Logs for each step
• Errors and warnings
• Status (Success, Failure)

🔔 Understanding Workflow Triggers

Workflows are event-driven.

🔹 Common Events

📋 Example: Scheduled Workflow

yaml

on:

  schedule:

    - cron: '0 0 * * *'  # Every day at midnight UTC

📋 Example: Manual Workflow Dispatch

yaml

on:

  workflow_dispatch:

Manually trigger this workflow from GitHub’s UI!

⚙️ Setting up Different Runners

🔹 Default GitHub-hosted Runners

GitHub provides ready-to-use virtual machines:

🔹 Using a Specific Runner

yaml

runs-on: ubuntu-latest

OR

yaml

runs-on: windows-latest

🧰 Using Pre-built Actions

GitHub Actions has a Marketplace full of reusable Actions.

Popular ones:

📋 Example: Using a Third-Party Action

yaml

- name: Upload Artifact

  uses: actions/upload-artifact@v3

  with:

    name: build-artifact

    path: dist/

Uploads the build folder (dist/) for later use!

🌟 Advanced Customization Basics

Once comfortable, you can:

• Add multiple jobs (build, test, deploy)
• Run jobs in parallel or sequentially
• Use conditionals (if: syntax)
• Create matrix builds (e.g., Node.js 14/16/18)
• Use caches to speed up workflows

📋 Example: Running Jobs in Parallel

yaml

strategy:

  matrix:

    node: [14, 16, 18]

Tests on Node 14, 16, and 18 simultaneously!

📈 Best Practices for First GitHub Workflows

🚀 Real-World Example: Node.js Build and Deploy Workflow

yaml

name: 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

  deploy:

    needs: build

    runs-on: ubuntu-latest

    steps:

    - uses: actions/checkout@v3

    - name: Deploy to server

      run: echo "Deploying application..."

Explanation:

• Build job runs first
• Deploy job waits for Build to succeed

📚 Common Issues When Starting

🚀 Summary: What You Learned in Chapter 2

• How to create your first GitHub Actions workflow
• Understanding jobs, steps, runners, and actions
• Setting triggers: push, pull_request, schedule
• Using pre-built Actions from Marketplace
• Best practices to avoid common issues

Congratulations! You've successfully built your first automated workflow with GitHub Actions!