GitHub Action Core Components

Automating your CI/CD pipelines with GitHub Actions starts with understanding its three building blocks: workflows, jobs, and steps. In this guide, we’ll break down each component, show examples, and highlight best practices for scalable, maintainable pipelines.

1. Workflow

A workflow is a YAML-defined automation triggered by repository events (such as push, pull_request, or scheduled events). You store workflows in the .github/workflows directory of your repo.

name: My Awesome App CI
on:
  push:
    branches: [ main ]
  pull_request:

jobs:
  unit-testing:
    name: Unit Testing
    runs-on: ubuntu-latest
    steps:
      - name: Checkout Repository
        uses: actions/checkout@v3

      - name: Setup Node.js
        uses: actions/setup-node@v3
        with:
          node-version: 20

      - name: Install Dependencies
        run: npm ci

      - name: Run Tests
        run: npm test

Workflows must reside in .github/workflows; files ending with .yml or .yaml will be automatically detected.

Key workflow fields:

Field	Description
`name`	Friendly name displayed in the Actions tab
`on`	Defines trigger events (e.g., `push`, `pull_request`)
`jobs`	A map of jobs to execute sequentially or in parallel

2. Job

A job is a sequence of steps that run on the same runner. Jobs execute in isolation, so artifacts and environment variables are not shared unless you explicitly pass them.

jobs:
  build-and-test:
    name: Build & Test
    runs-on: ubuntu-latest
    steps:
      # Steps defined here…

runs-on: Specifies the runner environment (GitHub-hosted or self-hosted).
Jobs can run in parallel by default, or you can enforce a sequence using needs.

By default, each job runs in a clean VM/container. Use needs to share artifacts or enforce order.

3. Steps

Steps are individual tasks executed within a job. They run sequentially on the job’s runner and support two main modes:

Actions (uses:) – Reusable extensions from GitHub Marketplace or your own.
Commands (run:) – Inline shell commands.

Example steps:

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

  - name: Setup Node.js
    uses: actions/setup-node@v3
    with:
      node-version: 20

  - name: Install Dependencies
    run: npm ci

  - name: Run Unit Tests
    run: npm test

Step Type	Description	Example
Action (`uses`)	Leverage community-built or official actions.	`uses: actions/checkout@v3`
Command (`run`)	Execute shell commands on the runner.	`run: npm test`

Popular Official Actions

You can extend your workflows with first-party or community actions. Here are a few commonly used ones:

Build and Push Docker Images: Build Docker images and publish to registries.
Create AKS Cluster: Configure Azure Kubernetes Service context.
Vault Secrets: Retrieve secrets from HashiCorp Vault.

The image outlines a three-step GitHub Actions process: building and pushing Docker images, creating an AKS cluster, and consuming Vault secrets.

Component Comparison

Component	Purpose	Example Usage
Workflow	Defines event triggers and jobs	`.github/workflows/ci.yml`
Job	Encapsulates steps on a runner	`runs-on: ubuntu-latest`
Step	Executes an action or shell command	`uses: actions/setup-node@v3` / `run:`

Next Steps

Now that you’ve seen how workflows, jobs, and steps interact, let’s create your first GitHub Actions workflow from scratch:

mkdir -p .github/workflows
cat << 'EOF' > .github/workflows/ci.yml
name: CI Pipeline
on: [push]
jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - run: echo "Hello, GitHub Actions!"
EOF

Commit and push to trigger your first automation run.

References

Watch Video

Adding a workflow status badge

Create and Run Workflow

Introduction

Continuous Integration with GitHub Actions

Continuous Deployment with GitHub Actions

Reusable Workflows and Reporting

Custom Actions

Self Hosted Runner

Security Guide

GitHub Actions - Core Concepts

GitHub Action Core Components

1. Workflow

2. Job

3. Steps

Popular Official Actions

Component Comparison

Next Steps

References

Watch Video

​1. Workflow

​2. Job

​3. Steps

​Popular Official Actions

​Component Comparison

​Next Steps

​References

Watch Video

1. Workflow

2. Job

3. Steps

Popular Official Actions

Component Comparison

Next Steps

References