✨ GitHub Actions - Explained✨

GitHub Actions is the built-in automation powerhouse of GitHub. If your organization is standardizing on GitHub, this is the obvious CI/CD choice. No excuses, no bolt-on tools, no duct tape.

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🤔 What Are GitHub Actions?

The word actions has two meanings in GitHub. Do not confuse them.

1️⃣ Actions (capital A)

The GitHub service that lets you build CI/CD workflows directly inside your repo.

2️⃣ actions (lowercase a)

Reusable building blocks that do actual work, for example:

• Run scripts or commands
• Build and upload artifacts
• Authenticate to Azure or AWS
• Set up runtimes like Node.js or Java

There is a full Marketplace of prebuilt actions. Use them instead of reinventing garbage.

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🧩 Core Components of GitHub Actions

Here is the real structure. Memorize it.

🔹 workflow

A YAML file that defines the entire automation pipeline.
Triggered by events like:

• push
• pull_request
• manual dispatch

Stored in:
.github/workflows/*.yml

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🔹 job

A major unit of work inside a workflow.

• Jobs can run in parallel
• Or sequentially using dependencies

Each job runs on its own virtual machine or container.

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🔹 step

A single task inside a job.
Examples:

• Run a shell command
• Call a reusable action
• Upload an artifact

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🔹 action

A reusable function packaged as code.
Examples:

• actions/checkout
• actions/setup-node
• azure/login

Use official ones. Random third-party junk is a security risk.

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🔹 variable

A named value reused across steps.
Used for:

• Config values
• Paths
• Environment flags

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🔹 secret

An encrypted variable for sensitive data.
Used for:

• Tokens
• Passwords
• API keys

Never hardcode secrets. Ever.

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🛠️ How to Create a GitHub Actions Workflow

Follow this flow. No shortcuts.

1️⃣ Create a Repository

You need:

• A GitHub account
• A repository
• Default branch, usually main

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2️⃣ Create Workflow Directory

.github/workflows

GitHub only detects workflows from here.

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3️⃣ Create a YAML File

Name it anything you want, but it must end with .yml
Example:

ci-pipeline.yml

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4️⃣ Define the Workflow

Write your workflow logic in YAML.

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5️⃣ Commit and Push

Until it is committed, nothing runs.
No commit, no CI/CD. Period.

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📄 Example: Simple GitHub Actions Workflow

name: Basic GitHub Actions workflow

on: [push]

jobs:
  say_hello:
    runs-on: macos-latest

    steps:
    - name: Checkout The Repository
      uses: actions/checkout@v2

    - name: Print Hello (Run Build Script)
      run: |
        echo "Hello, GitHub Actions!"

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🔍 What This Workflow Actually Does

🏷️ Workflow Name

name: Basic GitHub Actions workflow

Displayed in the Actions tab in GitHub.

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⚡ Trigger

on: [push]

Runs on every push to any branch.

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🧱 Job Definition

jobs:
  say_hello:

Creates a job named say_hello.

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💻 Runner OS

runs-on: macos-latest

Runs on an MacOS VM.
Ubuntu or macOS also work if your stack demands it.

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🔄 Steps Breakdown

Step 1: Checkout Repo

- name: Checkout The Repository
  uses: actions/checkout@v2

Pulls your repo code into the runner.
Without this, your job runs on an empty machine.

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Step 2: Run Command

- name: Print Hello (Run Build Script)
  run: |
    echo "Hello, GitHub Actions!"

Executes a shell command.
Replace this with:

• build
• test
• deploy

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🔗 Turning This Into Real CI/CD

To build a real pipeline, you stack more steps:

• 🏗️ Build code
• 🧪 Run tests
• 📦 Package artifacts
• 🚀 Deploy to cloud
• 📊 Notify Slack or Teams

Once triggered, monitor everything under the Actions tab.

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🎯 Bottom Line

GitHub Actions gives you:

• Native CI/CD inside GitHub
• Zero extra tooling
• Full automation control
• Scalable pipelines
• Massive action ecosystem

If your org is on GitHub and not using Actions, that is pure operational incompetence.