GitHub Actions: Trigger Custom Workflows

Configure Workflows to Run One or More Events

What is GitHub?

  • Collaborative developer platform
  • Public and Private Repos
    • Free, Pro, Team, Enterprise
  • Home of GitHub Copilot
  • Source Code Control
  • CI/CD Automation
  • Package Management
  • Collaboration

What is GitHub Actions?

  • Entire platform and ecosystem for creating and running automated workflows within the GH Environment
  • An action is a script invoked from within a workflow

What are Workflows?

  • Automated scripts (actions) that run when specific events occur within a repo
  • Efficient way to automate development tasks
  • Common use cases:
    • CI/CD
    • Versioning and release management
    • Automation and notifications

GitHub Workflow Event Types

  • Push Events
  • Pull Request Events
  • Issue Events
  • Release Events
  • Workflow dispatch events (manual)
  • Scheduled Events
  • Webhook Events (external services)

Trigger Workflow when Commit is Pushed

  • Workflow runs when a new commit is pushed to a specific branch or repo
  • Use cases:
    • Running tests after every push
    • Deploy code and infrastructure to a staging environment
on:
    push:
        branches:
            - main
            - develop

Configure Workflows to Run for Scheduled Events

Scheduled-Based Workflow

  • Workflows run automatically at specific times or intervals
  • Use cases:
    • Running nightly builds
    • Performing hourly backups
on:
    schedule:
        - cron: '0 0 * * *' # Every day at midnight

Configure Trigger Custom Workflows

Manual Workflows

  • Workflow runs only when manually triggered by a user
  • Use cases:
    • Deploying to a production environment
    • Running a one-time automation script
on:
    workflow_dispatch:

Configure Workflows to Run for Webhook Events

Webhook-Triggered Workflows

  • Workflow runs when triggered by an external event from another service
  • Use cases:
    • Triggering a build when a new issue is created on GitHub
    • Deploying code to a server when a new version is released
on:
    webhook:
        url:https://example.com/my-webhook

Demonstrate a GitHub Event to Trigger a Workflow Based On a Practical Use Case

A Practical Example

Scenario: Automatically deploy a website to Netlify every time a new commit is pushed to the main branch Implementation: Push a new workflow to the GitHub repo; whenever you push a new commit to main, the workflow will automatically deploy the website to Netlify

on:
    push:
        branches: [main]

jobs:
    deploy:
        runs-on: ubuntu-latest

        steps:
            - uses: actions/checkout@3
            - name: Install dependencies
                run: npm install
            - name: Build website
                run: npm run build
            - name: Deploy to Netlify
                uses: netlify/actions/cli@v1.1
                with:
                    site_id: your_netlify_site_id
                    api_key: your_netlify_api_key
                    args: deploy --prod
  • branches: [main]: Deploy workflow when a push is made on the branch main
  • runs-on: ubuntu-latest: Runner that runs the following steps
  • uses: actions/checkout@3: GitHub hosted action

GitHub Actions workflow diagram

The GitHub Marketplace contains all of the available hosted actions Actions are stored in a repo’s .github/workflows directory