Scheduled Workflows in GitHub Actions

1. Introduction

Scheduled workflows in GitHub Actions allow you to automate tasks at specific times or intervals. This is particularly useful for tasks such as running tests, deploying applications, or generating reports.

2. Key Concepts

What is a Workflow?

A workflow is a configurable automated process made up of one or more jobs. Each job is composed of steps that can include actions, commands, and scripts.

Understanding Cron Syntax

GitHub Actions uses cron syntax to define the schedule for workflows. The syntax consists of five fields: minute, hour, day of month, month, and day of week.

3. Setting Up Scheduled Workflows

To create a scheduled workflow, follow these steps:

Create a new YAML file in your `.github/workflows` directory.
Add the `on` field with a `schedule` property using cron syntax.
Define jobs and steps as you would in any other workflow.

name: Scheduled Workflow
on:
  schedule:
    - cron: '0 * * * *'  # Runs every hour

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v2
      - name: Run a script
        run: echo "Hello, World!"

Note: Make sure to test your workflows thoroughly to avoid unexpected behaviors during scheduled runs.

4. Best Practices

Use descriptive names for your workflows.
Test workflows manually before scheduling them.
Use the `workflow_dispatch` event for manual triggers.
Monitor your workflows to catch any failures early.

5. FAQ

Can I schedule multiple workflows?

Yes, you can create multiple YAML files in the `.github/workflows` directory, each with its own schedule.

What happens if a workflow is scheduled while another is running?

Scheduled workflows will queue if another instance is already running unless configured otherwise.