GitHub Actions

• GitHub Actions is a workflow automation service
• It helps build and execute workflows, CI/CD pipelines, etc

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Workflows §

• Workflow files should be located within the .github/workflows directory in the project root and have a .yml or .yaml extension
• Your workflow contains one or more jobs which can run in sequential order or in parallel
• A GitHub Actions workflow to be triggered when an event occurs in your repository

workflows is a special term, GitHub won't identify your workflows if they are placed in a directory with a different name

Example workflow file §

name: GitHub Actions Demo
on: [push]
jobs:
  Explore-GitHub-Actions:
    runs-on: ubuntu-latest
    steps:
      - run: echo "🎉 This is step 1"
      - run: echo "🐧 This is another step"
      - name: Check out repository code
        uses: actions/checkout@v4
      - name: List files in the repository
        run: |
          ls ${{ github.workspace }}
      - run: echo "🍏 This is the last step"
  Another-Job:
    runs-on: ubuntu-latest
    steps:
      - run: echo "🎉 This is step 1"

Refer to actions quick-start for links to pre-built workflows

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Jobs §

• A job is a set of steps in a workflow that is executed on the same runner
• Each job will run inside its own virtual machine runner
• A job has one or more steps that either run a script that you define or run an action, which is a reusable extension that can simplify your workflow.
• Steps are executed in order and are dependent on each other. Since each step is executed on the same runner, you can share data from one step to another
• You can configure a job’s dependencies with other jobs; by default, jobs have no dependencies and run in parallel with each other. When a job takes a dependency on another job, it will wait for the dependent job to complete before it can run

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Events §

• An event is a specific activity in a repository that triggers a workflow run

github.actor
github.event_name
runner.os
github.repository
github.workspace
job.status
github.ref
 
- run: echo "🍏 This job's status is ${{ job.status }}

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Refs §

1. https://stackoverflow.com/questions/55110729/how-do-i-cache-steps-in-github-actions