Ref

• https://examregistration.github.com/certification/ACTIONS

Details

• What is GitHub Actions?

  • GitHub Actions are packaged scripts to automate tasks in a software-development workflow in GitHub.

• Where can you find GitHub Actions?
  

• Types of GitHub actions

  • There are three types of GitHub actions: container actions, JavaScript actions, and composite actions.

• What is a GitHub Actions workflow?

  • A GitHub Actions workflow is a process that you set up in your repository to automate software-development lifecycle tasks, including GitHub Actions.
  • With a workflow, you can build, test, package, release, and deploy any project on GitHub.
  • An event will trigger on all activity types for the event unless you specify the type or types.
  • A workflow must have at least one job. A job is a section of the workflow associated with a runner.
  • Each job will have steps to complete.

ここまで

• https://learn.microsoft.com/en-us/training/modules/github-actions-automate-tasks/2-github-actions-automate-development-tasks

構造

• workflow
  • job
    • step
      • action

• 例：workflow

name: A workflow for my Hello World file
on: push
jobs:
  build:
    name: Hello world action
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v1
    - uses: ./action-a
      with:
        MY_NAME: "Mona"

• ※build は job id となり、名前は任意。他のジョブから参照できる

• 例：Action（container action to run containerized code）

name: "Hello Actions"
description: "Greet someone"
author: "octocat@github.com"

inputs:
    MY_NAME:
      description: "Who to greet"
      required: true
      default: "World"

runs:
    uses: "docker"
    image: "Dockerfile"

branding:
    icon: "mic"
    color: "purple"

components

• Workflows
  • A workflow is an automated process that you add to your repository. A workflow needs to have at least one job, and different events can trigger it.
• Jobs
  • The job is the first major component within the workflow. A job is a section of the workflow that will be associated with a runner. (A job is a set of steps in a workflow that execute on the same runner)
  • You'll specify the runner with the runs-on: attribute.
• Steps
  • A step is an individual task that can run commands in a job.
  • Steps are executed in order and are dependent on each other.
  • Start with -, can be - uses: */- if: */- run: */- name: *
    • example: https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows#example-using-the-cache-action
• Actions
  • The actions inside your workflow are the standalone commands that are executed.
    • These standalone commands can reference GitHub actions
      • such as using your own custom actions
      • or community actions like the one we use in the preceding example, actions/checkout@v2.
    • You can also run commands such as run: npm install -g bats to execute a command on the runner.

Configure a GitHub Actions workflow

• cheduled events
  
• manual events
  • workflow_dispatch
  • repository_dispatch
• webhook events
  • check_run etc.
• Use conditional keywords
  • ${{ <expression> }}
  • as in the case of the if conditional, you can omit the expression syntax.
• Use specific versions of an action

steps:    
  # Reference a specific commit
  - uses: actions/setup-node@c46424eee26de4078d34105d3de3cc4992202b1e
  # Reference the major version of a release
  - uses: actions/setup-node@v1
  # Reference a minor version of a release
  - uses: actions/setup-node@v1.2
  # Reference a branch
  - uses: actions/setup-node@main

Exercise

Create a basic container action

• sample code

name: Post welcome comment
on:
  pull_request:
    types: [opened, reopened]
permissions:
  pull-requests: write
jobs:
  build:
    name: Post welcome comment
    runs-on: ubuntu-latest
    steps:
      - run: |
          gh pr comment $PR_URL --body "Welcome to the repository!"
          echo "PR_URL: $PR_URL"
          echo "PR_NUMBER: $PR_NUMBER"
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          PR_URL: ${{ github.event.pull_request.html_url }}
          PR_NUMBER: ${{ github.event.number }}

• github link
  • https://github.com/dudutou/skills-hello-github-actions/blob/main/.github/workflows/welcome.yml

感想

• トリガーじゃない（サンプル pull_request: types: [opened, reopened]）と、steps で実行するコマンドで環境変数の所で使う event のデータが正しく取れない（当たり前）
• echo でデバッグできる。環境変数や event のデータをログに出力できるから
• PR の reopened event は PR をクローズして再 open する場合に発行する event である。
  • draft から open する場合は発行されない
• GitHub CLI を使う場合に GH_TOKEN 環境変数を設定する必要がある

  • For each step that uses GitHub CLI, you must set an environment variable called GH_TOKEN to a token with the required scopes.