MegaLinter workflow (meichthys/foss_photo_libraries)

The MegaLinter workflow from meichthys/foss_photo_libraries, explained and optimized by Latchkey.

CI health: C - fair

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Source: meichthys/foss_photo_libraries.github/workflows/regen.ymlLicense MITView source

What it does

This is the MegaLinter workflow from the meichthys/foss_photo_libraries repository, a real project running GitHub Actions. It is shown here with attribution under its MIT license.

Below, Latchkey shows a faster, safer version produced by its optimization engine.

The workflow

workflow (.yml)

---
# MegaLinter GitHub Action configuration file
# More info at https://megalinter.github.io
name: MegaLinter

on:
  # Trigger mega-linter at every push. Action will also be visible from Pull Requests to master
  push: # Comment this line to trigger action only on pull-requests (not recommended if you don't pay for GH Actions)
  pull_request:
    branches: [ master, main ]

env:
  # Comment env block if you do not want to apply fixes
  # Apply linter fixes configuration
  APPLY_FIXES: all # When active, APPLY_FIXES must also be defined as environment variable (in github/workflows/mega-linter.yml or other CI tool)
  APPLY_FIXES_EVENT: pull_request # Decide which event triggers application of fixes in a commit or a PR (pull_request, push, all)
  APPLY_FIXES_MODE: commit # If APPLY_FIXES is used, defines if the fixes are directly committed (commit) or posted in a PR (pull_request)

concurrency:
  group: ${{ github.ref }}-${{ github.workflow }}
  cancel-in-progress: true

jobs:
  regenerate_readme:
    name: Regenerate Readme
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          token: ${{ secrets.PAT || secrets.GITHUB_TOKEN }}
      - run: python generate_readme.py
      - uses: stefanzweifel/git-auto-commit-action@v4
        if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name == github.repository
        with:
          commit_message: "[skip ci] Regenerate readme"
          file_pattern: readme.md

  build:
    name: MegaLinter
    needs: regenerate_readme
    runs-on: ubuntu-latest
    steps:
      # Git Checkout
      - name: Checkout Code
        uses: actions/checkout@v3
        with:
          token: ${{ secrets.PAT || secrets.GITHUB_TOKEN }}
          fetch-depth: 0
          ref: ${{ github.ref }}

      # MegaLinter
      - name: MegaLinter
        id: ml
        # You can override MegaLinter flavor used to have faster performances
        # More info at https://megalinter.io/latest/flavors/
        uses: oxsecurity/megalinter/flavors/documentation@v6.15.0
        env:
          # All available variables are described in documentation
          # https://megalinter.io/latest/configuration/
          VALIDATE_ALL_CODEBASE: true # Set ${{ github.event_name == &#39;push&#39; &amp;&amp; github.ref == &#39;refs/heads/main&#39; }} to validate only diff with main branch
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          # ADD YOUR CUSTOM ENV VARIABLES HERE TO OVERRIDE VALUES OF .mega-linter.yml AT THE ROOT OF YOUR REPOSITORY

          # Upload MegaLinter artifacts
      - name: Archive production artifacts
        if: ${{ success() }} || ${{ failure() }}
        uses: actions/upload-artifact@v4
        with:
          name: MegaLinter reports
          path: |
            report
            mega-linter.log

      # Create pull request if applicable (for now works only on PR from same repository, not from forks)
      - name: Create Pull Request with applied fixes
        id: cpr
        if: steps.ml.outputs.has_updated_sources == 1 && (env.APPLY_FIXES_EVENT == 'all'
          || env.APPLY_FIXES_EVENT == github.event_name) && env.APPLY_FIXES_MODE
          == 'pull_request' && (github.event_name == 'push' ||
          github.event.pull_request.head.repo.full_name == github.repository) &&
          !contains(github.event.head_commit.message, 'skip fix')
        uses: peter-evans/create-pull-request@v4
        with:
          token: ${{ secrets.PAT || secrets.GITHUB_TOKEN }}
          commit-message: "[MegaLinter] Apply linters automatic fixes"
          title: "[MegaLinter] Apply linters automatic fixes"
          labels: bot
      - name: Create PR output
        if: steps.ml.outputs.has_updated_sources == 1 && (env.APPLY_FIXES_EVENT == 'all'
          || env.APPLY_FIXES_EVENT == github.event_name) && env.APPLY_FIXES_MODE
          == 'pull_request' && (github.event_name == 'push' ||
          github.event.pull_request.head.repo.full_name == github.repository) &&
          !contains(github.event.head_commit.message, 'skip fix')
        run: |
          echo "Pull Request Number - ${{ steps.cpr.outputs.pull-request-number }}"
          echo "Pull Request URL - ${{ steps.cpr.outputs.pull-request-url }}"

      # Push new commit if applicable (for now works only on PR from same repository, not from forks)
      - name: Prepare commit
        if: steps.ml.outputs.has_updated_sources == 1 && (env.APPLY_FIXES_EVENT == 'all'
          || env.APPLY_FIXES_EVENT == github.event_name) && env.APPLY_FIXES_MODE
          == 'commit' && github.ref != 'refs/heads/main' && (github.event_name
          == 'push' || github.event.pull_request.head.repo.full_name ==
          github.repository) && !contains(github.event.head_commit.message,
          'skip fix')
        run: sudo chown -Rc $UID .git/
      - name: Commit and push applied linter fixes
        if: steps.ml.outputs.has_updated_sources == 1 && (env.APPLY_FIXES_EVENT == 'all'
          || env.APPLY_FIXES_EVENT == github.event_name) && env.APPLY_FIXES_MODE
          == 'commit' && github.ref != 'refs/heads/main' && (github.event_name
          == 'push' || github.event.pull_request.head.repo.full_name ==
          github.repository) && !contains(github.event.head_commit.message,
          'skip fix')
        uses: stefanzweifel/git-auto-commit-action@v4
        with:
          branch: ${{ github.event.pull_request.head.ref || github.head_ref || github.ref
            }}
          commit_message: "[MegaLinter] Apply linters fixes"

  # We want that the only edit points are: readme.tpl and projects.json
  # If someone edits readme.md directly the job fails
  validate:
    name: Validate readme.md
    needs: regenerate_readme
    runs-on: ubuntu-latest
    steps:
      - name: Checkout Code
        uses: actions/checkout@v3
        with:
          token: ${{ secrets.PAT || secrets.GITHUB_TOKEN }}
          fetch-depth: 0
          ref: ${{ github.ref }}

      - name: Set up Python
        uses: actions/setup-python@v4
        with:
          python-version: "3.x"

      - name: Run consistency tests
        run: python3 test_generate_readme.py TestReadmeConsistency -v

      - name: Run all tests
        run: python3 test_generate_readme.py -v

The same workflow, on Latchkey

Estimated ~20% faster on cache hits, plus fewer wasted runs and a safer supply chain. Added and changed lines are highlighted.

---
# MegaLinter GitHub Action configuration file
# More info at https://megalinter.github.io
name: MegaLinter
 
on:
  # Trigger mega-linter at every push. Action will also be visible from Pull Requests to master
  push: # Comment this line to trigger action only on pull-requests (not recommended if you don't pay for GH Actions)
  pull_request:
    branches: [ master, main ]
 
env:
  # Comment env block if you do not want to apply fixes
  # Apply linter fixes configuration
  APPLY_FIXES: all # When active, APPLY_FIXES must also be defined as environment variable (in github/workflows/mega-linter.yml or other CI tool)
  APPLY_FIXES_EVENT: pull_request # Decide which event triggers application of fixes in a commit or a PR (pull_request, push, all)
  APPLY_FIXES_MODE: commit # If APPLY_FIXES is used, defines if the fixes are directly committed (commit) or posted in a PR (pull_request)
 
concurrency:
  group: ${{ github.ref }}-${{ github.workflow }}
  cancel-in-progress: true
 
jobs:
  regenerate_readme:
    timeout-minutes: 30
    name: Regenerate Readme
    runs-on: latchkey-small
    steps:
      - uses: actions/checkout@v4
        with:
          token: ${{ secrets.PAT || secrets.GITHUB_TOKEN }}
      - run: python generate_readme.py
      - uses: stefanzweifel/git-auto-commit-action@v4
        if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name == github.repository
        with:
          commit_message: "[skip ci] Regenerate readme"
          file_pattern: readme.md
 
  build:
    timeout-minutes: 30
    name: MegaLinter
    needs: regenerate_readme
    runs-on: latchkey-small
    steps:
      # Git Checkout
      - name: Checkout Code
        uses: actions/checkout@v3
        with:
          token: ${{ secrets.PAT || secrets.GITHUB_TOKEN }}
          fetch-depth: 0
          ref: ${{ github.ref }}
 
      # MegaLinter
      - name: MegaLinter
        id: ml
        # You can override MegaLinter flavor used to have faster performances
        # More info at https://megalinter.io/latest/flavors/
        uses: oxsecurity/megalinter/flavors/documentation@v6.15.0
        env:
          # All available variables are described in documentation
          # https://megalinter.io/latest/configuration/
          VALIDATE_ALL_CODEBASE: true # Set ${{ github.event_name == &#39;push&#39; &amp;&amp; github.ref == &#39;refs/heads/main&#39; }} to validate only diff with main branch
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          # ADD YOUR CUSTOM ENV VARIABLES HERE TO OVERRIDE VALUES OF .mega-linter.yml AT THE ROOT OF YOUR REPOSITORY
 
          # Upload MegaLinter artifacts
      - name: Archive production artifacts
        if: ${{ success() }} || ${{ failure() }}
        uses: actions/upload-artifact@v4
        with:
          name: MegaLinter reports
          path: |
            report
            mega-linter.log
 
      # Create pull request if applicable (for now works only on PR from same repository, not from forks)
      - name: Create Pull Request with applied fixes
        id: cpr
        if: steps.ml.outputs.has_updated_sources == 1 && (env.APPLY_FIXES_EVENT == 'all'
          || env.APPLY_FIXES_EVENT == github.event_name) && env.APPLY_FIXES_MODE
          == 'pull_request' && (github.event_name == 'push' ||
          github.event.pull_request.head.repo.full_name == github.repository) &&
          !contains(github.event.head_commit.message, 'skip fix')
        uses: peter-evans/create-pull-request@v4
        with:
          token: ${{ secrets.PAT || secrets.GITHUB_TOKEN }}
          commit-message: "[MegaLinter] Apply linters automatic fixes"
          title: "[MegaLinter] Apply linters automatic fixes"
          labels: bot
      - name: Create PR output
        if: steps.ml.outputs.has_updated_sources == 1 && (env.APPLY_FIXES_EVENT == 'all'
          || env.APPLY_FIXES_EVENT == github.event_name) && env.APPLY_FIXES_MODE
          == 'pull_request' && (github.event_name == 'push' ||
          github.event.pull_request.head.repo.full_name == github.repository) &&
          !contains(github.event.head_commit.message, 'skip fix')
        run: |
          echo "Pull Request Number - ${{ steps.cpr.outputs.pull-request-number }}"
          echo "Pull Request URL - ${{ steps.cpr.outputs.pull-request-url }}"
 
      # Push new commit if applicable (for now works only on PR from same repository, not from forks)
      - name: Prepare commit
        if: steps.ml.outputs.has_updated_sources == 1 && (env.APPLY_FIXES_EVENT == 'all'
          || env.APPLY_FIXES_EVENT == github.event_name) && env.APPLY_FIXES_MODE
          == 'commit' && github.ref != 'refs/heads/main' && (github.event_name
          == 'push' || github.event.pull_request.head.repo.full_name ==
          github.repository) && !contains(github.event.head_commit.message,
          'skip fix')
        run: sudo chown -Rc $UID .git/
      - name: Commit and push applied linter fixes
        if: steps.ml.outputs.has_updated_sources == 1 && (env.APPLY_FIXES_EVENT == 'all'
          || env.APPLY_FIXES_EVENT == github.event_name) && env.APPLY_FIXES_MODE
          == 'commit' && github.ref != 'refs/heads/main' && (github.event_name
          == 'push' || github.event.pull_request.head.repo.full_name ==
          github.repository) && !contains(github.event.head_commit.message,
          'skip fix')
        uses: stefanzweifel/git-auto-commit-action@v4
        with:
          branch: ${{ github.event.pull_request.head.ref || github.head_ref || github.ref
            }}
          commit_message: "[MegaLinter] Apply linters fixes"
 
  # We want that the only edit points are: readme.tpl and projects.json
  # If someone edits readme.md directly the job fails
  validate:
    timeout-minutes: 30
    name: Validate readme.md
    needs: regenerate_readme
    runs-on: latchkey-small
    steps:
      - name: Checkout Code
        uses: actions/checkout@v3
        with:
          token: ${{ secrets.PAT || secrets.GITHUB_TOKEN }}
          fetch-depth: 0
          ref: ${{ github.ref }}
 
      - name: Set up Python
        uses: actions/setup-python@v4
        with:
          cache: 'pip'
          python-version: "3.x"
 
      - name: Run consistency tests
        run: python3 test_generate_readme.py TestReadmeConsistency -v
 
      - name: Run all tests
        run: python3 test_generate_readme.py -v

What changed

Run on Latchkey managed runners with one line (runs-on), which apply the fixes below automatically and self-heal transient failures. This example uses latchkey-small; pick the runner size that fits the job.
Cache dependency installs on the setup step so they are served from cache.
Add a job timeout so a hung step cannot burn hours of runner time.

3 third-party actions are referenced by a movable tag. Pin them to the commit SHA (Latchkey resolves and applies this automatically) so a repointed tag cannot change what runs.

This workflow runs 3 jobs per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow

actions/checkout stefanzweifel/git-auto-commit-action actions/upload-artifact peter-evans/create-pull-request actions/setup-python