external-link-check.yml

# This link checks Microcks website links in Markdown HTML files once per day
# from: https://github.com/lycheeverse/lychee-action
# link checker used is 'lychee': https://github.com/lycheeverse/lychee

name: External Link Check
on:
  # This event will only trigger a workflow run if the workflow file is on the default branch.
  # ucomment the following line if you want to run the workflow manually
  # workflow_dispatch:
  # Run once a week on Sunday at 00h42 UTC (0:42 AM UTC aka 1:42 AM CEST with daylight saving time)
  schedule:
    - cron: "42 0 * * 0"

jobs:
  linkChecker:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      # Setup local cache in order to mitigate issues regarding rate limiting or to reduce stress on external resources
      # Restore the lychee cache if it exists for the current commit
      - name: Restore lychee cache
        id: restore-cache
        uses: actions/cache/restore@v4
        with:
          path: .lycheecache
          key: cache-lychee-${{ github.sha }}
          restore-keys: cache-lychee-
      
      # We do not need to build the site, so we can remove the Hugo build steps, thanks to the hugo check validation on push
      # However, retaining this comment for documentation purposes, just in case ;) 
      
      # Link Checker run with lychee action 
      - name: Link Checker
        id: lychee
        uses: lycheeverse/lychee-action@v1
        with:
          # Check all markdown and html files in repo
          # Exclude all files except those starting with http:// or https:// thanks to the --scheme option
          # Use cache but cache the results for 8 hours
          args: --base public --verbose --no-progress './**/*.md' './**/*.html' --scheme https --scheme http --cache --max-cache-age 8h
          # Use markdown as output format
          format: markdown
          # Use different output file path
          output: ./link-checker/report.md
          # Use a custom GitHub token to "avoid" rate limiting 
          token: ${{ secrets.CUSTOM_TOKEN }}
          # Don't fail action on broken links
          fail: false

      # Format the date for the issue title and store it in an environment variable
      - name: Format Date
        id: format_date
        run: echo "DATE=$(date +'%A, %e. %b %Y')" >> $GITHUB_ENV
      
      # Create an issue if there are broken links 
      - name: Create Issue From File
        if: env.lychee_exit_code != 0
        id: create_issue
        uses: peter-evans/create-issue-from-file@v5
        with:
          title: "External Link Check Report - ${{ env.DATE }}"
          content-filepath: ./link-checker/report.md
          labels: report, automated issue, contribution message, help wanted

      # Store the issue number in an environment variable 
      - name: Store Issue Number
        if: steps.create_issue.outputs.issue-number
        run: echo "ISSUE_NUMBER=${{ steps.create_issue.outputs.issue-number }}" >> $GITHUB_ENV
      
      # Add a comment to the issue with the contribution message  
      - name: Add contribution message as new comment
        if: ${{ env.ISSUE_NUMBER }} is not null
        run: gh issue comment "$NUMBER" --body-file "$BODY"
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GH_REPO: ${{ github.repository }}
          NUMBER: ${{ env.ISSUE_NUMBER }}
          BODY: "./.github/contribution_message.md"

      # Save the lychee cache for the next run    
      - name: Save lychee cache
        uses: actions/cache/save@v4
        if: always()
        with:
          path: .lycheecache
          key: ${{ steps.restore-cache.outputs.cache-primary-key }}