link-checker-prs.yml

# This link check is run on all PRs but just for the files that were changed/added in the PR itself.
# Otherwise we had it too often that PR authors would see a failing link check that had nothing to do with their PR.

name: Link Check PR

on:
  push:
    branches:
      - main
  pull_request:
    branches:
      - main

jobs:
  linkChecker:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Get changed files
        id: changed-files
        uses: tj-actions/changed-files@v44

      - name: Filter markdown files only
        run: |
          md_files=`find ${{ steps.changed-files.outputs.all_changed_files }} -maxdepth 0 -name "*.md" | tr '\n' ' '`
          echo "MARKDOWN_FILES=$md_files" >> $GITHUB_ENV

      - name: Restore lychee cache
        uses: actions/cache@v4
        with:
          path: .lycheecache
          key: cache-lychee-${{ github.sha }}
          restore-keys: cache-lychee-

      - if: ${{ env.MARKDOWN_FILES != '' }}
        name: Link Checker
        uses: lycheeverse/lychee-action@v1.5.2
        with:
          args: --verbose --no-progress --exclude-mail --cache --max-cache-age 1d $MARKDOWN_FILES
          fail: true
          jobSummary: true
        env:
          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}