check-for-redirects.yml

name: Docs Redirects

on:
  pull_request:
    types: [opened, synchronize]

jobs:
  check-approval:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v2
        with:
          fetch-depth: 0
          ref: ${{ github.head_ref }}

      - name: Check for renamed or deleted files
        id: check-renamed
        run: |
          if git diff --name-status ${{ github.event.pull_request.base.sha }} ${{ github.event.pull_request.head.sha }} -- docs/ | grep -E 'R|D'; then
          # output variable to pass to the next step that sets the diff-status to true
          echo "diff-status=true" >> "$GITHUB_OUTPUT"

          # diff work and parsing the paths to get them in the right shape
          diff_files=$(git diff --name-status ${{ github.event.pull_request.base.sha }} ${{ github.event.pull_request.head.sha }} -- docs/ | grep -E 'R|D')
          diff_files=$(echo "$diff_files" | sed 's|.mdx|/|g')
          diff_files=$(echo "$diff_files" | sed 's|docs/||g')
          # print the diff so each line is a new line in diff_files.txt
          echo "$diff_files" | tr " " "\n" > diff_files.txt

          # grab the filenames and plug them into our nginx template
          set +e
          while IFS= read -r line; do
          OLD=$(echo "$line" | awk '{print $2}')
          NEW=$(echo "$line" | awk '{print $3}')
          if [ -z "$NEW" ]; then
            NEW="OG-FILE-WAS-DELETED-REPLACE-ME-WITH-NEW-LOCATION"
          fi
          read -r -d '' TEMPLATE << EOM
          \`\`\`
          # TEST ME: https://stage.hasura.io/docs/3.0/$OLD
          location = /docs/3.0/$OLD {
              return 301 https://\$host/docs/3.0/$NEW;
          }
          \`\`\`
          EOM
          echo "$TEMPLATE" >> nginx.txt
          echo "This is a redirect:\n\n $TEMPLATE"
          done < diff_files.txt
          set -e
          echo "NGINX<<EOF" >> "$GITHUB_ENV"
          cat nginx.txt >> "$GITHUB_ENV"
          echo "EOF" >> "$GITHUB_ENV"
          else
          echo "diff-status=false" >> "$GITHUB_OUTPUT"
          fi

      - name: Delete comment if no redirects needed
        if: steps.check-renamed.outputs.diff-status == 'false'
        uses: hasura/comment-progress@v2.3.0
        with:
          github-token: ${{secrets.DOCS_GITHUB_TOKEN}}
          repository: 'hasura/ddn-docs'
          number: ${{ github.event.number }}
          id: redirects-summary
          delete: true

      - name: Add comment
        if: steps.check-renamed.outputs.diff-status == 'true'
        uses: hasura/comment-progress@v2.3.0
        with:
          github-token: ${{secrets.DOCS_GITHUB_TOKEN}}
          repository: 'hasura/ddn-docs'
          number: ${{ github.event.number }}
          id: redirects-summary
          message:
            "# Redirects 🔀\n\nHey, @robertjdominguez & @seanparkross — the following redirects will be needed for
            deployment:\n\n${{ env.NGINX }}"