document-build.yml

name: Document builder

on:
  push:
  pull_request:
  workflow_dispatch:

jobs:
  build-pdf:
    runs-on: ubuntu-latest
    timeout-minutes: 3
    steps:
      - uses: actions/checkout@v2
      - name: Determine container version
        run: echo DOCKER_IMAGE=$(cat .vscode/settings.json | python3 -c "import json, sys; print(json.load(sys.stdin)['vorlage-latex.buildcontainer'])") >> $GITHUB_ENV
      - name: Pull container image
        run: docker pull $DOCKER_IMAGE
      - name: Build PDF
        run: docker run --rm -v "$GITHUB_WORKSPACE/Latex:/latex" -u $(id -u ${USER}):$(id -g ${USER}) -e DISABLE_DIFFPDF=1 -e DISABLE_SYNCTEX=1 $DOCKER_IMAGE
      - name: Archive PDF
        uses: actions/upload-artifact@v2
        with:
          name: main.pdf
          path: Latex/main.pdf
  diff:
    # only runs if pdf build was successful
    needs: build-pdf
    if: |
      github.event_name == 'push' ||
      github.event_name == 'pull_request'
    runs-on: ubuntu-latest
    timeout-minutes: 3
    steps:
      - name: Checkout commit before push
        if: |
          github.event_name == 'push'
          && github.event.before != '0000000000000000000000000000000000000000'
        id: checkout-push
        uses: actions/checkout@v2
        with:
          ref: ${{ github.event.before }}
      - name: Checkout pull request base
        if: ${{ github.event_name == 'pull_request' }}
        id: checkout-pull-request
        uses: actions/checkout@v2
        with:
          ref: ${{ github.event.pull_request.base.ref }}
      - name: Stop execution on SetUp fail
        if: |
          steps.checkout-push.conclusion == 'skipped' &&
          steps.checkout-pull-request.conclusion == 'skipped'
        run: |
          echo "stop=true" >> $GITHUB_ENV
          echo "::warning::No checkout action ran, aborting diff. Either this workflow was triggered by a wrong event or there are no previous commits on the current branch."
      - name: Determine container version
        if: ${{ env.stop != 'true' }}
        run: echo DOCKER_IMAGE=$(cat .vscode/settings.json | python3 -c "import json, sys; print(json.load(sys.stdin)['vorlage-latex.buildcontainer'])") >> $GITHUB_ENV
      - name: Pull container image
        if: ${{ env.stop != 'true' }}
        run: docker pull $DOCKER_IMAGE
      - name: Build PDF
        if: ${{ env.stop != 'true' }}
        id: build-prev
        # NOTE there currently is no better way to mark a job as "allow failure" so we have to use this little hack.
        # the job will still appear as successful even if the diff build fails which might be slightly misleading
        run: |
          if ! docker run --rm -v "$GITHUB_WORKSPACE/Latex:/latex" -u $(id -u ${USER}):$(id -g ${USER}) -e DISABLE_DIFFPDF=1 -e DISABLE_SYNCTEX=1 $DOCKER_IMAGE; then
            echo "stop=true" >> $GITHUB_ENV
            echo "::warning::previous build failed, not generating diff"
          fi
      - name: Download new main.pdf
        if: ${{ env.stop != 'true' }}
        uses: actions/download-artifact@v2
        with:
          name: main.pdf
      - name: Generate diff
        if: ${{ env.stop != 'true' }}
        id: diff
        run: |
          if docker run --rm -v "$GITHUB_WORKSPACE:/data" --init -u $(id -u ${USER}):$(id -g ${USER}) $DOCKER_IMAGE xvfb-run diff-pdf -v -m -s --output-diff="/data/main-diff.pdf" "/data/Latex/main.pdf" "/data/main.pdf"; then
            echo "stop=true" >> $GITHUB_ENV
            echo "::warning::diff-pdf: no change detected"
          fi
      - name: Archive diff PDF
        if: ${{ env.stop != 'true' }}
        uses: actions/upload-artifact@v2
        with:
          name: main-diff.pdf
          path: main-diff.pdf