Written by Alex Hedley

Markdown to PDF via GitHub Actions and Pandoc

In this post I’ll run through converting a md file to a PDF using Pandoc and GitHub Actions.

If you need to convert files from one markup format into another, pandoc is your swiss-army knife. Pandoc can convert between the following formats:

This is useful if you’re writing up documentation and want to output to different file formats.

I found a useful example on a GitHub profile.

Create a new file called book.md and a folder called images.

Add you content.

Create a GitHub workflow:

name: Create PDF

on: push

jobs:
  convert_via_pandoc:
    runs-on: ubuntu-18.04
    steps:
      - uses: actions/checkout@v2
      - run: |
          mkdir output  # create output dir
          # this will also include README.md
          echo "FILELIST=$(printf '"%s" ' *.md)" >> $GITHUB_ENV
      - uses: docker://pandoc/latex:2.9
        with:
          args: --output=output/result.pdf ${ env.FILELIST }
      - uses: actions/upload-artifact@v2
        with:
          name: output
          path: output

Note: ${ var } needs double { }

As well as creating an artifact you could also create a release and upload that.

name: Create PDF

on: push

jobs:
  convert_via_pandoc:
    runs-on: ubuntu-18.04
    steps:
      - uses: actions/checkout@v2
      - run: |
          mkdir output # create output dir
          # this will also include README.md
          echo "FILELIST=$(printf '"%s" ' *.md)" >> $GITHUB_ENV
      - uses: docker://pandoc/latex:2.9
        with:
          args: --output=output/result.pdf ${ env.FILELIST }
      - uses: actions/upload-artifact@v2
        with:
          name: output
          path: output
      
      - name: Create Release
        id: create_release
        uses: actions/create-release@v1
        env:
          GITHUB_TOKEN: ${ secrets.GITHUB_TOKEN }
        with:
          tag_name: v0.1 #${ github.ref }
          release_name: Release v0.1 #${ github.ref }
          draft: true
          prerelease: false

      - name: Upload Release Asset
        id: upload-release-asset 
        uses: actions/upload-release-asset@v1
        env:
          GITHUB_TOKEN: ${ secrets.GITHUB_TOKEN }
        with:
          upload_url: ${ steps.create_release.outputs.upload_url }
          asset_path: output/result.pdf
          asset_name: Handbook.pdf
          asset_content_type: application/pdf

Note: ${ var } needs double { }

Note: There is a problem with the set-env Issue and PR.

One workaround is:

      - run: |
          echo "::set-env name=FILELIST::$(printf '"%s" ' *.md)"
        env:
          ACTIONS_ALLOW_UNSECURE_COMMANDS: 'true'

HTML

You might also want to create it as HTML:

Sample:

name: Create HTML

on: push

jobs:
  convert_via_pandoc:
    runs-on: ubuntu-18.04
    steps:
      - name: Checkout
        uses: actions/checkout@v2
        
      - name: Create output directory
        run: |
          mkdir output  # create output dir
          echo "FILELIST=book.md" >> $GITHUB_ENV
      
      - name: Pandoc
        uses: docker://pandoc/latex:2.9
        with:
          args: --output=output/index.html $ -s
      
      # copy the images from the repo to the output folder for inclusion in the artifact
      - name: Copy images dir to output dir
        run: cp -r images/ output/
      
      - name: Upload Artifact
        uses: actions/upload-artifact@v2
        with:
          name: Handbook
          path: output

Another option would be to add an extra arg (--extract-media) which takes a DIRECTORY: --extract-media=DIR, just set the folder to images: --extract-media=images and you will get the necessary files.

The file names do become random strings.

But then the path doesn’t work with the HTML.

Written on February 20, 2021

with : Pandoc, GitHub