A Pandoc filter for Graphviz

This filter provides Graphviz code block support.

Features

• This filter changes the way to embed image according to the output format.
  • For html, it embeds svg elements directly.
  • For pdf/LaTeX, it embeds TikZ figures directly.
  • For other formats, it saves png images in working directory and embeds their links.
• The layout engine can be specified in block attributes.
• For wrong inputs, it embeds the error message as a code block. pandoc command does not fail.

Requirements

• pandoc
• graphviz
• dot2tex (pdf/LaTeX support)

On Debian, you can install the required packages as follows:

$ sudo apt install pandoc graphviz dot2tex ghc libghc-utf8-string-dev libghc-sha-dev libghc-pandoc-dev

Setup

Build filter

$ cd pandoc-filter-graphviz
$ ghc --make Main.hs -o pandoc-filter-graphviz

Note: -dynamic option is required in some environments.

Add TikZ to LaTeX template

You can skip this step if you do not use pdf/LaTeX.

• Copy default template

  $ mkdir -p ~/.pandoc/templates
  $ pandoc -D latex > ~/.pandoc/templates/default.latex
  

  Note, when you are using LaTeX beamer as target, replace the second command with:

  $ pandoc -D beamer > ~/.pandoc/templates/default.beamer
  

• Edit ~/.pandoc/templates/default.latex

  ...
  \usepackage{tikz} % insert this line
  
  \begin{document}
  ...

Usage

$ pandoc -F ./pandoc-filter-graphviz example.md -o example.html