A Python-Markdown Extension for Embedding Graphviz
python (59), markdown (6)Two of the tools I use most frequently in my writing (both public writing on this blog and notes I jot down for personal consumption) aregraphvizandmarkdown. The last few days I've been tossing around the idea of embedding Graphviz graphs into Markdown, and today I had a couple of hours to quickly throw it together.
The proof of concept,python-markdown-graphviz, is available on Github.
I chose to extendPython-Markdownbecause that is how I implemented my custom (and some have claimed, arbitrary) Markdown extensions I use for this blog.
The syntax for writing documents is straightforward: enclose the Graphviz graphs in a tag whose type corresponds with the Graphviz executable to render the snippet (dot,neato,lefty,dotty).
* hi * there digraph a { b -> c -> d } ## And a title digraph a { b -> c -> d } This is some textA simple example of usage is (requiring thatmdx_graphviz.pybe in the Python path):
importmarkdowntxt="* this is some\n
You can customize a few settings:
BINARY_PATHis the path to thedot,neato, etc executables (defaults to no path, i.e. assumes will be in$PATH).格式is the format for images created by Graphviz (defaults to png).WRITE_IMGS_DIRis the directory to write images into (defaults to local directory).BASE_IMG_LINK_DIRis the base directory for the links to the generated images (defaults to local directory).
An example of changing the defaults settings:
importmarkdowntxt="* this is some\n
There is a lot of room for improvement, in particular a few ideas:
- use the name of the graph (extracted from the graphviz syntax) for the filename instead of numeric filenames.
- option to specify dimensions of graphs, or at least specify the width and auto-calculate the height.
That's all there really is to it. I'll probably make some improvements as I keep using it, but would always be glad to have others build on it as well if it's useful.