Python Module Grapher

Fun script for plotting the internal and external dependency structure of python modules. This was made for fun; there are much better tools out there for plotting dependencies, like:

• pydeps by thebjorn
• py3-dependency-graph

^ You should use those. Also, check out Kevin Gullikson's visualization of the dependency structure of pypi for the pinnacle of dependency visualizations

Usage

Plotting a local repository:

graph = get_repo('path/to/repo')
plot_dependencies(graph, 'image_of_graph.png', style = 'kamada_kawai')

Plotting a repository from github:

graph = get_repo('mwetzel7r/python-module-grapher', from_github = True)
plot_dependencies(graph, 'image_of_graph.png', style = 'kamada_kawai')

• the pygithub API might get mad at you for making too many calls (you can get around that by providing authentication during the API call)
  • unless you're going overboard you should be fine

Examples

Here's a plot of this repo:

Here's an example of vsoch (a very cool researcher at Standford)'s pokemon repo:

It works best for smaller repos; it sort of gets unwieldy (but also kind of funny) when plotting large repos, like numpy:

How it works

• first, all of the python files in a repository are added to the graph dictionary
• then, all files in the graph dictionary are scanned with python's ast library, to find out what modules they're importing
• then, the graph is converted to a networkx object, which handles all the plotting

Dependencies

• matplotlib for plotting
• networkx for plotting/interacting with graphs
• PyGithub for scraping github repos

Limitations

• only works with python (relies on the python AST module)
• arranging all the nodes is a challenge and isn't always interpretable
• doesn't really handle variables and functions very well, so i just opted out of trying to plot them
• for large repos, there will probably be missing modules / mistakes it makes ¯\_(ツ)_/¯

Roadmap

• color nodes based on whether they're internal, external, or from the python standard lib
• plot variables/functions that are shared across scripts (im finding this to be sort of difficult)
• finding a way to organize nodes based on whether they all fall in the same directory
• convert to html/javascript and add to personal website 🤙