How to utilize local Sphinx extensions in Jupyter Book?

Hey all,

Sphinx has a great tutorial on developing extensions. Of note, it explains, by way of conf.py, how to utilize a local Sphinx extension (i.e. one not available on PyPI):

import os
import sys

sys.path.append(os.path.abspath("./_ext"))

extensions = ['helloworld']

Of course, one can do the latter part of appending an extension to the extension list in Jupyter Book. Your documentation explains that one should modify _config.yml like so:

sphinx:
  extra_extensions:
   - extension1
   - extension2

However, the important part — adding the local extension’s path — is impossible via _config.yml alone.

How would I go about using local Sphinx extensions as part of the Jupyter Book build process?

[hashslingrz]

Huh, well I’ll be darned, nice job @mmcky! Your PR works just fine for my local extension. Bang up job 😄

I also like your syntax choice more than my previous suggestion. 👍

[mmcky]

@choldgraf @hashslingrz I have added support for local_extensions in PR #1102. Let me know what you think re: syntax and then I can finalise with a test case etc.