deoren wrote
The idea is to store the wiki pages in a github repo. Clone the repo to local machine, apply changes locally, push to github and pull from github on the wiki side to make the changes live.
If you're not wanting people to view the pages on github (as a wiki), why bother converting to Markdown? i.e. it's not hard to make the
$DokuWiki/data/pages (and index) directory version controlled on GitHub/Git.
$DokuWiki/data/media is tricky as it can lead to a very fat delta - you'd probably want git-media/git-submodule/git-fit/git-annexe/git-lfs etc.
Note - I did experiment with using GitHub for DokuWiki version control some time ago, but found using DokuWiki itself for for Change Control (Bureacracy/PageMod/StructuredData etc), and rsync/chron for backups, to be simpler and more resilient. A similar mechanism to backups is used to push changes to live versions, a slightly more complicated one provides a (modified) diff for individualised variations (i.e. I provide a private DokuWiki for clients that documents work I do for them and useful information - they get an email when I've updated "their" private Dokuwiki, and they then download and apply the latest diff using a provided script).
If you post some more details about what you use DokuWiki for you may get more useful information - I'd be surprised if others didn't have more experience on the subject than I. Creating a new post with a more relevant Subject may help too.
deoren wrote
Do you know of any wiki where this would be possible with the least amount of pain?
I suspect it's outside the scope of this forum to suggest more than I already have.
Assuming that you just want to use GitHub for (additional) version control and off-site backup - just use DokuWiki (how many Markup files would that require for GitHub? Two?).
Some useful links if you simply want to use DokuWiki as your wiki(?)
https://blog.timowens.io/writing-collaborative-documentation-with-dokuwiki-and-github/
http://tom-henderson.github.io/2015/04/08/dokuwiki-github.html
https://github.com/hoxu/dokuwiki2git