Just yesterday, I set up a cronjob to regularly push the RaumZeitLabor wiki to GitHub. Why? Because people wanted to search and aggregate the wiki like they would with normal text files. And because I like GitHubs repository graphs and wanted to use them for the wiki as well.

Installation

So lets get to it. I used Git-Mediawiki for the job, which allows you to interact with a MediaWiki-installation just like a normal git repository. The installation is pretty easy (I’m using Debian Testing):

sudo apt-get install libmediawiki-api-perl libdatetime-format-iso8601-perl make
wget -O Makefile "https://git.kernel.org/?p=git/git.git;a=blob_plain;f=contrib/mw-to-git/Makefile;hb=HEAD"
wget -O git-remote-mediawiki "https://git.kernel.org/?p=git/git.git;a=blob_plain;f=contrib/mw-to-git/git-remote-mediawiki;hb=HEAD"
sudo make install

Working with your wiki

That was it with the installation. Now you can clone a wiki like so:

git clone mediawiki::http://raumzeitlabor.de/w ~/wiki

Be careful, as this is usually not the URL you see when browsing the wiki, but the path you see when doing edits or similar operations on your wiki.

Wrong path

Correct path

To update your repository to the current state of the wiki, use

git pull --rebase

Automation

In the given scenario, the github repo was supposed to be updated regularly.

To do this, a deploy key pair for GitHub was needed.

tiefpunkt@tiefpunkt:~$ ssh-keygen -t rsa -C "wiki_deploy_key@tiefpunkt.vm.rzl"
Generating public/private rsa key pair.
Enter file in which to save the key (/home/tiefpunkt/.ssh/id_rsa): /home/tiefpunkt/wiki_deploy_key
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/tiefpunkt/wiki_deploy_key.
Your public key has been saved in /home/tiefpunkt/wiki_deploy_key.pub.

The public key of this key pair was then added to the GitHub repository.

Github deploy key

A custom SSH host was used to incorporate the key file. This was done in .ssh/config

Host wiki.gh
Hostname github.com
User git
IdentityFile ~/wiki_deploy_key

Initializing the git repository may take a while, depending on the size of your wiki. Don’t try Wikipedia.

tiefpunkt@tiefpunkt:~$ git clone mediawiki::http://raumzeitlabor.de/w ~/wiki
... Lots of text ...
tiefpunkt@tiefpunkt:~$ cd wiki
tiefpunkt@tiefpunkt:~/wiki$ git remote add github wiki.gh:raumzeitlabor/wiki.git
tiefpunkt@tiefpunkt:~/wiki$ git push github master
The authenticity of host 'github.com (207.97.227.239)' can't be established.
RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'github.com,207.97.227.239' (RSA) to the list of known hosts.
Everything up-to-date

The actual update script is pretty short.

#!/bin/sh
cd /home/tiefpunkt/wiki
git pull --rebase
git push github master

Don’t forget to make it executable.

Last but no least, a cronjob was scheduled to run that script once a day.

tiefpunkt@tiefpunkt:~$ crontab -e
no crontab for tiefpunkt - using an empty one

0 0 * * * /home/tiefpunkt/update-wiki.sh >> /home/tiefpunkt/update-wiki.log 2>>&1

crontab: installing new crontab