Running git pull from a php script

If you want apache (the user) to be able to pull from git, you'll have to create an ssh key for apache, then add that to the read only keys on github.

The flow is something like this (tweak to your needs)

usermod -s /bin/bash apache
su apache
cd ~
ssh-keygen # work through the keygen dance (added a dash)

Upload (tilde here refers to apache's homedir) ~/.ssh/id_rsa.pub to github and give apache access to whichever repos it needs to pull from.

Then you can test on the server by again su'ing to apache and running the git pull

su apache
cd ~/working-copy
git clone my-project

Once that's working you should be able to run a git pull through PHP.