What user runs the git hook?

Question

I have a post-update hook on my server, such that when I

git push

it does a pull on the live web directory. However, while the push always succeeds, the post-update hook sometimes fails.

The hook is pretty simple:

#!/bin/sh
#
# An example hook script to prepare a packed repository for use over
# dumb transports.
#
# To enable this hook, rename this file to "post-update".
cd /var/www
env -i git pull

I'm pushing updates from a variety of places, but sometimes I have to login as root on the server and manuall do a

env -i git pull

I only have to do it 20% of the time though. Any ideas why it would fail randomly? Also, how would I get it to log error messages, since it might be running as someone who can't write to the file system?

Answer 1

IIRC, git hooks are run by the git user in most setups. No idea why it would fail randomly, though.

Answer 2

The hooks are run as the user doing the push. If you have some kind of pre-made setup, that may be a user like git or gitosis, or it may be you. Just look at how you have the remote configured. (git remote show <remote-name> or just examine .git/config if you don't know) Presumably you're pushing via SSH, and there's a username@hostname in the URL.

P.S. It's pretty quick to demonstrate this - just clone a repo locally, throw a post-update hook in with an echo $USER or something similar, and try pushing as yourself or a different user (directly or through ssh).