• BlogNav:
• Archive of all posts

Per-repo update hooks with gitolite

Posted: Wed, 23 July 2014 | permalink | 3 Comments

Gitolite is a popular way to manage collections of git repositories entirely from the command line – it’s configured using configuration stored in a git repo, which is nicely self-referential. Providing per-branch access control and a wide range of addons, it’s quite a valuable system.

In recent versions (3.6), it added support for configuring per-repository git hooks from within the gitolite-admin repo itself – something which previously required directly jiggering around with the repo metadata on the filesystem. It allows you to “chain” multiple hooks together, too, which is a nice touch. You can, for example, define hooks for “validate style guidelines”, “submit patch to code review” and “push to the CI server”. Then for each repo you can pick which of those hooks to execute. It’s neat.

There’s one glaring problem, though – you can only use these chained, per-repo hooks on the pre-receive, post-receive, and post-update hooks. The update hook is special, and gitolite wants to make sure you never, ever forget it. You can hook into the update processing chain by using something called a “virtual ref”; they’re stored in a separate configuration directory, use a different syntax in the config file, and if you’re trying to learn what they do, you’ll spend a fair bit of time on them. The documentation describes VREFs as “a mechanism to add additional constraints to a push”. The association between that and the update hook is one you get to make for yourself.

The interesting thing is that there’s no need for this gratuitous difference in configuration methods between the different hooks. I wrote a very small and simple patch that makes the update hook configurable in exactly the same way as the other server-side hooks, with no loss of existing functionality.

The reason I’m posting it here is that I tried to submit it to the primary gitolite developer, and was told “I’m not touching the update hook […] I’m not discussing this […] take it or leave it”. So instead, I’m publicising this patch for anyone who wants to locally patch their gitolite installation to have a consistent per-repo hook UI. Share and enjoy!