Storing private config files in .git directory?

Our git client (lazygit) has a need to store per-repo config files that override the global one, much like git itself. The easiest way to do that is to store those in a .git/lazygit.cfg file, and I'm wondering if there's any reason why this is a bad idea?

Another alternative would be to store the config values in .git/config (that's the path taken by git gui, for example), but since our config file format is yaml, this would require translation. It would be trivial for scalar values such as int or string, but I'm not sure how well this would work for more complex settings like lists of objects.

Any thoughts?

Stefan Haller <lists@haller-berlin.de> writes:

An obvious alternative is to have .lazygit directory next to .git directory which would give you a bigger separation, which can cut both ways.

On Mon, Jan 08, 2024 at 10:20:00AM -0800, Junio C Hamano wrote:

Just to spell out one of those ways: unlike ".git", we will happily check out ".lazygit" from an untrusted remote repository. That may be a feature if you want to be able to share project-specific config, or it might be a terrible security vulnerability if lazygit config files can trigger arbitrary code execution.

-Peff

On 10.01.24 12:08, Jeff King wrote:

Unless you don't version it and add it to .gitignore instead, which (I suppose) is what most people do with their .vscode/settings.json, for example.

-Stefan

On Thu, Jan 11, 2024 at 02:28:51PM +0100, Stefan Haller wrote:

A .gitignore will help with people accidentally adding their .lazygit directory. What I meant, though, was somebody _intentionally_ creating a malicious repository that would then execute arbitrary code when the victim cloned it. We prevent that from happening with .git/config because there's special handling that refuses to check out the name ".git" (or other filesystem-equivalent names). But ".lazygit" would not have that same protection.

-Peff

On Sun, Jan 07, 2024 at 02:03:20PM +0100, Stefan Haller wrote:

I have considered the same question for b4 as well, but I chose to just rely on git's config file handling instead of any other option. There's a large number of people who tend to deal with weird repository situations by blowing away the entire repo and then recloning it. They may remember to back up the .git/config file, but not really anything else.

So, that would be the only consideration against keeping anything in the .git directory.

-K

On 2024-01-07 08:03, Stefan Haller wrote:

In a worktree (created by "git worktree"), .git is a file not a directory.

Worktrees are designed to each have their own .git directory, which you can find with "git rev-parse --git-dir". If you just want a single, repo-wide config file, not a per-worktree config, you probably want to instead use "git rev-parse --git-common-dir" to find the "main" repo's .git directory.

The problem of finding a worktree's .git directory goes away if you use Git's own config system, though.

YAML is a horrid little format (hey, you asked for "thoughts"!), and IIRC Git's config file format only supports multi-line values with \-escaping and similar patterns, making it nearly impossible to directly embed YAML in Git's config file. Ideally, if you do use Git's own config then you really should just drop YAML altogether.

But you have a couple of options without going so far as translating all the YAML constructs you use into git-config ones. For example, you could replace all the newlines in a YAML blob with \n to make a single-line value that you could store in Git's config file. That complicates hand-editing the YAML though, if that's a use case you care about.

But even if you replace all the newlines with \n, in my experience there are always corner-case clashes when mixing file syntaxes (e.g. quoted strings are often problematic, and maybe some of your YAML values are themselves multi-line). If you want to use Git's own config file but stick with YAML, and you really don't care about directly editing the YAML, I suggest you encode the entire YAML blob in a robust single-line format, like base64, and store/retrieve that using "git config".

You could still support hand-editing the YAML with a command like "lazygit editconfig", too.

		M.