How to configure an existing git repo to be shared by a UNIX group

Question

I have an existing git repo (a bare one) which has up to this point only been writable by me. I want to open it up to some UNIX user group, foo, so that all members of foo can push to it. I'm aware that I can easily set up a new git repo with:

git init --bare --shared=group repodir chgrp -R foo repodir 

But I need the equivalent operation for an existing repo dir.

Answer 1

Try this to make an existing repository in repodir work for users in group foo:

chgrp -R foo repodir                 # set the group chmod -R g+rw repodir                # allow the group to read/write chmod g+s `find repodir -type d`     # new files get group id of directory git init --bare --shared=all repodir # sets some important variables in repodir/config ("core.sharedRepository=2" and "receive.denyNonFastforwards=true") 

Answer 2

Merging @David Underhill and @kixorz answers, I made my own (definitive) solution.

It is for bare repos and non-bare repos. There are only little differences between them, but in this way is clearer.

BARE REPOSITORY

cd <repo.git>/                            # Enter inside the git repo git config core.sharedRepository group    # Update the git's config chgrp -R <group-name> .                   # Change files and directories' group chmod -R g+w .                            # Change permissions chmod g-w objects/pack/*                  # Git pack files should be immutable find -type d -exec chmod g+s {} +         # New files get directory's group id 

where:

• <repo.git> is the bare repository directory, typically on the server (e.g. my_project.git/).
• <group-name> is the group name for git users (e.g. users).

---

NON-BARE REPOSITORY

cd <project_dir>/                         # Enter inside the project directory git config core.sharedRepository group    # Update the git's config chgrp -R <group-name> .                   # Change files and directories' group chmod -R g+w .                            # Change permissions chmod g-w .git/objects/pack/*             # Git pack files should be immutable find -type d -exec chmod g+s {} +         # New files get directory's group id 

where:

• <project_dir> is the project directory containing the .git folder.
• <group-name> is the group name for git users (e.g. users).