Git submodule on remote bare

Question

I've setup my environment so I can push to a remote bare repository. I used these commands to set up the remote repository:

$ mkdir ~/website.git && cd ~/website.git
$ git init --bare

And

$ cat > hooks/post-receive

#!/bin/sh
GIT_WORK_TREE=/var/www/website git checkout -f

$ chmod +x hooks/post-receive

And on my local environment:

$ git remote add web ssh://website.com/home/website.git
$ git push web +master:refs/heads/master

Now I can deploy to this remote using git push web, and everything works great..

The problem: Submodules

I have a few submodules on my project that aren't getting initialized/updated at the remote repository. I can't run git submodule update on the bare because it's bare, and I can't run it on the /var/www/website folder because it's just a copy of the files and not a git repo.

Answer 1

I figured out another solution which looks rather clean to me. Just give git all the info it needs to perform the submodule stuff:

$ cd /path/to/your/git_work_tree
$ git --git-dir=/path/to/your/bare_repo.git --work-tree=. submodule init
$ git --git-dir=/path/to/your/bare_repo.git --work-tree=. submodule update

Answer 2

One possible way might be:

• to setup /var/www/website as a (non-bare) repo
• have your post-receive hook of your bare repo:
  • set GIT_DIR and GIT_WORK_TREE to the non-bare repo at /var/www/website
  • cd /var/ww/website
  • git pull ~/website
  • git submodule update (a bit like in "How do I init/update a git submodule in a working tree after pushing to a bare working directory?")

In other words:
Pull from the bare repo instead of trying to checkout from a bare repo: a non-bare repo should be able then to accommodate the git submodule update step.

An example script may look like

#!/bin/sh

# Get the latest code
cd /path/to/bare/repo

# Set git variables
GIT_WORK_TREE=/var/www/website
GIT_DIR=/var/www/website/.git

# Go to website and pull
cd /var/www/website
git pull /path/to/bare/repo
git submodule update --init --recursive

# Run additional build stuff here

Answer 3

I stumbled across this thread two days ago while I struggled with the same issue. After finally arriving at a nice, tidy solution, I wrote an article about it here:

Git push with submodules: a how-to guide

I realized that if I'm going to push to a bare repo, only to use post-receive to pull into a non-bare repo, I might as well just keep it simple and push directly to the non-bare repository. This is a clear case where the "best practice" of only pushing to a bare repo is only adding complexity.

In case of link rot, I'll paste my solution here, skipping over the bits where I run into all of the same problems that I'm sure you did.

---

First, let’s create a universal post-receive hook, one that I won’t need to change on a per-repository basis:

[aaron@aaronadams]$ cat > /usr/local/share/git-core/templates/hooks/post-receive.sample
#!/bin/sh
#
# An example hook script to update the working tree, including its
# submodules, after receiving a push.
#
# This hook requires core.worktree to be explicitly set, and
# receive.denyCurrentBranch to be set to false.
#
# To enable this hook, rename this file to "post-receive".

# Read standard input or hook will fail
while read oldrev newrev refname
do
:
done

# Unset GIT_DIR or the universe will implode
unset GIT_DIR

# Change directory to the working tree; exit on failure
cd `git config --get core.worktree` || exit

# Force checkout
git checkout --force

# Force update submodules
git submodule update --init --recursive --force
[aaron@aaronadams]$ chmod +x /usr/local/share/git-core/templates/hooks/post-receive.sample

Now let’s go ahead and break all the rules.

We’re going to initialize a non-bare Git repository, right in our website directory; make sure it can receive from git push; explicitly set its working tree to its parent directory; and enable our hook we just created.

[aaron@aaronadams]$ cd /var/www/vhosts/aaronadams.ca/sites/staging.aaronadams.ca
[aaron@aaronadams]$ git init && git config --bool receive.denyCurrentBranch false && git config --path core.worktree ../ && mv .git/hooks/post-receive.sample .git/hooks/post-receive
Initialized empty Git repository in /var/www/vhosts/aaronadams.ca/sites/staging.aaronadams.ca/.git/

Finally, on our local machine, we’ll change our remote to reflect the location of our new repository, and push.

[aaron@aaronadams]$ git remote set-url staging aaron@aaronadams.ca:sites/staging.aaronadams.ca
[aaron@aaronadams]$ git push staging master
remote: Submodule 'codeigniter' (git://github.com/EllisLab/CodeIgniter.git) registered for path 'codeigniter'
remote: Cloning into 'codeigniter'...
remote: Submodule path 'codeigniter': checked out 'fd24adf31255822d6aa9a5d2dce9010ad2ee4cf0'
To aaron@aaronadams.ca:sites/staging.aaronadams.ca
 * [new branch]      master -> master

Holy crap, it worked!

Not only is this method compatible with submodules, it also requires just one command to set up a new remote repository (which, okay, consists of four commands). It also keeps the repository and the working tree in the same place; and with no absolute paths required in our configuration or hook files, it’s now completely portable as well.

---

I hope this answer helps somebody as much as everyone else's Stack Exchange posts helped me over the last two days!