How to Create Git Submodule Repo on Server

2018-02-10

When I set up this website, I find I need to have some nested git repo hierarchy. For example, the theme always has an individual repo and I also put the entire hexo website in a git repo. To make this hierarchy more manageable, it is a good practice to add sub git repo as submodules.

If you are using git server such as github, then you are set by simply typing the commands to set up two git repo and push to remote server and then use

1	git submodule add ./dir/to/submodule

to put everything not ignored to the server.

However, if you are using a git server set up by yourself, you may wonder how you should set the remote URLs for the main git repo and submodule git repo.

Instead of create two git repos in same directory to make the two repos for main and submodule are in the same level on server, we should create the server repos nested.

For example, if our main git repo named main, and our submodule repo named submodule, then we might need to perform the following actions and get the following hierarchies.

On Server:

# go to needed dir
cd /dir/to/remote/server 
# init main repo on server
git init --bare main.git 
# get into main.git
cd main.git 
# init submodule repo on server
git init --bare submodule.git

On Local Machine with initial or developed codes:

# get into directory and create file
cd main & touch readme.md
# init git repo locally
git init
# add remote repo
git remote add origin git@yourserver:/dir/to/remote/server/main.git 
# add modified file
git add readme.md
# commit first change
git commit -m "first commit"
# push change to remote server
git push origin master
# create local nested repo for submodule usage
mkdir submodule	
# create nested repo dir for submodule usage
cd submodule & touch readme.md
# init nested repo for submodule usage
git init
# add remote
git remote add origin git@yourserver:/dir/to/remote/server/main.git/submodule.git 
# modify file
git add readme.md	
# commit first modification in submodule
git commit -m "first submodule commit"		
# go back to main repo
cd ..
# add subomodule repo as submodule
git submodule add ./submodule	
# git add new submodule files and configs
git add ./submodule .gitmodule		
# commit this change
git commit -m "add submodule"
# push to git server
git push origin master

On another Local Machine which want to clone this repo:

1 2	# clone a repo with all submoduel git clone --recursive git@yourserver:/dir/to/remote/server/main.git

Then you will have a repo named main with submodule named submodule.