Submodule

The submodule is a feature that allows you to include another Git repository as a sub directory in your repository. If you want to use the contents of a library or another project you are developing, you can include it in the project while managing it separately from the main project.

Adding Submodule

To add a submodule, use the following command.

git submodule add

The information of the repository added as a submodule is described in .gitmodules.

Cloning a Repository Containing Submodule

If you clone a repository containing submodules in the same way as a normal repository, the submodule directory will be empty. If you want to clone the submodules together, use the --recursive option as follows.

git clone --recursive git@github.com:user/repo.git

If you have already cloned the main project and want to clone the contents of the sub-modules, execute the following command.

git submodule init
git submodule update

Updating Submodule

The first way to apply updates to the submodule is to go to the submodule directory and fetch and merge them.

cd submod
git fetch
git merge

The second method is to use submodule update as follows.

git submodule update --remote

If you update a local submodule, move to the submodule directory, commit, and push.

Remove Submodule

If you want to remove a submodule, first run deinit.

git submodule deinit submoddir

Next, remove the subdirectory from git with the following command.

git rm --cached submoddir

Finally, commit to reflect the changes.

git commit