--- stage: Verify group: Pipeline Execution info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments type: reference --- # Using Git submodules with GitLab CI/CD **(FREE)** Use [Git submodules](https://git-scm.com/book/en/v2/Git-Tools-Submodules) to keep a Git repository as a subdirectory of another Git repository. You can clone another repository into your project and keep your commits separate. ## Configure the `.gitmodules` file When you use Git submodules, your project should have a file named `.gitmodules`. You might need to modify it to work in a GitLab CI/CD job. For example, your `.gitmodules` configuration might look like the following if: - Your project is located at `https://gitlab.com/secret-group/my-project`. - Your project depends on `https://gitlab.com/group/project`, which you want to include as a submodule. - You check out your sources with an SSH address like `git@gitlab.com:secret-group/my-project.git`. ```ini [submodule "project"] path = project url = ../../group/project.git ``` When your submodule is on the same GitLab server, you should use relative URLs in your `.gitmodules` file. Then you can clone with HTTPS in all your CI/CD jobs. You can also use SSH for all your local checkouts. The above configuration instructs Git to automatically deduce the URL to use when cloning sources. Git uses the same configuration for both HTTPS and SSH. GitLab CI/CD uses HTTPS for cloning your sources, and you can continue to use SSH to clone locally. For submodules not located on the same GitLab server, use the full URL: ```ini [submodule "project-x"] path = project-x url = https://gitserver.com/group/project-x.git ``` ## Use Git submodules in CI/CD jobs To make submodules work correctly in CI/CD jobs: 1. Make sure you use [relative URLs](#configure-the-gitmodules-file) for submodules located in the same GitLab server. 1. You can set the `GIT_SUBMODULE_STRATEGY` variable to either `normal` or `recursive` to tell the runner to [fetch your submodules before the job](runners/configure_runners.md#git-submodule-strategy): ```yaml variables: GIT_SUBMODULE_STRATEGY: recursive ``` If you use the [`CI_JOB_TOKEN`](jobs/ci_job_token.md) to clone a submodule in a pipeline job, the user executing the job must be assigned to a role that has [permission](../user/permissions.md#gitlab-cicd-permissions) to trigger a pipeline in the upstream submodule project. ## Troubleshooting ### Can't find the `.gitmodules` file The `.gitmodules` file might be hard to find because it is usually a hidden file. You can check documentation for your specific OS to learn how to find and display hidden files. If there is no `.gitmodules` file, it's possible the submodule settings are in a [gitconfig](https://www.atlassian.com/git/tutorials/setting-up-a-repository/git-config) file.