I'd like Gitlab CI to fetch source code of another project. Is there a better way than adding a read-only deploy key and setting it up in .gitlab-ci.yml?
You can also use GIT SUBMODULES within your project A to refer to project B and then add
GIT_SUBMODULE_STRATEGY: recursive
to the gitlab-ci.yml file in project A.
This also enables you to specifically include a specific branch or commit from your subproject.
来源：https://stackoverflow.com/questions/44444616/git-clone-project2-in-gitlab-ci-yml