[SOLVED] Need to setup a gitlab mirror of a bitbucket repo with only ONE branch exposed

Need to setup a gitlab mirror of a bitbucket repo with only ONE branch exposed

I need to only expose one branch from my bitbucket repo to a new gitlab repo. My students are using the gitlab.com world and I have all my teaching stuff in bitbucket repo's. And I would like to have specific branches for specific classes.

For example:

Bitbucket has the repo APCSA with the branches: master per1 per2 per3 dev

I want to have different repo's setup on gitlab under different gitlab groups.

So under one group I'd like to have them see only:

APCSA:per1 branch (and I'd love to figure out how to mirror this)

I've tried lots of combo's of mirroring but it always mirrors the entire repo, all branches.

Solution

You can create a GitLab CI/CD pipeline to clone, or pull, a single branch. Your pipeline can run on a different branch, in order to avoid conflicts and such.

Using the web ui,

create a new branch called mirror
in Settings, populate CI/CD variables: your upstream, the branch to mirror, and your repo address
create a new file called .gitlab-ci.yml in the mirror branch
- the pipeline will be trigged upon (each) commit, and you'll be able to check if it's working
create a scheduled pipeline to update your repository with the desired frequency

This is my .gitlab-ci.yml to mirror an upstream branch:

job:
    script:
        - git remote show writable || git remote add writable $WRITABLE_URL
        - git checkout $UPSTREAM_BRANCH || git checkout -b $UPSTREAM_BRANCH
        - git pull $UPSTREAM_URL $UPSTREAM_BRANCH
        - git push writable $UPSTREAM_BRANCH
    only:
        - mirror

The variables are:

WRITABLE_URL = destination, ie: 'git@gitlab.myplace.local:upstream/ansible.git'
UPSTREAM_URL = origin, ie: 'https://github.com/ansible/ansible.git'
UPSTREAM_BRANCH = ie: 'stable-2.8'

You will need to use the command line to install gitlab-runner, if you don't have one already. You will also need to create a deploy key (Settings / Repository) in order to allow push to work (or use deploy token, but write access is not available in the free plan for deploy tokens).