Installation

Prerequisites

Requirement	Why
Python 3.9 or newer	The tool itself
gh	Every GitHub operation goes through it
glab	Every GitLab operation goes through it

Both CLIs must be on PATH and authenticated. The tool never talks to either REST API directly, so if a CLI is missing, the corresponding half simply fails.

Python dependencies (requirements.txt):

• PyYAML — reads config.yaml
• tqdm — progress bar; the code degrades gracefully to no progress bar if it is absent

Install

git clone https://github.com/rennerdo30/gitlab-github-sync.git
cd gitlab-github-sync

python -m venv venv
source venv/bin/activate        # Windows: venv\Scripts\activate
pip install -r requirements.txt

Authenticate the CLIs

Interactively, once per machine:

gh auth login
glab auth login

For a self-managed GitLab instance, point glab at it during login (or set glab config set -g host gitlab.example.com).

Non-interactive environments

In CI or a cron job without a keyring, both CLIs read tokens from the environment:

Variable	Consumed by	Required scope
GH_TOKEN (or GITHUB_TOKEN)	gh	repo
GITLAB_TOKEN	glab	api

No credential is ever read from config.yaml, and none is stored by this project. Export them from your secret manager instead of writing them to a file:

export GH_TOKEN="$(pass show github/pat)"
export GITLAB_TOKEN="$(pass show gitlab/pat)"
python sync.py --dry-run

Verify the setup

gh auth status
glab auth status

cp config.example.yaml config.yaml
python sync.py --dry-run --verbose

A dry run performs no writes. It resolves the repository list, reports which pairs it would touch, and surfaces authentication or permission problems immediately.

Verbose logging and tokens

--verbose enables DEBUG logging, and cli_wrapper.run_command() logs full command lines at that level. Because the GitLab mirror URL embeds a GitHub token, a DEBUG log redirected to a file can end up containing that token. Treat sync.log as a secret, or avoid --verbose when redirecting output. See Mirroring & Scheduling.

A note on GitLab tiers

Code sync uses GitLab’s own mirroring:

• Push mirrors (GitLab → GitHub) work on every tier, including Free.
• Pull mirrors (GitHub → GitLab) require Premium or higher. Without them the run still succeeds — it logs a warning and configures push-only code sync. If you need the GitHub → GitLab direction on a Free tier, generate a GitHub Actions workflow instead; see Mirroring & Scheduling.