GitHub PR to GitLab MR Sync (GitHub Action)

Sync approved GitHub PRs to an internal GitLab codebase as Merge Requests.

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• Workflow Overview
  • Workflow File
  • Inputs
• Steps to Sync a PR
• Project Issues
• Contributing

Workflow Overview

This GitHub Action synchronizes pull requests from GitHub to an internal GitLab instance. When a maintainer approves a PR by adding a label, the action creates a corresponding branch and MR on GitLab.

To use this action you need:

• A workflow file
• Issue/PR labels: PR-Sync-Merge, PR-Sync-Rebase, PR-Sync-Update
• Action secrets

Workflow File

# FILE: .github/workflows/pr_approved.yml

name: Sync approved PRs to internal codebase
on:
  pull_request_target:
    types: [labeled]

jobs:
  sync_prs:
    name: GitHub PR to GitLab MR Sync
    runs-on: ubuntu-latest
    if: contains(fromJSON('["PR-Sync-Merge","PR-Sync-Rebase","PR-Sync-Update"]'), github.event.label.name)
    steps:
      - uses: actions/checkout@v4

      - name: Sync PR to GitLab
        uses: OpenSiFli/sync-pr-to-gitlab@v2
        with:
          github_token: ${{ secrets.GITHUB_TOKEN }}
          gitlab_url: ${{ secrets.GITLAB_URL }}
          gitlab_token: ${{ secrets.GITLAB_TOKEN }}
          git_config_name: ${{ secrets.GIT_CONFIG_NAME }}
          git_config_email: ${{ secrets.GIT_CONFIG_EMAIL }}
          # gitlab_namespace: MY_GROUP  # optional, defaults to GitHub org name

Inputs

Input	Description	Required
github_token	GitHub token for API access	Yes
gitlab_url	GitLab instance host (e.g. gitlab.example.com)	Yes
gitlab_token	GitLab API access token	Yes
git_config_name	Git user.name for rebase commits	Yes
git_config_email	Git user.email for rebase commits	Yes
gitlab_namespace	GitLab namespace/group (defaults to GitHub org name)	No

Steps to Sync a PR

1. Apply one of the following labels:
   • PR-Sync-Merge — create an internal MR from the PR branch head.
   • PR-Sync-Rebase — rebase the PR onto the latest base branch before creating the MR.
   • PR-Sync-Update — force-push new commits to an existing internal branch.
2. The action automatically uses pull_request.head.sha from the label event and validates it against the current PR HEAD before sync.
3. On successful sync, the action updates a managed PR comment with sync metadata (mode, SHA, target branch, trigger user, timestamp). On later updates, the previous managed comment is replaced.

Only contributors with TRIAGE access or higher can apply labels. If new commits are pushed after labeling, the workflow fails by design. Remove/re-apply the label to sync the latest reviewed commit.

Project Issues

If you encounter any issues, feel free to report them in the project's issues or create a Pull Request with your suggestion.

Contributing

If you are interested in contributing to this project, see the Contributing Guide.