How To Migrate From GitLab to GitHub?

Migrating from GitLab to GitHub can be a strategic move for organizations looking to use GitHub’s extensive ecosystem, advanced CI/CD capabilities, or better integration with their existing workflows.

Whether you're moving a single repository or an entire organization, this guide will help you navigate the migration process smoothly.

Why Migrate from GitLab to GitHub?

Organizations may choose to migrate from GitLab to GitHub for various reasons, including:

• Better Integration: GitHub offers a vast ecosystem of integrations, including native CI/CD with GitHub Actions, which can streamline workflows.
• Developer Community: GitHub's extensive community and collaboration features make it a popular choice for open-source projects.
• Advanced Features: GitHub provides advanced features like Codespaces for cloud-based development environments and Copilot for AI-assisted coding.

Difference Between GitLab and GitHub

• CI/CD: While GitLab offers integrated CI/CD tools, GitHub provides GitHub Actions, which allows for more complex workflows.
• Project Management: GitLab includes built-in project management tools, whereas GitHub relies on integrations like GitHub Projects and other third-party apps.
• User Interface and Experience: GitHub’s interface is often seen as more user-friendly, making it easier for new users to adapt.

Pre-Migration Checklist

Evaluate Your Current Setup

Before migrating, review your current GitLab setup:

• Identify active repositories and projects.
• List existing CI/CD pipelines, integrations, and custom configurations.
• Check user roles, permissions, and access levels.

Backup Your GitLab Data

Create backups of your GitLab data to prevent any loss during the migration:

• Use GitLab’s built-in backup tools to export repositories, issues, merge requests, and more.
• Store backups securely in a cloud storage solution or an external drive.

Identify Repositories to Migrate

Decide whether you’ll migrate all repositories or only specific ones:

• Consider starting with a few critical repositories as a pilot before migrating everything.
• Document any deprecated or inactive repositories to decide if they should be archived rather than migrated.

Check for Compatibility Issues

Review potential compatibility issues between GitLab and GitHub:

• Identify GitLab-specific features like CI/CD configurations that might not translate directly to GitHub Actions.
• Note any differences in project settings or permissions that could impact workflows.

Migration Methods

1. Using GitHub’s Import Tool

GitHub provides an Import Tool that simplifies the migration process:

• This tool allows you to import repositories from GitLab directly into GitHub.
• It's user-friendly and suitable for simple migrations.

2. Manual Migration via Command Line

For more control, consider a manual migration using the command line:

• Clone the GitLab repository locally.
• Push the repository to GitHub using Git commands.

3. Automated Migration with GitHub CLI

GitHub CLI offers commands for automating parts of the migration process:

• Scripts can be created to handle repetitive tasks like repository creation, issues importing, and more.

4. Using Third-Party Tools

Several third-party tools can assist in migrating complex setups:

• Tools like gitlab2github provide scripts and utilities to handle large-scale migrations, including CI/CD configurations and user permissions.

Step-by-Step Migration Process

Step 1: Preparing GitHub Account

• Set Up GitHub Organization: Create or configure a GitHub organization to receive the repositories.
• Permissions and Access: Set up necessary permissions for team members.

Step 2: Exporting Data from GitLab

• Export Repositories: Use GitLab’s export functionality to export repositories as .tar.gz files.
• Export Issues and Merge Requests: Ensure that all relevant project data, such as issues and merge requests, are included in the export.

Step 3: Importing Repositories to GitHub

• Using GitHub Importer: Navigate to GitHub’s Importer tool and select GitLab as the source.
• Follow Prompts: Enter GitLab credentials and select repositories to import.

Step 4: Verifying the Migration

• Check Repositories: Verify that all repositories are present and accessible.
• Review Issues and Pull Requests: Ensure that issues, pull requests, and other project data have been correctly imported.

Step 5: Configuring GitHub Workflows

• Set Up GitHub Actions: Replace GitLab CI/CD pipelines with GitHub Actions workflows.
• Recreate Environment Variables: Ensure that all necessary environment variables and secrets are configured in GitHub.

Step 6: Updating CI/CD Pipelines

• Translate Pipelines: Convert GitLab CI/CD configurations into GitHub Actions workflows.
• Test Pipelines: Run tests to validate that the new workflows function as expected.

Step 7: Testing and Validation

• Test Functionality: Perform end-to-end testing of the repositories, CI/CD pipelines, and integrations.
• Fix Issues: Address any issues found during testing, such as broken links or missing configurations.

Post-Migration Tasks

Reconfigure Webhooks and Integrations

• Update Webhooks: Reconfigure any webhooks pointing to GitLab to now point to GitHub.
• Reintegrate Tools: Ensure integrations like Slack notifications, project management tools, and others are reconnected to GitHub.

Update Documentation and Scripts

• Review Documentation: Update any internal documentation that references GitLab.
• Adjust Scripts: Modify scripts that interact with GitLab APIs to now use GitHub APIs.

Notify Teams and Stakeholders

• Communicate Changes: Inform your team and stakeholders of the migration, including any new workflows or processes.
• Provide Training: Offer training sessions or resources to help users adapt to GitHub.

Common Issues and Troubleshooting

Handling Large Repositories

• Optimize Repositories: Consider breaking large repositories into smaller, more manageable components.
• Use Git LFS: For repositories with large files, consider using Git Large File Storage (LFS).

Resolving Permissions and Access Issues

• Review Access Levels: Ensure that user permissions are correctly set up in GitHub.
• Map GitLab Roles to GitHub: Map GitLab roles (e.g., Maintainer, Developer) to GitHub’s role system.

Migrating CI/CD Configurations

• Translate CI/CD Pipelines: Convert GitLab CI/CD configurations into GitHub Actions workflows.
• Test Pipelines: Thoroughly test new CI/CD pipelines to ensure they work as intended.

Dealing with GitLab-specific Features

• Replace GitLab Pages: If using GitLab Pages for static site hosting, consider GitHub Pages as an alternative.
• Work with GitHub Apps: Identify GitHub Apps that can replicate or replace GitLab-specific features.