Import your project from GitHub to GitLab

You can import your GitHub repositories:

  • From either GitHub.com or GitHub Enterprise.
  • To either GitLab.com or a self-managed GitLab instance.

This process does not migrate or import any types of groups or organizations from GitHub to GitLab.

The namespace is a user or group in GitLab, such as gitlab.com/sidney-jones or gitlab.com/customer-success. You can use bulk actions in the rails console to move projects to different namespaces.

If you are importing to a self-managed GitLab instance, you can use the GitHub Rake task instead. This allows you to import projects without the constraints of a Sidekiq worker.

If you are importing from GitHub Enterprise to a self-managed GitLab instance:

If you are importing from GitHub.com to a self-managed GitLab instance:

  • Setting up GitHub integration is not required.
  • You can use the Import API.

When importing projects:

  • If a user referenced in the project is not found in the GitLab database, the project creator is set as the author and assignee. The project creator is usually the user that initiated the import process. A note on the issue mentioning the original GitHub author is added.
  • The importer creates any new namespaces (or groups) if they do not exist, or, if the namespace is taken, the repository is imported under the namespace of the user who initiated the import process. The namespace or repository name can also be edited, with the proper permissions.
  • The importer also imports branches on forks of projects related to open pull requests. These branches are imported with a naming scheme similar to GH-SHA-username/pull-request-number/fork-name/branch. This may lead to a discrepancy in branches compared to those of the GitHub repository.

For additional technical details, refer to the GitHub Importer developer documentation.

For an overview of the import process, see the video Migrating from GitHub to GitLab.

Prerequisites

When issues and pull requests are being imported, the importer attempts to find their GitHub authors and assignees in the database of the GitLab instance. Pull requests are called merge requests in GitLab.

For this association to succeed, each GitHub author and assignee in the repository must meet one of the following conditions prior to the import:

  • Have previously logged in to a GitLab account using the GitHub icon.
  • Have a GitHub account with a public-facing email address that matches their GitLab account’s email address.

GitLab content imports that use GitHub accounts require that the GitHub public-facing email address is populated. This means all comments and contributions are properly mapped to the same user in GitLab. GitHub Enterprise does not require this field to be populated so you may have to add it on existing accounts.

Import your GitHub repository into GitLab

Use the GitHub integration

Before you begin, ensure that any GitHub users who you want to map to GitLab users have either:

  • A GitLab account that has logged in using the GitHub icon.
  • A GitLab account with an email address that matches the publicly visible email address in the profile of the GitHub user

If you are importing to GitLab.com, you can alternatively import GitHub repositories using a personal access token. We do not recommend this method, as it does not associate all user activity (such as issues and pull requests) with matching GitLab users.

User-matching attempts occur in that order, and if a user is not identified either way, the activity is associated with the user account that is performing the import.

note
If you are using a self-managed GitLab instance or if you are importing from GitHub Enterprise, this process requires that you have configured GitHub integration.
  1. From the top navigation bar, select + and select New project.
  2. Select the Import project tab and then select GitHub.
  3. Select the first button to List your GitHub repositories. You are redirected to a page on GitHub to authorize the GitLab application.
  4. Select Authorize GitlabHQ. You are redirected back to the GitLab Import page and all of your GitHub repositories are listed.
  5. Continue on to selecting which repositories to import.

Use a GitHub token

note
Using a personal access token to import projects is not recommended. If you are a GitLab.com user, you can use a personal access token to import your project from GitHub, but this method cannot associate all user activity (such as issues and pull requests) with matching GitLab users. If you are an administrator of a self-managed GitLab instance or if you are importing from GitHub Enterprise, you cannot use a personal access token. The GitHub integration method (above) is recommended for all users.

If you are not using the GitHub integration, you can still perform an authorization with GitHub to grant GitLab access your repositories:

  1. Go to https://github.com/settings/tokens/new
  2. Enter a token description.
  3. Select the repository scope.
  4. Select Generate token.
  5. Copy the token hash.
  6. Go back to GitLab and provide the token to the GitHub importer.
  7. Hit the List Your GitHub Repositories button and wait while GitLab reads your repositories’ information. Once done, you are taken to the importer page to select the repositories to import.

To use a newer personal access token in imports after previously performing these steps, sign out of your GitLab account and sign in again, or revoke the older personal access token in GitHub.

Select which repositories to import

After you have authorized access to your GitHub repositories, you are redirected to the GitHub importer page and your GitHub repositories are listed.

  1. By default, the proposed repository namespaces match the names as they exist in GitHub, but based on your permissions, you can choose to edit these names before you proceed to import any of them.
  2. Select the Import button next to any number of repositories, or select Import all repositories. Additionally, you can filter projects by name. If filter is applied, Import all repositories only imports matched repositories.
  3. The Status column shows the import status of each repository. You can choose to leave the page open and it will update in real-time or you can return to it later.
  4. Once a repository has been imported, select its GitLab path to open its GitLab URL.

GitHub importer page

Mirror a repository and share pipeline status

Depending on your GitLab tier, repository mirroring can be set up to keep your imported repository in sync with its GitHub copy.

Additionally, you can configure GitLab to send pipeline status updates back to GitHub with the GitHub Project Integration.

If you import your project using CI/CD for external repository, then both of the above are automatically configured.

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Mirroring does not sync any new or updated pull requests from your GitHub project.

Improve the speed of imports on self-managed instances

Administrator access on the GitLab server is required for this process.

For large projects it may take a while to import all data. To reduce the time necessary, you can increase the number of Sidekiq workers that process the following queues:

  • github_importer
  • github_importer_advance_stage

For an optimal experience, it’s recommended having at least 4 Sidekiq processes (each running a number of threads equal to the number of CPU cores) that only process these queues. It’s also recommended that these processes run on separate servers. For 4 servers with 8 cores this means you can import up to 32 objects (for example, issues) in parallel.

Reducing the time spent in cloning a repository can be done by increasing network throughput, CPU capacity, and disk performance (by using high performance SSDs, for example) of the disks that store the Git repositories (for your GitLab instance). Increasing the number of Sidekiq workers does not reduce the time spent cloning repositories.

Imported data

The following items of a project are imported:

References to pull requests and issues are preserved. Each imported repository maintains visibility level unless that visibility level is restricted, in which case it defaults to the default project visibility.

Alternative way to import notes and diff notes

When GitHub Importer runs on extremely large projects not all notes & diff notes can be imported due to GitHub API issues_comments & pull_requests_comments endpoints limitation. Not all pages can be fetched due to the following error coming from GitHub API: In order to keep the API fast for everyone, pagination is limited for this resource. Check the rel=last link relation in the Link response header to see how far back you can traverse..

An alternative approach for importing notes and diff notes is available behind a feature flag.

Instead of using issues_comments and pull_requests_comments, use individual resources issue_comments and pull_request_comments instead to pull notes from one object at a time. This allows us to carry over any missing comments, however it increases the number of network requests required to perform the import, which means its execution takes a longer time.

To use the alternative way of importing notes, the github_importer_single_endpoint_notes_import feature flag must be enabled on the group project is being imported into.

Start a Rails console.

group = Group.find_by_full_path('my/group/fullpath')

# Enable
Feature.enable(:github_importer_single_endpoint_notes_import, group)

# Disable
Feature.disable(:github_importer_single_endpoint_notes_import, group)

Reduce GitHub API request objects per page

Some GitHub API endpoints may return a 500 or 502 error for project imports from large repositories. To reduce the chance of such errors, you can enable the feature flag github_importer_lower_per_page_limit in the group project importing the data. This reduces the page size from 100 to 50.

To enable this feature flag, start a Rails console and run the following enable command:

group = Group.find_by_full_path('my/group/fullpath')

# Enable
Feature.enable(:github_importer_lower_per_page_limit, group)

To disable the feature, run this command:

# Disable
Feature.disable(:github_importer_lower_per_page_limit, group)

Automate group and project import

For information on automating user, group, and project import API calls, see Automate group and project import.