Bitbucket Cloud importer developer documentation - Gitlabhq

Prerequisites

You must be authenticated with Bitbucket:

If you use GitLab Development Kit (GDK), see Set up Bitbucket authentication on GDK.
Otherwise, see Bitbucket OmniAuth provider instructions.

Code structure

The importer's codebase is broken up into the following directories:

lib/gitlab/bitbucket_import: this directory contains most of the code such as the classes used for importing resources.
app/workers/gitlab/bitbucket_import: this directory contains the Sidekiq workers.

Architecture overview

When a Bitbucket Cloud project is imported, work is divided into separate stages, with each stage consisting of a set of Sidekiq jobs that are executed. Between every stage, a job is scheduled that periodically checks if all work of the current stage is completed, advancing the import process to the next stage when this is the case. The worker handling this is called Gitlab::BitbucketImport::AdvanceStageWorker.

Stages

1. Stage::ImportRepositoryWorker

This worker imports the repository, wiki and labels, scheduling the next stage when done.

2. Stage::ImportUsersWorker

This worker imports members of the source Bitbucket Cloud workspace.

3. Stage::ImportPullRequestsWorker

This worker imports all pull requests. For every pull request, a job for the Gitlab::BitbucketImport::ImportPullRequestWorker worker is scheduled.

4. Stage::ImportPullRequestsNotesWorker

This worker imports notes (comments) for all merge requests.

For every merge request, a job for the Gitlab::BitbucketImport::ImportPullRequestNotesWorker worker is scheduled which imports all notes for the merge request.

5. Stage::ImportIssuesWorker

This worker imports all issues. For every issue, a job for the Gitlab::BitbucketImport::ImportIssueWorker worker is scheduled.

6. Stage::ImportIssuesNotesWorker

This worker imports notes (comments) for all issues.

For every issue, a job for the Gitlab::BitbucketImport::ImportIssueNotesWorker worker is scheduled which imports all notes for the issue.

7. Stage::FinishImportWorker

This worker completes the import process by performing some housekeeping such as marking the import as completed.

Backoff and retry

In order to handle rate limiting, requests are wrapped with Bitbucket::ExponentialBackoff. This wrapper catches rate limit errors and retries after a delay up to three times.

Set up Bitbucket authentication on GDK

To set up Bitbucket authentication on GDK:

Follow the documentation up to step 9 to create Bitbucket OAuth credentials.

Add the credentials to config/gitlab.yml:

yaml

# config/gitlab.yml

development:
  <<: *base
  omniauth:
    providers:
    - { name: 'bitbucket',
        app_id: '...',
        app_secret: '...' }

Run gdk restart.
Sign in to your GDK, go to <gdk-url>/-/profile/account, and connect Bitbucket.