Migration to Gitlab

Alright, buckle up, fellow code wranglers! We recently embarked on a significant journey here at [Your Website/Company Name]: migrating our entire code repository from GitHub to GitLab. It was a decision we didn’t take lightly, and now that the dust has settled (mostly!), we wanted to share our experience, the good, the… well, less good but ultimately manageable.

For a while now, GitHub has been our trusty companion, housing our precious code and facilitating collaboration. However, as our team and projects grew, we started to look at other options that might better align with our evolving needs. We weighed several factors, and ultimately, GitLab emerged as the platform that resonated most with our vision.

This post isn’t about declaring one platform “better” than the other. Both are fantastic tools. Instead, we want to pull back the curtain on our specific reasons, the steps we took, the bumps we encountered, and the benefits we’re already seeing on the other side. Hopefully, our experience will provide valuable insights if you’re also considering a similar migration.

Our decision to switch wasn’t driven by a single factor, but rather a confluence of compelling reasons:

The All-in-One DevOps Platform: GitLab’s tightly integrated suite of features was a major draw. We were particularly excited about the potential of its robust CI/CD pipeline to streamline our build, test, and deployment processes. Having issue tracking, merge requests, and a wiki seamlessly connected within the same platform promised to reduce context switching and boost efficiency. Unlimited Private Repositories for Free: As our team expanded and side projects multiplied, the cost of managing private repositories became a consideration. GitLab’s generous offering of unlimited private repositories for free was a significant advantage for our growing needs. Self-Hosting Potential and Control: While we opted for GitLab’s SaaS offering for now, the option for self-hosting down the line provides a level of control and flexibility that aligns with our long-term infrastructure strategy. This open-source foundation resonated with our commitment to understanding and managing our tools deeply. Integrated Container Registry: GitLab’s built-in container registry simplified our Docker workflow, offering a convenient and secure place to store and manage our container images, directly linked to our projects. While GitHub Actions is undoubtedly powerful, we found GitLab CI/CD’s configuration, with its .gitlab-ci.yml file, felt more intuitive for our specific deployment scenarios. This isn’t to say one is superior, but for our team’s existing skillset and preferences, GitLab felt like a more natural fit.

Embarking on a migration of this scale requires careful planning and execution. Here’s a breakdown of the steps we took:

The Grand Strategy Session: We started by thoroughly assessing the size and complexity of our GitHub repositories. We identified key dependencies, notified our team well in advance, and established a timeline for the migration. Communication was key to ensuring everyone was on board and understood the process. Choosing Our Migration Path: Mirroring with a Twist: We decided to initially mirror our GitHub repositories to GitLab. This allowed us to keep GitHub as the primary source of truth during the initial phase, minimizing disruption to our ongoing work. GitLab’s import functionality made this relatively straightforward. We simply provided the repository URLs and our GitHub credentials. The Great Import: Once we felt comfortable and had a good understanding of GitLab’s environment, we transitioned from mirroring to a direct import for most repositories. This essentially created independent copies in GitLab. For a few particularly active repositories, we maintained mirroring for a short period longer to ensure a smooth cutover. Tackling the Trickiest Part: Issues and Merge Requests: This was arguably the most challenging aspect. While GitLab offers import functionality, migrating historical issues and pull/merge requests perfectly can be tricky. We explored a few third-party tools, but ultimately opted for a hybrid approach. For critical active issues and merge requests, we manually recreated them in GitLab, linking back to the original GitHub entries for context. For older, closed issues, we decided to keep them in GitHub for historical reference, acknowledging that a perfect migration wasn’t feasible without significant effort. Wrangling the Wiki: Migrating our GitHub Wiki pages was a relatively smooth process using Git clone and push. GitLab’s Wiki functionality is similar enough that the transition was straightforward. Updating the Webhooks and Integrations: This was a crucial step to ensure our automated workflows continued to function seamlessly. We meticulously reviewed all our webhooks, CI/CD pipelines in other tools, and third-party integrations, updating their URLs and credentials to point to the new GitLab repositories. This required careful testing to avoid breaking our deployment and notification systems. DNS and Remote Adjustments: We updated our internal documentation and communicated clearly to the team about the new Git URLs. Each developer had to update their local Git remotes to point to the GitLab repositories. This required clear instructions and a bit of hand-holding to ensure everyone made the change correctly. Challenges and Lessons Learned (The Bumps in the Road):

No major migration goes perfectly, and we certainly learned a few things along the way:

Issue and Merge Request Fidelity: As mentioned, achieving a perfect migration of historical issues and merge requests is a significant challenge. We had to make a pragmatic decision about what level of detail to preserve. CI/CD Script Adjustments: While GitLab CI/CD is powerful, we did need to adapt some of our existing GitHub Actions workflows to align with GitLab’s syntax and structure. This required some learning and testing. Team Familiarization: While the core Git concepts remain the same, the GitLab UI and some specific features required a period of familiarization for the team. We invested in internal documentation and knowledge-sharing sessions to help everyone get up to speed. The Importance of Thorough Testing: We cannot stress enough the importance of rigorous testing after each stage of the migration. We created test repositories and ran through our key workflows to identify and resolve any issues before they impacted our main projects. Life After Migration: The Benefits We’ve Seen (The Smooth Sailing Part):

Despite the challenges, we’re already seeing significant benefits from our move to GitLab:

Streamlined CI/CD: The integrated CI/CD pipeline has indeed simplified our deployment process. The .gitlab-ci.yml configuration feels intuitive, and having it directly within the repository has improved visibility and collaboration on our deployment workflows. Improved Collaboration: The tight integration of issues, merge requests, and code within GitLab fosters a more collaborative environment. Discussions are more contextual, and navigating between related items is much smoother. Better Organization: Unlimited private repositories have allowed us to better structure our internal projects and experiments without worrying about cost implications. Enhanced Control and Visibility: Even with the SaaS offering, GitLab provides a greater sense of control over our development lifecycle. The detailed audit logs and granular permission settings offer enhanced visibility and security. Conclusion: A Journey Worth Taking

Migrating our code repository from GitHub to GitLab was a significant undertaking, but one that we believe will ultimately benefit our team and our development processes in the long run. While we encountered a few bumps along the way, the advantages of GitLab’s integrated platform, flexible repository options, and robust CI/CD capabilities are already proving their worth.

If you’re considering a similar migration, we hope our experience provides some valuable insights. Remember to plan thoroughly, communicate clearly with your team, and be prepared for a few unexpected twists and turns. The destination, however, can be well worth the journey.

Have you gone through a similar migration? What were your experiences? Share your thoughts and questions in the comments below! We’d love to hear from you.