Git, you are messing with my flow!

The variety of “flows” for developing using Git makes choosing the right one for your team difficult. When you throw true continuous integration and delivery into that, and add a requirement for immutable build objects, well…. you get a heaping mess.

Infrastructure As Code

Some of my recent work to help one of our teams has been creating a Terraform project and Azure DevOps pipeline based on a colleague’s work in standardizing Kubernetes cluster deployments in AKS. This work will eventually get its own post, but suffice to say that I have a repository which is a mix of Terraform files, Kubernetes manifests, Helm value files, and Azure DevOps pipeline definitions to execute them all.

As I started looking into this, it occurred to me that there really is clear way to manage this project. For example, do I use a single pipeline definition with stages for each environment (dev/stage/production)? This would mean the Git repo would have one and only one branch (main), and each stage would need some checks (manual or automatic) to ensure rollout is controlled.

Alternatively, I can have an Azure Pipeline for each environment. This would mean that each pipeline could trigger on its own branch. However, it also means that no standard Git Flow seems to work well with this.

Code Flows

Quite separately, as the team dove into creating new repositories, the question again came up around branching strategy and subsequent environment strategies for CI/CD. I am a vocal proponent of immutable build objects, but how each team chooses to get there is up to them.

In some MS Teams channel discussion, there are pros and cons to nearly all of our current methods, and the team seems stuck on the best way to build and develop.

The Internet is not helping

Although it is a few years old, Scott Shipp’s War of the Git Flows article highlights the ongoing “flow wars.” One of the problems with Git is the ease with which all of these variations can be implemented. I am not blaming Git, per say, but because it is easy for nearly anyone to suggest a branching strategy, things get muddled quickly.

What to do?

Unfortunately, as with many things in software, there is no one right answer. The branch strategy you use depends on the requirements of not just the team, but the individual repository’s purpose. Additional requirements may come from the desired testing, integration, and deployment process.

With that in mind, I am going to make two slightly radical suggestions

  1. Select a flow that is appropriate for the REPOSITORY, not your team.
  2. Start backwards. Working on identifying the requirements for your deployment process first. Answer questions like this:
  • How will artifacts, once created, be tested?
  • Will artifacts progress through lower environments?
  • Do you have to support old releases?
  • Where (what branch) can a release candidate artifacts come from? Or, what code will ultimately be applied to production?

That last one is vital: defining on paper which branches will either be applied directly to production (in the case of Infrastructure as Code) or generate artifacts that can end up in production (in the case of application builds) will help outline the requirements for the project’s branching strategy.

Once you have identified that, the next step is defining the team’s requirements WITHIN the above. In other words, try not to have the team hammer a square peg into a round hole. They have a branch or two that will generate release code, how they get their code into that branch should be as quick and direct as possible while supporting the collaboration necessary.

What’s next

What’s that mean for me? Well, for the infrastructure project, I am leaning towards a single pipeline, but I need to talk to the Infrastructure team to make sure they agree. As to the software team, I am going to encourage them to apply the process above for each repository in the project.


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