Codebase Management for AI Pipelines with GitHub Branches.

Question

Pulumi · Accepted Answer

Managing a codebase for AI pipelines often involves using a version control system like GitHub, where branches are a fundamental concept. Branches enable you to work on features, fixes, or experiments in isolation before integrating them into the main codebase. This is especially important in AI projects, where changes can have significant impacts on the system's behavior.

In the context of AI pipelines, you might have a main branch for stable, production-ready code and several development branches for ongoing work. To ensure that the main branch remains stable, you might set up branch protection rules:

- **GitHub Branch**: Represents a branch within a GitHub repository.
- **GitHub Branch Protection**: Defines protection rules for a branch, like requiring pull request reviews before merging, enforcing code owner reviews, or sign-off with status checks.

Using Pulumi, you can define and manage these GitHub configurations as code. Below is a Pulumi program that demonstrates how to create a new branch and set up branch protection rules with the Pulumi GitHub provider.

```python
import pulumi
import pulumi_github as github

# Substitute these values with your GitHub organization and repository names.
github_organization = "your-organization"
github_repository_name = "your-repo-name"

# Create a new branch from the master branch
new_branch = github.Branch("new-branch",
    branch="new-feature-branch",
    repository=github_repository_name,
    source_branch="master",
)

# Set up branch protection rules for the main branch
branch_protection = github.BranchProtection("main-branch-protection",
    pattern="main", # This is the name of the branch you want to protect.
    repository=github_repository_name,
    enforce_admins=False,
    allows_deletions=False,
    required_pull_request_reviews=github.BranchProtectionRequiredPullRequestReviewsArgs(
        dismiss_stale_reviews=True,
        require_code_owner_reviews=True,
        required_approving_review_count=2,
    ),
    required_status_checks=github.BranchProtectionRequiredStatusChecksArgs(
        strict=True,
        contexts=[
            "continuous-integration/travis-ci",  # Substitute with your CI context
        ],
    ),
)

# Export the URLs for the new branch
pulumi.export('new_branch_name', new_branch.branch)
pulumi.export('new_branch_ref', new_branch.ref)
```

In this program:
- We use the `github.Branch` resource to create a new branch called `new-feature-branch` from the `master` branch.
- Then, we apply protection rules to the `main` branch with the `github.BranchProtection` resource. The protection rules we've implemented enforce that:
  - Admins are not exempt from the branch protection rules (`enforce_admins=False`).
  - Deletions of the protected branch are not allowed (`allows_deletions=False`).
  - Pull requests must have at least two reviews before merging, which includes reviews from code owners (`required_approving_review_count=2` and `require_code_owner_reviews=True`).
  - Reviews must not be dismissed when new commits are pushed (`dismiss_stale_reviews=True`).
  - We enforce status checks before merging, such as continuous integration (CI) tests, which in this case uses Travis CI.

These configurations can help maintain the integrity of the main branch, which is key for a stable AI pipeline in production. It ensures that all code changes are carefully reviewed and tested before integration, reducing the risk of introducing errors or regressions.

Remember to replace the placeholder values `your-organization` and `your-repo-name` with your actual GitHub organization and repository names. Also, adjust the `continuous-integration/travis-ci` context to match the CI tool you're using.

Before running this program:

- Ensure you have the [Pulumi CLI installed](https://www.pulumi.com/docs/get-started/install/).
- Configure Pulumi to [use your GitHub token](https://www.pulumi.com/registry/packages/github/installation-configuration/), so it has permissions to manage resources on your behalf.

To run the program:

1. [Install Python](https://www.python.org/downloads/) if not already installed and set up a virtual environment:
   ```sh
   python3 -m venv venv
   source venv/bin/activate
   ```
2. Install the required Pulumi packages:
   ```sh
   pip install pulumi pulumi_github
   ```
3. Save your Pulumi program in a file (e.g., `__main__.py`).
4. Run `pulumi up` to preview and deploy your changes. Follow the prompts by the CLI to select your desired action.

After running the program, check your GitHub repository branch settings to see the new branch and applied protection rules.