Securing AI Codebases with GitHub Branch Protection Rules

Question

Pulumi · Accepted Answer

To secure AI codebases with GitHub Branch Protection Rules using Pulumi, we'll define a set of rules for a repository's branches that ensure certain criteria are met before code can be merged. Branch protection rules can include requirements for pull request reviews, status checks, commit signatures, and more.

In this program, we will use the `github.BranchProtectionV3` resource from the Pulumi GitHub provider. This will allow us to create rules that:

- Require pull request reviews before merging.
- Require status checks to pass before merging.
- Enforce restrictions on who can push to the branch.
- Require signed commits.
- Require that conversations on pull requests are resolved before merging.

Here's a detailed breakdown of the program we are going to write:

1. **Importing Pulumi Packages**: We need to import the necessary Pulumi GitHub package to interact with GitHub.
2. **Creating a Branch Protection Rule**: Using `github.BranchProtectionV3`, we will define the branch protection rule for a branch in our repository.

Let's dive into the code.

```python
import pulumi
import pulumi_github as github

# Replace these variables with your desired settings.
repo_name = "your-ai-codebase-repo"  # Your GitHub repository name.
branch_name = "main"  # The branch you want to protect.

# Define a branch protection rule.
branch_protection = github.BranchProtectionV3("branch-protection",
    branch=branch_name,
    repository=repo_name,
    enforce_admins=True,
    require_signed_commits=True,
    required_status_checks=github.BranchProtectionV3RequiredStatusChecksArgs(
        checks=[
            "ci/build",  # Example of a required status check.
        ],
        strict=True,
    ),
    required_pull_request_reviews=github.BranchProtectionV3RequiredPullRequestReviewsArgs(
        require_code_owner_reviews=True,
        required_approving_review_count=1,
        dismissal_teams=["security-team"],  # Example of a team that can dismiss pull request reviews.
        dismiss_stale_reviews=True,
    ),
    restrictions=github.BranchProtectionV3RestrictionsArgs(
        users=["trusted-contributor"],  # Specify users who can push to the branch.
        teams=["core-team"],  # Specify teams allowed to push to the branch.
    ),
)

# Export the ID of the branch protection rule.
pulumi.export("branch_protection_id", branch_protection.id)
```

In the above program:

- We start by importing `pulumi` and `pulumi_github`, which contain the necessary classes and methods to interact with GitHub using Pulumi.
- We create a `github.BranchProtectionV3` resource named `branch-protection`.
- We specify the branch and repository that we want to apply the protection rules to.
- We turn on enforcement for admins with `enforce_admins=True`, ensuring that even repository administrators are subject to the branch protection rules.
- We require signed commits for the protected branch with `require_signed_commits=True`.
- We define required status checks that need to pass before code can be merged.
- We set up rules for pull request reviews, including requiring reviews from code owners, specifying the number of required approving reviews, and defining which teams can dismiss reviews.
- We specify restrictions on who can push to the branch, which we can use to limit push access to trusted contributors and teams.

When applied, this program will enforce these branch protection rules on the specified repository and branch, helping to secure your AI codebase from unauthorized or accidental changes that don't meet defined criteria.

Make sure to customize the values of `repo_name`, `branch_name`, and other placeholders such as `"ci/build"`, `"security-team"`, `"trusted-contributor"`, and `"core-team"` with the actual names relevant to your GitHub repository and organizational structure.

By using Pulumi to automate the creation of such rules, you achieve a more consistent and repeatable process, reducing the chance of human error and helping to maintain a high security standard for your codebase.