Execution Plan: Resolving PRs 1477 and 1475

Background

• PRs: 1477 (Postgres) and 1475 (MySQL)
• Goal: Update the app.yaml files for the GAE Flex Rails 7 tutorials to use modern Ruby versions (e.g., 3.2 or 3.3) on ubuntu22, fixing the "end of support" error described in Issue Rails7 deployment to GAE Flex fails: Your runtime version for ruby is past End of Support. #1476.
• Current Proposed Fix in PRs: Added runtime_config: operating_system: "ubuntu22" to app.yaml.

Current Roadblocks / Comments

1. CI Pipeline Failures: glasnt identified that the oldest tested Ruby version is failing due to issues with built-in Gemfile config versions. They suggested updating the repository's oldest supported testing ruby version.
2. Deployment Errors: bipashant tested the PR and still received an error: runtime ruby32 is not selectable with operating system ubuntu22. This suggests the current patch in the PR is incomplete or incorrectly specifies the GAE Flex environment for newer Rubies.

Recommended Execution Steps

Step 1: Fix CI Matrix (Address glasnt's feedback)

• Investigate the central CI configurations (likely in .kokoro/ or .github/workflows/).
• Update the Ruby version matrix to drop unsupported EOL Rubies (like 2.6/2.7/3.0) and include modern versions (3.2 and 3.3).
• Update the oldest tested Ruby to at least 3.1 or 3.2.

Step 2: Validate GAE Flex Configuration (Address bipashant's feedback)

• Research the exact app.yaml syntax required to run Ruby 3.2+ on ubuntu22 in GAE Flex.
• It likely requires either:
  1. Adding a .ruby-version file to the directories specifying 3.2.3 (or similar) AND keeping the operating_system: "ubuntu22" in app.yaml.
  2. Specifying runtime_version under runtime_config within app.yaml.
• Deploy locally using gcloud app deploy (or dry-run) to a test project to ensure the INVALID_ARGUMENT error resolves.

Step 3: Implement Changes in PRs

• For both appengine/rails-cloudsql-postgres and appengine/rails-cloudsql-mysql:
  • Adjust app.yaml based on the successful syntax from Step 2.
  • Adding .ruby-version if necessary.
  • Update Gemfile/Gemfile.lock to reflect changes if bounded by bundler requirements.
• Commit these changes directly to the respective branches for PR 1477 (palladius-patch-2) and PR 1475 (palladius-patch-1), or create a new consolidated PR linking both.

Step 4: Finalize

• Confirm CI passes after adjusting the ruby matrix.
• Reply to reviewers glasnt and bipashant, requesting re-review.
• Merge the PRs.