build: enforce conventional commit message formatting

1. Add a git commit-msg hook to validate commit messages as they are made
2. Add a GitHub workflow to validate that all commits in a PR conform to conventional commits

.commitlintrc.yml

@@ -0,0 +1,16 @@
+---
+extends: '@commitlint/config-conventional'
+
+rules:
+  # See: https://commitlint.js.org/reference/rules.html
+  #
+  # Rules are made up by a name and a configuration array. The configuration array contains:
+  #
+  # * Severity [0..2]: 0 disable rule, 1 warning if violated, or 2 error if violated
+  # * Applicability [always|never]: never inverts the rule
+  # * Value: value to use for this rule
+  #
+  # Run `npx commitlint --print-config` to see the current setting for all rules.
+  #
+  body-leading-blank:    [2, 'always']
+  footer-leading-blank:  [2, 'always']

.github/workflows/enforce_conventional_commits.yml

@@ -0,0 +1,21 @@
+name: Conventional Commits
+
+on:
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  commit-lint:
+    name: Verify Conventional Commits
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with: { fetch-depth: 0 }
+
+      - name: Check Commit Messages
+        uses: wagoid/commitlint-github-action@v6
+        with: { configFile: .commitlintrc.yml }

.gitignore

@@ -14,3 +14,6 @@
 /rspec-report.xml
 /rubocop-report.json
 /sig
+
+node_modules
+package-lock.json

.husky/commit-msg

@@ -0,0 +1 @@
+npx --no-install commitlint --edit "$1"

README.md

@@ -6,6 +6,8 @@
 [![Build Status](https://github.com/main-branch/discovery_v1/actions/workflows/continuous_integration.yml/badge.svg)](https://github.com/main-branch/discovery_v1/actions/workflows/continuous_integration.yml)
 [![Maintainability](https://api.codeclimate.com/v1/badges/aeebc016487c5cad881e/maintainability)](https://codeclimate.com/github/main-branch/discovery_v1/maintainability)
 [![Test Coverage](https://api.codeclimate.com/v1/badges/aeebc016487c5cad881e/test_coverage)](https://codeclimate.com/github/main-branch/discovery_v1/test_coverage)
+[![Conventional
+Commits](https://img.shields.io/badge/Conventional%20Commits-1.0.0-%23FE5196?logo=conventionalcommits&logoColor=white)](https://conventionalcommits.org)
 [![Slack](https://img.shields.io/badge/slack-main--branch/discovery__v1-yellow.svg?logo=slack)](https://main-branch.slack.com/archives/C07MT5MG7V1)
 
 Unofficial helpers and extensions for the Google Discovery V1 API
@@ -33,6 +35,8 @@ Gems in the Google API helper, extensions, and examples series:
     * [RestDescription Extensions](#restdescription-extensions)
 * [Development](#development)
 * [Contributing](#contributing)
+  * [Commit message guidelines](#commit-message-guidelines)
+  * [Pull request guidelines](#pull-request-guidelines)
 * [License](#license)
 * [Code of Conduct](#code-of-conduct)
 
@@ -201,6 +205,31 @@ To install this gem onto your local machine, run `bundle exec rake install`. To
 
 Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/discovery_v1. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [code of conduct](https://github.com/[USERNAME]/discovery_v1/blob/main/CODE_OF_CONDUCT.md).
 
+### Commit message guidelines
+
+All commit messages must follow the [Conventional Commits
+standard](https://www.conventionalcommits.org/en/v1.0.0/). This helps us maintain a
+clear and structured commit history, automate versioning, and generate changelogs
+effectively.
+
+To ensure compliance, this project includes:
+
+* A git commit-msg hook that validates your commit messages before they are accepted.
+
+  To activate the hook, you must have node installed and run `npm install`.
+
+* A GitHub Actions workflow that will enforce the Conventional Commit standard as
+  part of the continuous integration pipeline.
+
+  Any commit message that does not conform to the Conventional Commits standard will
+  cause the workflow to fail and not allow the PR to be merged.
+
+### Pull request guidelines
+
+All pull requests must be merged using rebase merges. This ensures that commit
+messages from the feature branch are preserved in the release branch, keeping the
+history clean and meaningful.
+
 ## License
 
 The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).

bin/setup

@@ -1,8 +1,15 @@
 #!/usr/bin/env bash
+
 set -euo pipefail
 IFS=$'\n\t'
-set -vx
+
+# set -vx
 
 bundle install
 
-# Do any other automated setup that you need to do here
+if [ -x "$(command -v npm)" ]; then
+  npm install
+else
+  echo "npm is not installed"
+  echo "Install npm then re-run this script to enable the conventional commit git hook."
+fi

discovery_v1.gemspec

@@ -35,7 +35,7 @@ Gem::Specification.new do |spec|
   spec.require_paths = ['lib']
 
   spec.add_development_dependency 'bundler-audit', '~> 0.9'
-  spec.add_development_dependency 'create_github_release', '~> 1.5'
+  spec.add_development_dependency 'create_github_release', '~> 2.1'
   spec.add_development_dependency 'main_branch_shared_rubocop_config', '~> 0.1'
   spec.add_development_dependency 'rake', '~> 13.2'
   spec.add_development_dependency 'rspec', '~> 3.13'

package.json

@@ -0,0 +1,11 @@
+{
+  "devDependencies": {
+    "@commitlint/cli": "^19.5.0",
+    "@commitlint/config-conventional": "^19.5.0",
+    "husky": "^9.1.0"
+  },
+  "scripts": {
+    "postinstall": "husky",
+    "prepare": "husky"
+  }
+}