How to setup Conventional Commits in JavaScript project

Conventional Commits is a specification for adding human and machine readable meaning to commit messages. It provides an easy set of rules for creating an explicit commit history, which makes it easier to write automated tools on top of.

Commits History

Basic Structure

The commit message should be structured as follows:

<type>[optional scope]: <description>

[optional body]

[optional footer(s)]

Examples:

# Feature addition
feat: add user authentication

# Bug fix
fix: resolve login redirect issue

# Breaking change
feat!: migrate to new API endpoint

# Also breaking change
feat: add new payment method

BREAKING CHANGE: migrate to new payment gateway

# With scope
feat(auth): add password reset functionality

# With body and footer
fix: prevent racing of requests

Introduce a request id and a reference to latest request. Dismiss
incoming responses other than from latest request.

Closes #123

Common Types

feat: A new feature
fix: A bug fix
docs: Documentation changes
style: Code style changes (formatting, missing semicolons, etc.)
refactor: Code refactoring without changing functionality
test: Adding or updating tests
chore: Maintenance tasks, dependency updates

Benefits of Conventional Commits

1. Automatic Version Determination

Conventional commits enable automatic semantic versioning:

feat: triggers a minor version bump (1.0.0 → 1.1.0)
fix: triggers a patch version bump (1.0.0 → 1.0.1)
BREAKING CHANGE: triggers a major version bump (1.0.0 → 2.0.0)

2. Automatic Changelog Generation

Tools can automatically generate changelogs by parsing commit messages, grouping them by type, and extracting relevant information.

Changelog Example

3. Better Project History

Conventional commits create a more readable and searchable project history, making it easier to understand what changes were made and why.

Setting Up Full Automation

To achieve complete automation of versioning and releases, you’ll need several tools working together. Let’s set them up step by step.

1. Commitlint

While not mandatory, Commitlint helps enforce conventional commit standards by linting commit messages.

First, install Commitlint and the Conventional Commits plugin:

npm install --save-dev @commitlint/cli @commitlint/config-conventional

Then you need to set up a configuration.

Simple Project Configuration

For a basic project, create .commitlintrc.json:

{
  "extends": ["@commitlint/config-conventional"]
}

Git Hook

Now you can set up commit validation during git commit, for example using simple-git-hooks, though there are other similar tools available (husky, pre-commit, etc.).

Install simple-git-hooks:

npm install --save-dev simple-git-hooks

Create .simple-git-hooks.json:

{
  "commit-msg": "npx commitlint --edit \"$1\""
}

Now run npx simple-git-hooks to activate the hooks and you’re ready to go!

GitHub Action

You can also set up commit linting via GitHub Actions when commits are pushed to the repository.

Create .github/workflows/commit.yml:

name: Commit Validation

on:
  pull_request:
    types: [opened, synchronize]

jobs:
  commitlint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '18'
          cache: 'npm'

      - name: Install dependencies
        run: npm ci

      - name: Validate commit messages
        run: npx commitlint --from=HEAD~1

Monorepo Project Configuration

In monorepos, it’s common practice to use scopes in Conventional Commits that correspond to workspace names in the monorepo. This helps identify which workspace(s) are affected by each commit. For example:

feat(store): add user authentication state
fix(ui): resolve button styling issue
docs(router): update routing configuration guide

You can use specialized packages to automatically get project scopes:

@commitlint/config-workspace-scopes - for generic workspaces
@commitlint/config-pnpm-scopes - for pnpm workspaces
@commitlint/config-lerna-scopes - for Lerna projects

Let’s look at an example for pnpm workspaces:

Install the packages:

pnpm add -D @commitlint/cli @commitlint/config-conventional @commitlint/config-pnpm-scopes

Create .commitlintrc.js:

import scopes from '@commitlint/config-pnpm-scopes'

export default {
  extends: ['@commitlint/config-conventional', '@commitlint/config-pnpm-scopes'],
  rules: {
    'scope-enum': async (ctx) => {
      const scopeEnum = await scopes.rules['scope-enum'](ctx)
      return [
        scopeEnum[0],
        scopeEnum[1],
        [
          ...scopeEnum[2],
          'deps',     // for Dependabot or Renovate - dependency updates
          'dev-deps', // for Dependabot or Renovate - dev dependency updates
          'release'   // for release commits
        ]
      ]
    }
  },
  prompt: {
    settings: {
      enableMultipleScopes: true
    }
  }
}

2. Commitizen

Commitizen is an optional but very convenient tool that provides an interactive CLI for creating Conventional Commits.

Commitizen CLI Usage Example

First, install Commitizen and the Commitlint adapter:

npm install --save-dev commitizen @commitlint/cz-commitlint

Then create .czrc:

{
  "path": "@commitlint/cz-commitlint"
}

Add a script to package.json:

{
  "scripts": {
    "commit": "cz"
  }
}

Now you can use npm run commit instead of git commit for interactive commit creation.

3. Simple Release Action

The simple-release-action is a comprehensive GitHub Action that automates version updates, changelog generation, and releases. The project is based on simple-release and conventional-changelog.

If you are not using GitHub, you can write your own custom CI script using the @simple-release/core package.

Key Features:

First-class monorepo support - A major differentiator from alternatives
Automatic version bumping based on Conventional Commits
Changelog generation with proper categorization
Git tagging and GitHub releases
Configuration through adapters for different project types

Currently npm and pnpm projects with workspaces are supported (npm adapter, pnpm adapter).

Let’s look at an example of configuring the action for a project with pnpm workspaces using @simple-release/pnpm addon:

Create .simple-release.json config file in repository root:

{
  "project": ["@simple-release/pnpm#PnpmWorkspacesProject", {
    "mode": "fixed"
  }],
  "bump": {
    "extraScopes": ["deps"]
  }
}

extraScopes is used to trigger version bump by commits like fix(deps): ... from Dependabot or Renovate.

Create .github/workflows/release.yml:

name: Release

on:
  issue_comment:
    types: [created, deleted]
  push:
    branches:
      - main

jobs:
  check:
    runs-on: ubuntu-latest
    name: Context check
    outputs:
      continue: ${{ steps.check.outputs.continue }}
      workflow: ${{ steps.check.outputs.workflow }}
    steps:
      - name: Checkout the repository
        uses: actions/checkout@v4
      - name: Context check
        id: check
        uses: TrigenSoftware/simple-release-action@v1
        with:
          workflow: check
          github-token: ${{ secrets.GITHUB_TOKEN }}

  pull-request:
    runs-on: ubuntu-latest
    name: Pull request
    needs: check
    if: needs.check.outputs.workflow == 'pull-request'
    steps:
      - name: Checkout the repository
        uses: actions/checkout@v4
      - name: Create or update pull request
        uses: TrigenSoftware/simple-release-action@v1
        with:
          workflow: pull-request
          github-token: ${{ secrets.GITHUB_TOKEN }}

  release:
    runs-on: ubuntu-latest
    name: Release
    needs: check
    if: needs.check.outputs.workflow == 'release'
    steps:
      - name: Checkout the repository
        uses: actions/checkout@v4
      - name: Install pnpm
        uses: pnpm/action-setup@v2
        with:
          version: 10
      - name: Install Node.js
        uses: actions/setup-node@v4
        with:
          node-version: 18
          cache: 'pnpm'
          registry-url: 'https://registry.npmjs.org'
      - name: Install dependencies
        run: pnpm install
      - name: Release
        uses: TrigenSoftware/simple-release-action@v1
        with:
          workflow: release
          github-token: ${{ secrets.GITHUB_TOKEN }}
          npm-token: ${{ secrets.NPM_TOKEN }}

This workflow consists of three jobs:

check - performs context check to determine if release changes are needed and which workflow to run
pull-request - creates or updates a pull request with release changes
release - performs the actual release when the PR is merged

Every time you push to the main branch, the action will create or update a pull request with a version bump and updated changelog if necessary.

Simple Release Action Pull Request Example

When the pull request is merged, it will automatically release the project.

Simple Release Action Release Example

Conclusion

There is also a recommendation to use squash merge for pull requests to keep the commit history in the main branch clean and well-structured. This ensures that each merge commit follows conventional commit standards and makes the project history more readable.

By implementing Conventional Commits with this toolchain, you’ll have a fully automated release pipeline that maintains consistency, improves project history readability, and reduces manual overhead in version management.

If you want to see real projects using Conventional Commits and their configurations, here are a few examples: