Lerna-Lite

Lerna-Lite is a super light version of the original Lerna

• About Lerna-Lite
  • Why create this lib/fork?
• Getting Started
• How It Works
• Installation
  • JSON Schema
  • Migration for existing Lerna users
• Project Demo - See it in Action
• README Badge
• lerna.json config file
• Contributions
• Troubleshooting
• Available Commands (they are all optional, refer to the Installation table shown below)
  • click on any of the command link below to see dedicated documentation and available options
  • 🛠️ init - creates a new Lerna-Lite workspace structure and adds lerna.json
    • this is the only command (init) included with the CLI
  • 🕜 changed - list local packages that changed since last tagged release
  • 🌓 diff - git diff all packages or a single package since the last release
  • 👷 exec - execute shell command in each workspace package
  • 📖 list - list local packages
  • ☁️ publish - publish every workspace packages that changed
  • 📑 version - create new version for each workspace packages
  • 🏃 run - run npm script, in topological order, in each workspace package
  • 👓 watch - watch for changes within packages and execute commands

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📢 Lerna-Lite supports pnpm/yarn workspace: protocol

Take 30sec. to complete this 1 question poll survey 🔘 if you are using this feature. It's a simple poll to find out which package manager is the most popular with workspace: protocol feature (so far, about 60% pnpm and 40% yarn).

Lerna-Lite itself is also using pnpm workspaces with the workspace: protocol 🎉

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Who is using Lerna-Lite

Here are some of the largest projects using Lerna-Lite

Jest   |   React Navigation   |   Format.JS   |   Volar   |   Blueprint   |   NativeScript

License

MIT License

About Lerna-Lite

Lerna-Lite differs from the original Lerna since it only has a limited subset of its original commands (which itself has 15 commands) and they are all optional in Lerna-Lite making its install footprint a lot smaller. Lerna was originally built as an all-in-one tool, however nowadays Workspaces are available in all package managers and the need for an all-in-one tool, which includes built-in workspaces functionalities (like bootstrap), is no longer needed. Lerna-Lite is built around this new reality and is only providing commands that package managers do not include. To summarize, Lerna-Lite is more modular than the original Lerna and you'll end up installing a lot less dependencies while also making it more versatile to use with other tools like TurboRepo, pnpm and others...

Lerna-Lite assumes, and requires you to pre-setup your Workspace through your favorite package manager (npm, pnpm, yarn) that will take care of the symlinks. Lerna-Lite does not include the bootstrap, add, create neither link commands hence the need for you to properly setup your workspace prior to installing Lerna-Lite.

According to your needs, choose the best option to setup a workspace: npm 7+ | Yarn classic | Yarn 2+ | pnpm

Why create this lib/fork?

Below are the main reasons as to why this fork was created:

1. Lerna's repo was unmaintained for nearly 2 years (in early 2022, Lerna's dependencies were really out of date)
   • Lerna is now maintained again since Nrwl, the company behind Nx, took over stewardship of Lerna
     • please note that Lerna-Lite fork was created couple months before Nrwl took over Lerna
     • we also replicate Lerna's PRs whenever possible (except for Nx specific changes which are skipped)
2. A desire to create a smaller and lighter alternative compared to the original all-in-one Lerna tool
   • Lerna-Lite is entirely modular, all commands are totally optional (install only what you really need).
3. The project was rewritten in TypeScript and also built as ESM only since v2.0 (you can still use it in a CJS environment)
4. Newer Lerna versions v5.5+ are now requiring and installing Nx, however not the case in Lerna-Lite
   • note, if you already use Nx then it's probably better to use Lerna, otherwise Lerna-Lite is the real alternative
   • if you use other tools like TurboRepo and install the original Lerna, you end up with 2 similar tools (not good)
5. Lerna-Lite added a few unique features (not available in Lerna itself):
   • workspace: protocol support
     • Lerna added support for the same feature 6 months later in their v6.0 release
   • --dry-run to preview version/publish & changelogs locally (will show git changes without committing them)
   • lerna version --changelog-header-message "msg" for showing banner or sponsors in your changelogs
   • lerna version --changelog-include-commits-client-login to add PR contributors in GitHub releases
   • lerna version --allow-peer-dependencies-update to also updated your peer dependencies
   • lerna version --skip-bump-only-releases to avoid cluttering your GitHub releases with independent mode
   • lerna version --sync-workspace-lock to sync lock file before publishing (not needed w/workspace: protocol)
   • lerna publish --remove-package-fields (remove certain fields from package.json before publishing)
     • ie: Lerna-Lite itself uses it to remove scripts and devDependencies

On a final note, the best feature of Lerna-Lite (versus Lerna) has to be its modularity. A large portion of the users are only interested in version/publish commands but on the other hand, a small minority are only interested in other commands like lerna run/exec. Lerna-Lite offers this kind of flexibility by allowing the user to choose what to install (see installation below) which help to keep your download to the bare minimum.

Lerna-Lite will help you with the following:

Note all commands are optional in Lerna-Lite, refer to the Installation table for more info

Version and Publish commands

• Automate the creation of new Versions (independent or fixed version) of all your workspace packages.
  • it will automatically Commit/Tag your new Version & create new GitHub/GitLab Release (when enabled).
• Automate, when enabled, the creation of Changelogs for all your packages by reading your Conventional Commits.
• Automate, the repository Publishing of your new version(s) for all your packages (on NPM or other platforms).

Other optional commands

• Changed command, when installed, will list all local packages that have changed since the last tagged release
• Diff command, when installed, will show git diff of all packages or a single package since the last release
• Exec command, when installed, will help you execute shell commands in parallel and in topological order.
• List command, when installed, will list all workspace local packages
• Run command, when installed, will help you run npm script in parallel and in topological order.
• Watch command, when installed, will watch for changes within all packages and execute certain commands

README Badge

[![lerna--lite](https://img.shields.io/badge/maintained%20with-lerna--lite-e137ff)](https://github.com/lerna-lite/lerna-lite)

Getting Started

Let's start by installing Lerna-Lite CLI as a dev dependency to your project and then run the init command to get started (see init#readme for all options). Note that the CLI must be installed at all time, then proceed by installing any other optional commands (the CLI is only including the init command), refer to the Installation table for more info.

# install Lerna-Lite CLI locally or globally (`init` is the only command installed)
$ npm install -g @lerna-lite/cli # pnpm add -g @lerna-lite/cli

# create your monorepo and initialize lerna-lite
$ mkdir lerna-repo
$ cd lerna-repo
$ npx lerna init # OR pnpm exec lerna init

# for npm/yarn (only) workspaces add --use-workspaces
$ npx lerna init --use-workspaces

This will create a lerna.json configuration file as well as a packages folder, so your folder should now look like this:

lerna-repo/
  packages/
    package-a
  package.json
  lerna.json

Note Lerna-Lite now supports 3 file extension types (.json, .jsonc and .json5), however not all code editors support JSON Schema with .json5, so lerna.json might still be the preferred extension (all formats support inline comments, even .json).

Note that package-a will not be created, it is only shown here to help clarify the structure. For more info and full details about the lerna.json file, you can read the lerna.json Wiki. Also note that you can optionally add comments to your lerna.json config file since it is also able to parse JSON5 file format.

The final step will be to install the commands that are of interest to you (publish, version, run, exec, ...)

$ npm i @lerna-lite/publish -D

How It Works

Lerna allows you to manage your project using one of two modes: Fixed or Independent.

Fixed/Locked mode (default)

Fixed mode Lerna projects operate on a single version line. The version is kept in the lerna.json file at the root of your project under the version key. When you run lerna publish, if a module has been updated since the last time a release was made, it will be updated to the new version you're releasing. This means that you only publish a new version of a package when you need to.

Note: If you have a major version zero, all updates are considered breaking. Because of that, running lerna publish with a major version zero and choosing any non-prerelease version number will cause new versions to be published for all packages, even if not all packages have changed since the last release.

This is the mode that Jest) is currently using. Use this if you want to automatically tie all package versions together. One issue with this approach is that a major change in any package will result in all packages having a new major version.

Independent mode

lerna init --independent

Independent mode Lerna projects allows maintainers to increment package versions independently of each other. Each time you publish, you will get a prompt for each package that has changed to specify if it's a patch, minor, major or custom change.

Independent mode allows you to more specifically update versions for each package and makes sense for a group of components. Combining this mode with something like semantic-release would make it less painful. (There is work on this already at atlassian/lerna-semantic-release).

Set the version key in lerna.json to independent to run in independent mode.

Installation

Lerna-Lite is entirely modular, as opposed to Lerna, and installing the CLI locally or globally will only provide you the init command. Please make sure to install other commands that you are interested in (see table below).

If you are new to Lerna-Lite, you could also run the lerna init command which will create the lerna.json for you with a minimal structure setup. If you are using a client other than npm, then make sure to update the npmClient property in lerna.json (for example: "npmClient": "yarn" or "pnpm").

Note please make sure that you have a lerna.json config file created and a version property defined with either a fixed or independent mode. An error will be thrown if you're missing any of them.

JSON Schema

You can add the $schema property into your lerna.json to take advantage of Lerna-Lite JSON Schema (lerna init can help setting it up for you). This will help with the developer experience, users will be able to see what properties are valid with their types and a brief description of what each option does (descriptions are pulled from their associated lerna command options documentation).

lerna.json

{
  "$schema": "node_modules/@lerna-lite/cli/schemas/lerna-schema.json",
  // ...

  // or from GitHub CDN
  "$schema": "https://raw.githubusercontent.com/lerna-lite/lerna-lite/main/packages/cli/schemas/lerna-schema.json",
}

Note JSON Schema might not be well supported by all code editors with .json5, use lerna.json if that is a problem for you.

Separate / Optional Installs

Command	Install	Description
☁️ publish	npm i @lerna-lite/publish -D	publish each workspace package
📑 version	npm i @lerna-lite/version -D	create new version for each workspace package
🕜 changed	npm i @lerna-lite/changed -D	list local packages changed since last release
🌓 diff	npm i @lerna-lite/diff -D	git diff all packages since the last release
👷 exec	npm i @lerna-lite/exec -D	execute an command in each workspace package
📖 list	npm i @lerna-lite/list -D	list local packages
🏃 run	npm i @lerna-lite/run -D	run npm script in each workspace package
👓 watch	npm i @lerna-lite/watch -D	watch for changes & execute commands when fired

Note since the publish package depends on the version package, you could simply install @lerna-lite/publish to automatically gain access to both commands.

Usage

Add custom NPM scripts or simply run the commands in your shell with the Lerna-Lite CLI, you can see below some very basic Lerna npm script samples.

// package.json / npm scripts
"scripts": {
  "new-version": "lerna version",
  "new-publish": "lerna publish from-package",
  "preview:new-version": "lerna version --dry-run",
  "run-tests": "lerna run test",
}

Migration for existing Lerna users

Migrating from the original Lerna, should be fairly easy since you simply need to replace your Lerna dependency with Lerna-Lite @lerna-lite/cli, and you will need to manually install the command(s) that you are interested in and that's about it. The CLI commands and options are nearly the same. The biggest difference compared to Lerna is that you need to install the commands that you are interested in, for that take a look at the steps shown below:

Note as opposed to Lerna v7 and higher, the useWorkspace is not enabled by default in Lerna-Lite and we still recommend to use either useWorkspaces for Yarn/NPM or use the default packages in lerna.json for pnpm users. The useWorkspaces has some drawback since some of the packages could be unrelated to the project releases (ie: website, examples) and for this use case the packages/* defined in lerna.json is a better approach (i.e. Jest uses this approach).

1. remove Lerna from your local & global dependencies

npm uninstall lerna      # OR yarn remove lerna -W
npm uninstall -g lerna   # OR yarn global remove lerna

2. install Lerna-Lite CLI, note this only provides you the init command

# Lerna CLI (includes `init`)
npm install @lerna-lite/cli -D

3. then install any of the optional Lerna-Lite command(s) that you wish to use (changed, diff, exec, list, run, publish, version and/or watch) refer to installation table above

# for example, let's install publish (note publish will automatically give you version since it's a dependency)
npm install @lerna-lite/publish -D

4. review your lerna.json config file and remove any unrelated command options, for example bootstrap does not exist in Lerna-Lite so there's no need to keep that config

{
    "npmClient": "yarn",
    "command": {
        "version": {
            "conventionalCommits": true
        },
-       "bootstrap": {
-           "npmClientArgs": ["--no-package-lock"]
-       }
    }
}

Note after switching to Lerna-Lite and publishing your next release with conventional-changelog, you will probably see a lot of diff changes across your changelog.md files, a lot of empty lines will be deleted, and that is totally expected since Lerna-Lite has code in place to remove these unnecessary empty lines.

Project Demo?

You want to see a project demo? Sure... you're looking at it 😉

Yes indeed, this project was originally created as an NPM Workspace and later migrated to a pnpm workspaces for the sole purpose of demoing and testing its own code. All changelogs and versions are created and published by the lib itself, how sweet is that? You can also see that this project has its own lerna.json config file as well to run properly (take a look to see how it works).

See it in Action 🎦

You can see a small video of a new version release on this Release Demo - Wiki to demonstrate its usage. Are you confused with all these options? Perhaps taking a look at some of the references shown below might help you get started.

Good Lerna Tutorials / References

• Release Demo - Wiki - Lerna-Lite demo (animated gif)
• How to Use Lerna - YouTube video
• Lerna Release Workflow - GitHub Template

Contributions

Contributions are very well encouraged. Also please note that the original code was created by much smarter persons that myself and my knowledge of the project might still lack in some areas of the project. The main goal of this fork was to make it more modular and keep dependencies up to date (Renovate was put in place and is running weekly).

Development / Contributions

To contribute to the project, please follow the steps shown in the Contributing Guide

Troubleshooting

If you have problems running the project and your problems are related to Git commands that were executed, we then suggest to first try with the --dry-run option to see if it helps in finding the error(s) that you may have. Another great, and possibly much more useful suggestion, is to search in the original Lerna issues list and see if any solution could help you (remember that Lerna-Lite is a fork of the original code from Lerna and it works the same way). Lastly, if that is not enough and you wish to troubleshoot yourself, then read this Troubleshooting - Wiki to possibly troubleshoot yourself the execution in your own environment.

Published Packages

Package Name	Version	Description	Changes
@lerna-lite/cli		Lerna-Lite CLI required to execute any command	changelog
@lerna-lite/core		Lerna-Lite core & shared methods (internal use)	changelog
@lerna-lite/init		Setup your monorepo to use Lerna-Lite	changelog
@lerna-lite/publish		Publish packages in the current workspace	changelog
@lerna-lite/version		Bump Version & write Changelogs	changelog
@lerna-lite/exec		Execute shell command in current workspace	changelog
@lerna-lite/changed		List local packages that changed since last release	changelog
@lerna-lite/diff		Diff all packages or a single package since last release	changelog
@lerna-lite/list		List local packages	changelog
@lerna-lite/listable		Listable utils used by list and changed commands (internal use)	changelog
@lerna-lite/npmlog		inline version of npmlog util (mostly for internal usage)	changelog
@lerna-lite/profiler		Lerna-Lite Profiler used by some optional commands (internal use)	changelog
@lerna-lite/run		Run npm scripts in current workspace	changelog
@lerna-lite/watch		Watch for pkg changes and execute callback commands	changelog

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