WebpackerCli

Webpacker's conventions for any framework, without Rails. Webpacker was abandoned by the Rails team, and the old version of this tool depended on it (and on a mocked Rails app). Version 1.0 removes that dependency entirely: the gem has no runtime dependencies, and drives plain Webpack 5 through a small, generated webpack.config.js that lives in your project.

You keep the parts of Webpacker that matter:

• config/webpacker.yml (source_path, source_entry_path, public_output_path, extensions, …)
• every file in app/javascript/packs is an entry point
• content-hashed output in public/packs plus a manifest.json for cache invalidation

Prerequisites

Ruby 3.0+, Node.js 20.9+, and Yarn 1.x or npm.

Installation

$ gem install webpacker_cli

Usage

$ webpacker-cli init      # create config + entry pack + package.json, install Node packages
$ webpacker-cli compile   # build packs into public/packs
$ webpacker-cli watch     # rebuild on change
$ webpacker-cli clobber   # remove compiled packs and cache
$ webpacker-cli check     # verify prerequisites
$ webpacker-cli info      # tool versions

The environment comes from WEBPACKER_ENV, NODE_ENV or RAILS_ENV (default development). Production builds use content hashes and minification, e.g. NODE_ENV=production webpacker-cli compile.

The generated config/webpack/webpack.config.js and package.json are yours to edit: add a loader by installing its package and adding a rule, and add the extension to default.extensions in config/webpacker.yml.

Server Tip: It is recommended to compile your assets upon deploy rather than per web request.

Route assets using public/packs/manifest.json:

{
  "application.js": "/packs/application-9578bdd78b657fa4358f.js",
  "application.js.map": "/packs/application-9578bdd78b657fa4358f.js.map"
}

Staying current with Webpack

package.json pins each tool to a major version range (webpack ^5, webpack-cli ^6, …), so yarn upgrade/npm update picks up fixes without breaking changes. A new Webpack major is an explicit, reviewed change to the templates in this gem (and to your project's config when you choose to adopt it) — never a surprise. Existing projects are never overwritten by init unless you pass --force.

Migrating from 0.x

The Rails mock (Gemfile, Rakefile, bin/rails, config/application.rb) and the webpacker:* rake tasks are gone. Delete those files, run webpacker-cli init for the new config, and move any custom loaders from config/webpack/loaders into webpack.config.js rules.

Example Integration

For a good example of using this tool for integrating with your own language see webpacker-rs. This library uses this tool to add Webpacker as part of the default build process of web deployment for the Rust language. In essence the user theirself is responsible for running webpacker-cli init and then webpacker-rs has two methods for deployment which validate dependencies on the server and then compile the assets. After deployment then webpacker-rs also provides a method for looking up the file mappings from the manifest.json file and provides a convenience helper method for dealing with the path routing.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/danielpclark/webpacker-cli

License

The gem is available as open source under the terms of the GNU Lesser General Public License version 3.