Use npm as part of your Rails asset pipeline
npm-pipeline-rails allows you to use any toolchain to build your asset files in Rails 4.2+. This allows you to:
- Use Brunch with Rails (instructions)
- Use Gulp with Rails (instructions)
- Use Webpack with Rails (instructions)
- Use Grunt with Rails
- Use Browserify with Rails
- Use Broccoli with Rails
- Use any other asset tool with Rails
See § How it Works for an explanation of the diagram above.
⚠️ Notice ⚠️
Rails 5.1 will be adding official support for Webpack via webpacker. In contrast, npm-pipeline-rails is far less opinionated and more flexible than webpacker, but expect better support from using Rails's official integration.
Add this line below to your
Gemfile. After that, proceed with an automated or manual setup.
Use the generators for your preferred build tool:
- Brunch -
./bin/rails generate npm_pipeline:brunch
- Gulp -
./bin/rails generate npm_pipeline:gulp
- Webpack -
./bin/rails generate npm_pipeline:webpack
- Put together a setup with Brunch, Broccoli, Gulp, Webpack or any other tool. It should:
- Take source files from
- Render CSS to
- Render JS to
webpackwith whatever build tool you use.)
- Take source files from
- Create a
buildscripts to point to this setup. (See example)
start- Configure this script to run a development file watcher.
build- Configure this script to run a production compiler.
- Add your expected compiled assets to
Set up support for tests
If you're using continuous integration for your tests, configure it to run this before your tests:
npm run build
For tests running in your development machine, ensure that asset files are available when running your tests. This means starting your dev server at least once before running tests, or invoking
npm run build manually.
Disable some gems
You may also want to disable some gems, depending on your set up:
uglifyjsif you already do minification in your npm tool.
autoprefixer-railsif you already do autoprefixing in your npm tool.
sprockets-es6if you already do ES6 compiling in your npm tool.
- and so on...
$ heroku buildpacks:set heroku/ruby $ heroku buildpacks:add --index 1 heroku/nodejs Buildpack added. Next release on my-app-name will use: 1. heroku/nodejs 2. heroku/ruby
It's recommended to turn off
config.npm.install_on_asset_precompile to make deployments faster; see § Configuration.
npm-pipeline-rails provides these configuration options below. Put them inside
config/application.rb (not in an initializer!).
# These are defaults; in most cases, you don't need to configure anything. Rails.application.configure do # Enables npm_pipeline_rails's invocation of `watch` commands. (v1.5.0+) # If `true`, watch commands will be ran alongside Rails's server. # Defaults to true in development. config.npm.enable_watch = Rails.env.development? # Command to install dependencies config.npm.install = ['npm install'] # Command to build production assets config.npm.build = ['npm run build'] # Command to start a file watcher config.npm.watch = ['npm run start'] # The commands are arrays; you may add more commands as needed: config.npm.watch = [ 'npm run webpack:start', 'npm run brunch:start' ] # If 'true', runs 'npm install' on 'rake assets:precompile'. (v1.6.0+) # If you disable this, you'll need to run `npm install` yourself. # This is generally desired, but you may set this to false when # deploying to Heroku to speed things up. config.npm.install_on_asset_precompile = true # If 'true', runs 'npm install' on 'rails server'. (v1.7.0+) # If you disable this, you'll need to run `npm install` yourself. config.npm.install_on_rails_server = true end
How it works
npm-pipeline-rails allows you to hook certain commands, usually npm scripts, during the Rails app lifecycle. It assumes that your tool will build plain JS and CSS files into
vendor/assets, allowing it to be picked up by Rails's asset pipeline.
It does not replace the Rails asset pipeline, but rather it works with it. The files you build with your npm pipeline will be available as regular files in the Rails asset pipeline.
When starting a Rails development server (
bundle exec rails s), it runs the
install command. After that, it starts a background process that runs your
rake assets:precompile, it will first run the
install command then the
Consult railtie.rb for the actual code that makes all these happen.
Rails.application.configure do # ... config.npm.install = ['yarn'] end
Skipping Rails asset pipeline
The recommended setup renders files to
webpack with whatever build tool you use.) You may opt to output to
This is not recommended since you will miss out on automatic asset fingerprinting, among other nice integrations.
If you do this, you will need to run
npm run build as part of your deploy script and CI test script.
Rails's asset pipeline was a great step forward for Rails 3. For today's requirements however, it doesn't always come with all the tools you need. npm-pipeline-rails lets you outsource asset building complexities to Node.js-based tools.
- webpack-assets - integration for webpack-dev-server
- browserify-rails - browserify for the asset pipeline