Use Rails with faucet-pipeline

Instead of using the built-in asset pipeline of Rails, use faucet-pipeline. This gem enables the required integration with Rails.

You can find an example app here.

Why is an integration like that required? faucet-pipeline modifies the names of the generated files depending on their content (by adding a hash of the file to the name), Rails will not be able to find the files on its own. You still want to be able to use the helpers you are used to like stylesheet_link_tag or image_tag, and they should put out the correct URL for the desired asset. This technique is referred to as cache busting.

So let's say you have a JavaScript file called application.js (for example in app/assets/javascripts) and faucet-pipeline generates a file called application-03118e77692b637cfc0f55bb27fef087.js (for example in public/assets/javascripts) from that file. When you use stylesheet_link_tag 'application.css', you expect that the resulting HTML points to the file containing the hash in its filename. To do that, faucet-pipeline generates a manifest file. In the case of using it with this Gem, it needs to save it as public/assets/manifest.json (to change this, see the Configuration section)

And that's it. This gem will take care of the rest. The resulting HTML will look like this:

<!-- ... -->
<script src="/assets/javascripts/application-03118e77692b637cfc0f55bb27fef087.js" data-turbolinks-track="reload"></script>
<!-- ... -->

The types supported by this gem are:

• stylesheet
• javascript
• image

Installation

Add this line to your application's Gemfile:

gem "faucet_pipeline_rails"

And then execute:

$ bundle

After this, you can ditch sprockets (aka the classic Rails asset pipeline) for good. If you're on an existing Rails app, change the top of your config/application.rb from require 'rails/all' to:

# Pick the frameworks you want:
require "active_record/railtie"
require "active_storage/engine"
require "action_controller/railtie"
require "action_view/railtie"
require "action_mailer/railtie"
require "active_job/railtie"
require "action_cable/engine"
require "rails/test_unit/railtie"
# require "sprockets/railtie" # Disable sprockets in favor of faucet
require "active_model/railtie"

Make sure you customize this to your actual needs. The main takeaway here is to not require "sprockets/railtie" anymore.

For fresh apps, you can just skip sprockets with:

rails new --skip-sprockets

You also need to install faucet-pipeline. Here are the instructions

Configuration

This is a nice starting point for a faucet.config.js:

module.exports = {
  js: [{
    source: "./app/assets/javascripts/application.js",
    target: "./public/assets/javascripts/application.js",
    format: "esm"
  }],

  sass: [{
    source: "./app/assets/stylesheets/application.scss",
    target: "./public/assets/stylesheets/application.css"
  }],

  static: [{
    source: "./app/assets/images",
    target: "./public/assets/images"
  }],

  manifest: {
    target: "./public/assets/manifest.json",
    key: "short",
    webRoot: "./public"
  },

  watchDirs: ["./app/assets"]
};

In this case, your application.html.erb would contain lines like these:

<%= stylesheet_link_tag "application.css", media: "all" %>
<%= javascript_include_tag "application.js", type: "module" %>

By default this gem assumes that your manifest files can be found in public/assets/manifest.json. You can change the path to the manifest file with the following configuration:

config.faucet_pipeline.manifest_path = Rails.root.join("manifest.json")

Note that manifest_path is an absolute path.

This gem also provides a Rake task assets:precompile that runs faucet with the --compact --fingerprint options. It can therefore be used as a drop-in replacement for the task provided by the Rails asset pipeline. It only works if you install your NPM dependencies to the default location (your app's node_modules folder).

Development

After checking out the repo, run bin/setup to install dependencies. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/faucet-pipeline/faucet_pipeline_rails. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.