Start bundling compiled assets in the Gem (#2397)

Taking inspiration from how Avo handles their gem assets, this bundles a
compiled version of our assets inside the gem.

We're using `jsbundling-rails` with `esbuild`, along with `cssbundling-rails`
with `saas` to build Administrate's asset files, which is the closest of
the newer approaches for handling assets in Rails as to what we'd been doing
previously.

We then remove `jquery-rails`, `sassc-rails` and `selectize-rails` gems
which are replaced with the equivalents from `npm`.

When releasing, we'll need to run `yarn run build` and `yarn run
build:css` to compile the assets before building the gem which will now
ship the contents of `app/assets/builds` with it.

For someone using Administrate, they'll no longer need to compile
the assets shipped by it as these will now be ready-to-use `.js` and
`.css` files and any asset bundling approaches we choose (or need to,
because they've changed upstream in Rails) should no longer have an
impact on users of the gem.

This is part of: #2311

https://avohq.io/blog/how-to-bundle-assets-in-a-rails-engine

Co-authored-by: Pablo Brasero <pablo@pablobm.com>

.github/workflows/main.yml

@@ -39,15 +39,23 @@ jobs:
         with:
           ruby-version: ${{ matrix.ruby }}
           bundler-cache: true
-      - name: Install dependencies
+      - name: Set up JS
+        uses: actions/setup-node@v4
+        with:
+          cache: yarn
+      - name: Install Ruby dependencies
         run: bundle install
       - name: Install Appraisal dependencies
         run: bundle exec appraisal install
+      - name: Install JS dependencies
+        run: yarn install
       - name: Setup the environment
         run: cp .sample.env .env
       - run: cp spec/example_app/config/database.yml.sample spec/example_app/config/database.yml
       - name: Setup the database
         run: bundle exec rake db:setup
+      - name: Build assets
+        run: yarn run build && yarn run build:css
       - name: Run tests
         run: bundle exec rspec
       - name: Appraise Rails 6.0

.gitignore

@@ -7,17 +7,28 @@
 /.foreman
 /coverage/*
 /db/*.sqlite3
+
 /log/*
 /tmp/*
 !/log/.keep
 !/tmp/.keep
+
 /spec/example_app/log/*
 /spec/example_app/tmp/*
 !/spec/example_app/log/.keep
 !/spec/example_app/tmp/.keep
 /spec/example_app/public/system
 /spec/example_app/public/assets
+
+/spec/example_app/app/assets/builds/*
+!/spec/example_app/app/assets/builds/.keep
+
+/spec/example_app/node_modules
 /spec/example_app/config/database.yml
+
+/node_modules
+/public
+
 /tags
 pkg
 *.ipr
@@ -28,3 +39,4 @@ pkg
 gemfiles/.bundle/
 .yardoc
 /doc
+*.gem

.sample.env

@@ -1,3 +1,4 @@
 # http://ddollar.github.com/foreman/
 RACK_ENV=development
 SECRET_KEY_BASE=development_secret
+PORT=3000

Gemfile

@@ -15,6 +15,10 @@ gem "sentry-rails"
 gem "sentry-ruby"
 gem "unicorn"
 
+gem "cssbundling-rails", "~> 1.2"
+gem "jsbundling-rails", "~> 1.1"
+gem "sprockets-rails", "~> 3.4"
+
 group :development, :test do
   gem "appraisal"
   gem "awesome_print"

Gemfile.lock

@@ -5,10 +5,7 @@ PATH
       actionpack (>= 6.0, < 8.0)
       actionview (>= 6.0, < 8.0)
       activerecord (>= 6.0, < 8.0)
-      jquery-rails (~> 4.6.0)
       kaminari (~> 1.2.2)
-      sassc-rails (~> 2.1)
-      selectize-rails (~> 0.6)
 
 GEM
   remote: https://rubygems.org/
@@ -116,6 +113,8 @@ GEM
     crack (0.4.5)
       rexml
     crass (1.0.6)
+    cssbundling-rails (1.4.0)
+      railties (>= 6.0.0)
     database_cleaner (2.0.2)
       database_cleaner-active_record (>= 2, < 3)
     database_cleaner-active_record (2.1.0)
@@ -137,7 +136,6 @@ GEM
       railties (>= 5.0.0)
     faker (3.2.3)
       i18n (>= 1.8.11, < 2)
-    ffi (1.15.5)
     formulaic (0.4.1)
       activesupport
       capybara
@@ -160,10 +158,8 @@ GEM
       rails-i18n
       rainbow (>= 2.2.2, < 4.0)
       terminal-table (>= 1.5.1)
-    jquery-rails (4.6.0)
-      rails-dom-testing (>= 1, < 3)
-      railties (>= 4.2.0)
-      thor (>= 0.14, < 2.0)
+    jsbundling-rails (1.3.0)
+      railties (>= 6.0.0)
     kaminari (1.2.2)
       activesupport (>= 4.1.0)
       kaminari-actionview (= 1.2.2)
@@ -279,15 +275,6 @@ GEM
       rspec-support (~> 3.12)
     rspec-support (3.12.1)
     rubyzip (2.3.2)
-    sassc (2.4.0)
-      ffi (~> 1.9)
-    sassc-rails (2.1.2)
-      railties (>= 4.0.0)
-      sassc (>= 2.0)
-      sprockets (> 3.0)
-      sprockets-rails
-      tilt
-    selectize-rails (0.12.6)
     selenium-webdriver (4.17.0)
       base64 (~> 0.2)
       rexml (~> 3.2, >= 3.2.5)
@@ -311,7 +298,6 @@ GEM
     terminal-table (3.0.2)
       unicode-display_width (>= 1.1.1, < 3)
     thor (1.3.0)
-    tilt (2.2.0)
     timecop (0.9.8)
     timeout (0.4.0)
     tzinfo (2.0.6)
@@ -347,6 +333,7 @@ DEPENDENCIES
   awesome_print
   byebug
   capybara
+  cssbundling-rails (~> 1.2)
   database_cleaner
   dotenv-rails
   factory_bot_rails
@@ -355,6 +342,7 @@ DEPENDENCIES
   front_matter_parser
   globalid
   i18n-tasks (= 1.0.13)
+  jsbundling-rails (~> 1.1)
   kaminari-i18n
   launchy
   pg
@@ -366,6 +354,7 @@ DEPENDENCIES
   sentry-rails
   sentry-ruby
   shoulda-matchers
+  sprockets-rails (~> 3.4)
   timecop
   uglifier
   unicorn

Procfile.dev

@@ -0,0 +1,3 @@
+web: bundle exec unicorn -p $PORT -c ./config/unicorn.rb
+js: yarn build --watch
+css: yarn build:css --watch

administrate.gemspec

@@ -16,11 +16,7 @@ Gem::Specification.new do |s|
   s.add_dependency "actionpack", ">= 6.0", "< 8.0"
   s.add_dependency "actionview", ">= 6.0", "< 8.0"
   s.add_dependency "activerecord", ">= 6.0", "< 8.0"
-
-  s.add_dependency "jquery-rails", "~> 4.6.0"
   s.add_dependency "kaminari", "~> 1.2.2"
-  s.add_dependency "sassc-rails", "~> 2.1"
-  s.add_dependency "selectize-rails", "~> 0.6"
 
   s.description = <<-DESCRIPTION
 Administrate is heavily inspired by projects like Rails Admin and ActiveAdmin,