Use penthouse from npm

.codeclimate.yml

@@ -1,4 +1,2 @@
 languages:
   Ruby: true
-exclude_paths:
-  - lib/penthouse/penthouse.js

.gitignore

@@ -17,3 +17,6 @@ test/version_tmp
 tmp
 
 .DS_Store
+/node_modules/
+.rspec_status
+/npm-debug.log

Gemfile

@@ -1,4 +1,17 @@
-# A sample Gemfile
-source "https://rubygems.org"
+source 'https://rubygems.org'
 
-gem 'rubocop', require: false
+gemspec
+
+group :development, :test do
+  gem 'byebug', platform: [:ruby], require: false
+  gem 'rubocop', require: false
+end
+
+# HACK: npm install on bundle
+unless $npm_commands_hook_installed # rubocop:disable Style/GlobalVars
+  Gem.pre_install do |installer|
+    next true unless installer.spec.name == 'critical-path-css-rails'
+    require_relative './ext/npm/install'
+  end
+  $npm_commands_hook_installed = true # rubocop:disable Style/GlobalVars
+end

README.md

@@ -6,7 +6,7 @@ This gem give you the ability to load only the CSS you *need* on an initial page
 
 This gem assumes that you'll load the rest of the CSS asyncronously. At the moment, the suggested way is to use the [loadcss-rails](https://github.com/michael-misshore/loadcss-rails) gem.
 
-This gem uses [PhantomJS](https://github.com/colszowka/phantomjs-gem) and [Penthouse](https://github.com/pocketjoso/penthouse) to generate the critical CSS.
+This gem uses [Penthouse](https://github.com/pocketjoso/penthouse) to generate the critical CSS.
 
 ## Update
 
@@ -17,7 +17,7 @@ Versions below 0.3.0 are not compatible with this version.  Please read the Upgr
 Add `critical-path-css-rails` to your Gemfile:
 
 ```
-gem 'critical-path-css-rails', '~> 0.4.0'
+gem 'critical-path-css-rails', '~> 1.0.0'
 ```
 
 Download and install by running:
@@ -128,9 +128,9 @@ Answer 'Y' when prompted to overwrite `critical_path_css.rake`.  However, overwr
 The critical-path-css-rails gem follows these version guidelines:
 
 ```
-patch version bump = updates to critical-path-css-rails and patch-level updates to Penthouse and PhantomJS
-minor version bump = minor-level updates to critical-path-css-rails, Penthouse, and PhantomJS
-major version bump = major-level updates to critical-path-css-rails, Penthouse, PhantomJS, and updates to Rails which may be backwards-incompatible
+patch version bump = updates to critical-path-css-rails and patch-level updates to Penthouse
+minor version bump = minor-level updates to critical-path-css-rails and Penthouse
+major version bump = major-level updates to critical-path-css-rails, Penthouse, and updates to Rails which may be backwards-incompatible
 ```
 
 ## Contributing

critical-path-css-rails.gemspec

@@ -10,9 +10,11 @@ Gem::Specification.new do |s|
   s.description = 'Only load the CSS you need for the initial viewport in Rails!'
   s.license     = 'MIT'
 
-  s.add_runtime_dependency 'phantomjs', ['~> 2.1']
-
   s.files        = `git ls-files`.split("\n")
   s.executables  = `git ls-files -- bin/*`.split("\n").map { |f| File.basename(f) }
   s.require_path = 'lib'
+
+  s.add_development_dependency 'rspec', '~> 3.6'
+
+  s.extensions = ['ext/npm/extconf.rb']
 end

ext/npm/extconf.rb

@@ -0,0 +1,3 @@
+File.write 'Makefile',
+           "make:\n\t\ninstall:\n\truby install.rb\nclean:\n\t\n"
+

ext/npm/install.rb

@@ -0,0 +1,4 @@
+require_relative '../../lib/npm_commands'
+
+NpmCommands.new.install('--production', '.') ||
+  raise('Error while installing npm dependencies')

lib/critical-path-css-rails.rb

@@ -1,32 +1,38 @@
-module CriticalPathCss
-  require 'critical_path_css/css_fetcher'
+require 'critical_path_css/configuration'
+require 'critical_path_css/css_fetcher'
+require 'critical_path_css/rails/config_loader'
 
+module CriticalPathCss
   CACHE_NAMESPACE = 'critical-path-css'
 
   def self.generate(route)
-    Rails.cache.write(
+    ::Rails.cache.write(
       route,
-      CssFetcher.new.fetch_route(route),
+      CssFetcher.new(config).fetch_route(route),
       namespace: CACHE_NAMESPACE,
       expires_in: nil
     )
   end
 
   def self.generate_all
-    CssFetcher.new.fetch.each do |route, css|
-      Rails.cache.write(route, css, namespace: CACHE_NAMESPACE, expires_in: nil)
+    CssFetcher.new(config).fetch.each do |route, css|
+      ::Rails.cache.write(route, css, namespace: CACHE_NAMESPACE, expires_in: nil)
     end
   end
 
   def self.clear(route)
-    Rails.cache.delete(route, namespace: CACHE_NAMESPACE)
+    ::Rails.cache.delete(route, namespace: CACHE_NAMESPACE)
   end
 
   def self.clear_matched(routes)
-    Rails.cache.delete_matched(routes, namespace: CACHE_NAMESPACE)
+    ::Rails.cache.delete_matched(routes, namespace: CACHE_NAMESPACE)
   end
 
   def self.fetch(route)
-    Rails.cache.read(route, namespace: CACHE_NAMESPACE) || ''
+    ::Rails.cache.read(route, namespace: CACHE_NAMESPACE) || ''
+  end
+
+  def self.config
+    @config ||= Configuration.new(CriticalPathCss::Rails::ConfigLoader.new.load)
   end
 end

lib/critical_path_css/configuration.rb

@@ -1,39 +1,29 @@
 require 'erb'
 module CriticalPathCss
   class Configuration
-    CONFIGURATION_FILENAME = 'critical_path_css.yml'
 
-    def initialize
-      @configurations = YAML.load(ERB.new(File.read(configuration_file_path)).result)[Rails.env]
+    def initialize(config)
+      @config = config
     end
 
     def base_url
-      @configurations['base_url']
+      @config['base_url']
     end
 
     def css_path
-      @css_path ||= begin
-        relative_path = @configurations['css_path'] || manifest_path
-        "#{Rails.root}/public#{relative_path}"
-      end
+      @config['css_path']
     end
 
     def manifest_name
-      @configurations['manifest_name']
+      @config['manifest_name']
     end
 
     def routes
-      @configurations['routes']
+      @config['routes']
     end
 
-    private
-
-    def configuration_file_path
-      @configuration_file_path ||= Rails.root.join('config', CONFIGURATION_FILENAME)
-    end
-
-    def manifest_path
-      @manifest_path ||= ActionController::Base.helpers.stylesheet_path(manifest_name, host: '')
+    def penthouse_options
+      @config['penthouse_options'] || {}
     end
   end
 end

lib/critical_path_css/css_fetcher.rb

@@ -1,12 +1,12 @@
+require 'json'
+require 'open3'
+
 module CriticalPathCss
   class CssFetcher
-    require 'phantomjs'
-    require 'critical_path_css/configuration'
-
-    PENTHOUSE_PATH = "#{File.dirname(__FILE__)}/../penthouse/penthouse.js"
+    GEM_ROOT = File.expand_path(File.join('..', '..'), File.dirname(__FILE__))
 
-    def initialize
-      @config = Configuration.new
+    def initialize(config)
+      @config = config
     end
 
     def fetch
@@ -20,15 +20,50 @@ def fetch_route(route)
     protected
 
     def css_for_route(route)
-      url = @config.base_url + route
-
-      Phantomjs.run(
-        '--ignore-ssl-errors=true',
-        '--ssl-protocol=tlsv1',
-        PENTHOUSE_PATH,
-        url,
-        @config.css_path
-      )
+      options = {
+        'url' => @config.base_url + route,
+        'css' => @config.css_path,
+        ## optional params
+        # viewport dimensions
+        'width' => 1300,
+        'height' => 900,
+        # CSS selectors to always include, e.g.:
+        'forceInclude' => [
+          #  '.keepMeEvenIfNotSeenInDom',
+          #  '^\.regexWorksToo'
+        ],
+        # ms; abort critical CSS generation after this timeout
+        'timeout' => 30000,
+        # set to true to throw on CSS errors (will run faster if no errors)
+        'strict' => false,
+        # characters; strip out inline base64 encoded resources larger than this
+        'maxEmbeddedBase64Length' => 1000,
+        # specify which user agent string when loading the page
+        'userAgent' => 'Penthouse Critical Path CSS Generator',
+        # ms; render wait timeout before CSS processing starts (default: 100)
+        'renderWaitTime' => 100,
+        # set to false to load (external) JS (default: true)
+        'blockJSRequests' => true,
+        # see `phantomjs --help` for the list of all available options
+        'phantomJsOptions' => {
+          'ignore-ssl-errors' => true,
+          'ssl-protocol' => 'tlsv1'
+        },
+        'customPageHeaders' => {
+          # use if getting compression errors like 'Data corrupted':
+          'Accept-Encoding' => 'identity'
+        }
+      }.merge(@config.penthouse_options)
+      out, err, st = Dir.chdir(GEM_ROOT) do
+        Open3.capture3('node', 'lib/fetch-css.js', JSON.dump(options))
+      end
+      if !st.exitstatus.zero? || out.empty? && !err.empty?
+        STDOUT.puts out
+        STDERR.puts err
+        raise "Failed to get CSS for route #{route}\n" \
+              "  with options=#{options.inspect}"
+      end
+      out
     end
   end
 end

lib/critical_path_css/rails/config_loader.rb

@@ -0,0 +1,24 @@
+module CriticalPathCss
+  module Rails
+    class ConfigLoader
+      CONFIGURATION_FILENAME = 'critical_path_css.yml'
+
+      def load
+        config = YAML.load(ERB.new(File.read(configuration_file_path)).result)[::Rails.env]
+        config['css_path'] = "#{::Rails.root}/public" + (
+            config['css_path'] ||
+              ActionController::Base.helpers.stylesheet_path(
+                config['manifest_name'], host: ''
+              )
+        )
+        config
+      end
+
+      private
+
+      def configuration_file_path
+        @configuration_file_path ||= ::Rails.root.join('config', CONFIGURATION_FILENAME)
+      end
+    end
+  end
+end

lib/critical_path_css/rails/version.rb

@@ -1,6 +1,5 @@
 module CriticalPathCSS
   module Rails
-    VERSION = '0.4.0'
-    PENTHOUSE_VERSION = '0.3.4'
+    VERSION = '1.0.0'
   end
 end

lib/fetch-css.js

@@ -0,0 +1,14 @@
+const penthouse = require('penthouse');
+const fs = require('fs');
+
+const penthouseOptions = JSON.parse(process.argv[2]);
+
+const STDOUT_FD = 1;
+const STDERR_FD = 2;
+
+penthouse(penthouseOptions).then(function(criticalCss) {
+  fs.writeSync(STDOUT_FD, criticalCss);
+}).catch(function(err) {
+  fs.writeSync(STDERR_FD, err);
+  process.exit(1);
+});

lib/npm_commands.rb

@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+# NPM wrapper with helpful error messages
+class NpmCommands
+
+  # @return [Boolean] whether the installation succeeded
+  def install(*args) # rubocop:disable Metrics/MethodLength
+    return false unless check_nodejs_installed
+    STDERR.puts 'Installing npm dependencies...'
+    install_status = Dir.chdir File.expand_path('..', File.dirname(__FILE__)) do
+      system('npm', 'install', *args)
+    end
+    STDERR.puts(
+      *if install_status
+         ['npm dependencies installed']
+       else
+         ['-' * 60,
+          'Error: npm dependencies installation failed',
+          '-' * 60]
+       end
+    )
+    install_status
+  end
+
+  private
+
+  def check_nodejs_installed # rubocop:disable Metrics/MethodLength
+    return true if executable?('node')
+    STDERR.puts(
+      '-' * 60,
+      'Error: critical-path-css-rails requires NodeJS and NPM.',
+      *if executable?('brew')
+         ['  To install NodeJS and NPM, run:',
+          '  brew install node']
+       elsif Gem.win_platform?
+         ['  To install NodeJS and NPM, we recommend:',
+          '  https://github.com/coreybutler/nvm-windows/releases']
+       else
+         ['  To install NodeJS and NPM, we recommend:',
+          '  https://github.com/creationix/nvm']
+       end,
+      '-' * 60
+    )
+  end
+
+  def executable?(cmd)
+    exts = ENV['PATHEXT'] ? ENV['PATHEXT'].split(';') : ['']
+    ENV['PATH'].split(File::PATH_SEPARATOR).each do |path|
+      exts.each do |ext|
+        exe = File.join(path, "#{cmd}#{ext}")
+        return exe if File.executable?(exe) && !File.directory?(exe)
+      end
+    end
+    nil
+  end
+end