olivierlacan · February 16, 2023 10:37 · olivierlacan · Jul 9, 2016
diff --git a/assets.rake b/assets.rake
 # These instance variables allow you to define which tags we should check 
 # to find references to JavaScript and CSS files. 
 # 
 # Included first are the Rails defaults `javascript_include_tag` and 
 # `stylesheet_link_tag`. Next are examples of custom methods we use at 
 # Code School with the content_for method in order to include JS/CSS in
 # specific location such as the <head> tag in this instance.
 JS_TAGS = %w[ javascript_include_tag included_javascript_for_head ]
 CSS_TAGS = %w[ stylesheet_link_tag linked_stylesheet_for_head ]

 # This task will first run `git grep` to find any instance in your git repo 
 # of the JS_TAGS and CSS_TAGS. It will then consult the Sprockets manifest and 
 # check for matching logical paths for the files references by your JavaScript 
 # and CSS tags. If the task can't find a mention of the assets you reference
 # in your tags within the Sprockets manifest, you will see them listed as 
 # output. You should double-check that these references correspond to files 
 # that are added to config.assets.precompile.
 # 
 # It's likely that these files are not being properly precompiled which means 
 # they're either going to 404 in production (if you have config.assets.compile 
 # set to false) or cause a slow on-demand compilation (if you have 
 # config.assets.compile set to true)
 namespace :assets do
  desc 'Check for non-precompiled assets'
  task :missing_precompile => :environment do
    javascripts = fetch_references(:js)
    stylesheets = fetch_references(:css)

    missing_js_precompiles = check_for_precompiled(javascripts)
    missing_css_precompiles = check_for_precompiled(stylesheets)

    if missing_js_precompiles.present? 
      puts "Missing JavaScript precompiles: "
      puts missing_js_precompiles
    else
      puts "No missing JavaScript precompiles found."
    end

    if missing_css_precompiles.present? 
      puts "Missing CSS precompiles: "
      puts missing_css_precompiles
    else
      puts "No missing CSS precompiles found."
    end
  end

  def sprockets_manifest_path
    Dir.glob("public/assets/.sprockets-manifest-*.json").first
  end

  def manifest
    if sprockets_manifest_path.present?
      JSON.parse File.read(sprockets_manifest_path)
    else
      raise "No Sprockets Manifest Found: you need to run `bundle exec rake assets:precompile` first."
    end
  end

  def logical_paths
    manifest["files"].map { |script| script.last["logical_path"] }
  end

  def check_for_precompiled(paths)
    paths.values.uniq.reject do |script_path|
      script_path.start_with?(*exclusion_prefixes) or
      logical_paths.any? { |path| path.include?(script_path) }
    end
  end

  def exclusion_prefixes
    # // means protocol-less file which means non-local
    %w[ // ]
  end

  def grep(method)
    %x{ git grep #{method} -- `git ls-files | grep app/views` }
  end

  def fetch_references(type)
    method_names = (type == :js ? JS_TAGS : CSS_TAGS)

    method_names.inject({}) do |results, method_name|
      grep(method_name).split("\n").each do |result| 
        file, script = result.split(":")
        script = script.scan(/'(.*)'/).flatten.first
        
        next if script.nil?

        results[file] = script
      end

      results
    end
  end
 end
	# These instance variables allow you to define which tags we should check
	# to find references to JavaScript and CSS files.
	#
	# Included first are the Rails defaults `javascript_include_tag` and
	# `stylesheet_link_tag`. Next are examples of custom methods we use at
	# Code School with the content_for method in order to include JS/CSS in
	# specific location such as the <head> tag in this instance.
	JS_TAGS = %w[ javascript_include_tag included_javascript_for_head ]
	CSS_TAGS = %w[ stylesheet_link_tag linked_stylesheet_for_head ]

	# This task will first run `git grep` to find any instance in your git repo
	# of the JS_TAGS and CSS_TAGS. It will then consult the Sprockets manifest and
	# check for matching logical paths for the files references by your JavaScript
	# and CSS tags. If the task can't find a mention of the assets you reference
	# in your tags within the Sprockets manifest, you will see them listed as
	# output. You should double-check that these references correspond to files
	# that are added to config.assets.precompile.
	#
	# It's likely that these files are not being properly precompiled which means
	# they're either going to 404 in production (if you have config.assets.compile
	# set to false) or cause a slow on-demand compilation (if you have
	# config.assets.compile set to true)
	namespace :assets do
	desc 'Check for non-precompiled assets'
	task :missing_precompile => :environment do
	javascripts = fetch_references(:js)
	stylesheets = fetch_references(:css)

	missing_js_precompiles = check_for_precompiled(javascripts)
	missing_css_precompiles = check_for_precompiled(stylesheets)

	if missing_js_precompiles.present?
	puts "Missing JavaScript precompiles: "
	puts missing_js_precompiles
	else
	puts "No missing JavaScript precompiles found."
	end

	if missing_css_precompiles.present?
	puts "Missing CSS precompiles: "
	puts missing_css_precompiles
	else
	puts "No missing CSS precompiles found."
	end
	end

	def sprockets_manifest_path
	Dir.glob("public/assets/.sprockets-manifest-*.json").first
	end

	def manifest
	if sprockets_manifest_path.present?
	JSON.parse File.read(sprockets_manifest_path)
	else
	raise "No Sprockets Manifest Found: you need to run `bundle exec rake assets:precompile` first."
	end
	end

	def logical_paths
	manifest["files"].map { \|script\| script.last["logical_path"] }
	end

	def check_for_precompiled(paths)
	paths.values.uniq.reject do \|script_path\|
	script_path.start_with?(*exclusion_prefixes) or
	logical_paths.any? { \|path\| path.include?(script_path) }
	end
	end

	def exclusion_prefixes
	# // means protocol-less file which means non-local
	%w[ // ]
	end

	def grep(method)
	%x{ git grep #{method} -- `git ls-files \| grep app/views` }
	end

	def fetch_references(type)
	method_names = (type == :js ? JS_TAGS : CSS_TAGS)

	method_names.inject({}) do \|results, method_name\|
	grep(method_name).split("\n").each do \|result\|
	file, script = result.split(":")
	script = script.scan(/'(.*)'/).flatten.first

	next if script.nil?

	results[file] = script
	end

	results
	end
	end
	end