Nanoc Juicer filter for minifying CSS/JS

juicer_filter.rb

module PK
  module Filter

    class Juice < Nanoc3::Filter
      identifier :juice
      type       :text

      def run(content, params={})
        input_filename = File.join('content', @item.path)
        output_filename = File.absolute_path(File.join('tmp', "#{@item.path}"))
        system('juicer', 'merge', '--force', '-o', output_filename, input_filename)
        minified = File.open(output_filename, 'r') { |f| f.read }
      end
    end

  end
end