Rake middleware to bounce off mobile devices and bots

restrict.rb

module Rack
  class Restrict
    REGEX_MOBILE = /(blackberry|motorokr|motorola|sony|windows ce|240x320|176x220|palm|mobile|iphone|ipod|symbian|nokia|samsung|midp)/i
    REGEX_BOTS = /(google|yahoo|baidu|bot|webalta|ia_archiver)/
    
    attr_reader :options
    
    def initialize(app)
      @app = app
    end
    
    def call(env)
      str = env['HTTP_USER_AGENT']
      restrict = !str.match(REGEX_MOBILE).nil? || !str.match(REGEX_BOTS).nil?
      restrict ? forbidden! : @app.call(env)
    end
      
    def forbidden!
      [403, { 'Content-Type' => 'text/html', 'Content-Length' => '0' }, []]
    end
  end
end