rails paperclip disable validation

1, Disable from global config file: config/application.rb

require 'paperclip/media_type_spoof_detector'
module Paperclip
  class MediaTypeSpoofDetector
    def spoofed?
      false
    end
  end
end

2, Disable from controller
class Logserver < ActiveRecord::Base
  has_attached_file :serverkey, :path => "public/keys/:id/:filename", :url => "/keys/:id/:basename.:extension"
  #validates_attachment_content_type :serverkey, :content_type => /\Atext.*\Z/
  do_not_validate_attachment_file_type :serverkey
 end