MakeYourLaws/MakeYourLaws

require 'net/http'

# Modified from: http://joshuawood.net/validating-url-in-ruby-on-rails-3/
# Thanks Ilya! http://www.igvita.com/2006/09/07/validating-url-in-ruby-on-rails/
# Original credits: http://blog.inquirylabs.com/2006/04/13/simple-uri-validation/
# HTTP Codes: http://www.ruby-doc.org/stdlib/libdoc/net/http/rdoc/classes/Net/HTTPResponse.html

class UriValidator < ActiveModel::EachValidator
  def validate_each object, attribute, value
    # alternate format:
    # /(^(http|https):\/\/[a-z0-9]+([\-\.]{1}[a-z0-9]+)*\.[a-z]{2,5}(([0-9]{1,5})?\/.*)?$)/ix
    configuration = { nonresponse_message: 'is invalid or not responding',
      bad_format_message: 'does not appear to be a valid URI', nil_message: 'is not present',
      format: URI.regexp(%w(http https)), allow_nil: false }
    configuration.update(options)

    if value.nil?
      unless configuration[:allow_nil]
        object.errors.add(attribute, configuration[:nil_message]) && false
      end
    elsif value =~ configuration[:format]
      begin # check header response
        case Net::HTTP.get_response(URI.parse(value))
          when Net::HTTPSuccess then true
          when Net::HTTPRedirection then true # accept redirects too
          else object.errors.add(attribute, configuration[:nonresponse_message]) && false
        end
      rescue # Recover on DNS failures..
        object.errors.add(attribute, configuration[:nonresponse_message]) && false
      end
    else
      object.errors.add(attribute, configuration[:bad_format_message]) && false
    end
  end
end