# File lib/aws/sns/message.rb, line 168
      def download url
        raise MessageWasNotAuthenticError, "cert is not hosted at AWS URL (https): #{url}" unless url =~ /^https.*amazonaws\.com\/.*$/i
        tries = 0
        begin
          resp = https_get(url)
          resp.body
        rescue => error
          tries += 1
          retry if tries < 3
          raise error
        end
      end