# File lib/dnsruby/resource/DS.rb, line 109
      def digest_key(*args) # key, digest_type)
        digest_type = @digest_type
        key = args[0]
        if (args.length == 2)
            digest_type = args[1]
        end


        data = MessageEncoder.new {|msg|
           msg.put_name(key.name, true)
           key.encode_rdata(msg, true)
        }.to_s


        if (digest_type.code == 1)
            digestbin = OpenSSL::Digest::SHA1.digest(data)
            return digestbin
        elsif (digest_type.code == 2)
            digestbin = OpenSSL::Digest::SHA256.digest(data)
            return digestbin
        elsif (digest_type.code == 4)
            digestbin = OpenSSL::Digest::SHA384.digest(data)
            return digestbin
        end

      end