Class DnsUpdateWriter

  • All Implemented Interfaces:
    DnsWriter

    public class DnsUpdateWriter
    extends BaseDnsWriter
    A DnsWriter that implements the DNS UPDATE protocol as specified in RFC 2136. Publishes changes in the domain-registry to a (capable) external DNS server, sometimes called a "hidden master". DNS UPDATE messages are sent via a supplied "transport" class. On call to BaseDnsWriter.commit(), a single UPDATE message is created containing the records required to "synchronize" the DNS with the current (at the time of processing) state of the registry, for the supplied domain/host.

    The general strategy of the publish methods is to delete all resource records of any type that match the exact domain/host name supplied. And then for create/update cases, add any required records. Deleting all records of any type assumes that the registry is authoritative for all records for names in the zone. This seems appropriate for a TLD DNS server, which should only contain records required for proper DNS delegation.

    Only NS, DS, A, and AAAA records are published, and in particular no DNSSEC signing is done assuming that this will be done by a third party DNS provider.

    Each commit call is treated as an atomic update to the DNS. If a commit fails an exception is thrown. The SOA record serial number is implicitly incremented by the server on each UPDATE message, as required by RFC 2136. Care must be taken to make sure the SOA serial number does not go backwards if the entire TLD (zone) is "reset" to empty and republished.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.lang.String NAME
      The name of the pricing engine, as used in Registry.dnsWriter.
    • Constructor Summary

      Constructors 
      Constructor Description
      DnsUpdateWriter​(java.lang.String zoneName, org.joda.time.Duration dnsDefaultATtl, org.joda.time.Duration dnsDefaultNsTtl, org.joda.time.Duration dnsDefaultDsTtl, DnsMessageTransport transport, Clock clock)
      Class constructor.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected void commitUnchecked()
      Commits DNS updates.
      void publishDomain​(java.lang.String domainName)
      Loads domainName from the database and publishes its NS/DS records to the DNS server.
      void publishHost​(java.lang.String hostName)
      Loads hostName from the database and publishes its A/AAAA glue records to the DNS server, if it is used as an in-bailiwick nameserver.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • NAME

        public static final java.lang.String NAME
        The name of the pricing engine, as used in Registry.dnsWriter. Remember to change the value on affected Registry objects to prevent runtime failures.
        See Also:
        Constant Field Values
    • Constructor Detail

      • DnsUpdateWriter

        @Inject
        public DnsUpdateWriter​(@DnsWriterZone
                               java.lang.String zoneName,
                               @Config("dnsDefaultATtl")
                               org.joda.time.Duration dnsDefaultATtl,
                               @Config("dnsDefaultNsTtl")
                               org.joda.time.Duration dnsDefaultNsTtl,
                               @Config("dnsDefaultDsTtl")
                               org.joda.time.Duration dnsDefaultDsTtl,
                               DnsMessageTransport transport,
                               Clock clock)
        Class constructor.
        Parameters:
        dnsDefaultATtl - TTL used for any created resource records
        dnsDefaultNsTtl - TTL used for any created nameserver records
        dnsDefaultDsTtl - TTL used for any created DS records
        transport - the transport used to send/receive the UPDATE messages
        clock - a source of time
    • Method Detail

      • publishDomain

        public void publishDomain​(java.lang.String domainName)
        Description copied from interface: DnsWriter
        Loads domainName from the database and publishes its NS/DS records to the DNS server. Replaces existing records for the exact name supplied with an NS record for each name server and a DS record for each delegation signer stored in the registry for the supplied domain name. If the domain is deleted or is in a "non-publish" state then any existing records are deleted.

        This must NOT actually perform any action, instead it should stage the action so that it's performed when DnsWriter.commit() is called.

        Parameters:
        domainName - the fully qualified domain name, with no trailing dot
      • publishHost

        public void publishHost​(java.lang.String hostName)
        Description copied from interface: DnsWriter
        Loads hostName from the database and publishes its A/AAAA glue records to the DNS server, if it is used as an in-bailiwick nameserver. Orphaned glue records are prohibited. Replaces existing records for the exact name supplied, with an A or AAAA record (as appropriate) for each address stored in the registry, for the supplied host name. If the host is deleted then the existing records are deleted. Assumes that this method will only be called for in-bailiwick hosts. The registry does not have addresses for other hosts.

        This must NOT actually perform any action, instead it should stage the action so that it's performed when DnsWriter.commit() is called.

        Parameters:
        hostName - the fully qualified host name, with no trailing dot
      • commitUnchecked

        protected void commitUnchecked()
        Description copied from class: BaseDnsWriter
        Commits DNS updates. This can never be called more than once.
        Specified by:
        commitUnchecked in class BaseDnsWriter