Package org.ldaptive

Class DnsSrvConnectionStrategy

java.lang.Object
org.ldaptive.AbstractFreezable
org.ldaptive.AbstractConnectionStrategy
org.ldaptive.DnsSrvConnectionStrategy
All Implemented Interfaces:
Iterable<LdapURL>, ConnectionStrategy, Freezable
public class DnsSrvConnectionStrategy extends AbstractConnectionStrategy
DNS SRV connection strategy. Queries a DNS server for SRV records and uses those records to construct a list of URLs. A time to live can be set to control how often the DNS server is consulted. See http://www.ietf.org/rfc/rfc2782.txt.

  • Field Details

    • DEFAULT_TTL

      protected static final Duration DEFAULT_TTL
      Default time to live for DNS results.

    • dnsContextFactory

      private final DNSContextFactory dnsContextFactory
      DNS context factory to override initialization parameters.

    • srvTtl

      private final Duration srvTtl
      Time to live for SRV records.

    • useSSL

      private final boolean useSSL
      Connect to LDAP using LDAPS.

    • ldapUrls

      private String ldapUrls
      LDAP URL string used to initialize this strategy.

    • dnsResolvers

      private Map<SRVDNSResolver,String> dnsResolvers
      Resolver(s) for SRV DNS records.

    • expirationTime

      private Instant expirationTime
      SRV records expiration time.

  • Constructor Details

    • DnsSrvConnectionStrategy

      public DnsSrvConnectionStrategy()
      Default constructor.

    • DnsSrvConnectionStrategy

      public DnsSrvConnectionStrategy(Duration ttl)
      Creates a new DNS SRV connection strategy.
      Parameters:
      ttl - time to live for SRV records

    • DnsSrvConnectionStrategy

      public DnsSrvConnectionStrategy(DNSContextFactory factory)
      Creates a new DNS SRV connection strategy.
      Parameters:
      factory - DNS context factory

    • DnsSrvConnectionStrategy

      public DnsSrvConnectionStrategy(DNSContextFactory factory, Duration ttl)
      Creates a new DNS SRV connection strategy.
      Parameters:
      factory - DNS context factory
      ttl - time to live for SRV records

    • DnsSrvConnectionStrategy

      public DnsSrvConnectionStrategy(DNSContextFactory factory, Duration ttl, boolean ssl)
      Creates a new DNS SRV connection strategy.
      Parameters:
      factory - DNS context factory
      ttl - time to live for SRV records
      ssl - whether SRV records should produce LDAPS URLs

  • Method Details

    • populate

      public void populate(String urls, LdapURLSet urlSet)
      Description copied from interface: ConnectionStrategy
      Populates a LdapURLSet from the URL string provided at configuration time.
      Specified by:
      populate in interface ConnectionStrategy
      Overrides:
      populate in class AbstractConnectionStrategy
      Parameters:
      urls - Space-delimited string of URLs describing the LDAP hosts to connect to. The URLs in the string are commonly ldap:// or ldaps:// URLs that directly describe the hosts to connect to, but may also describe a resource from which to obtain LDAP connection URLs as is the case for DnsSrvConnectionStrategy that use URLs with the scheme dns:.
      urlSet - LDAP URL set to populate.

    • readSrvRecords

      protected Set<SRVRecord> readSrvRecords(String urls)
      Parses the supplied DNS URL string and reads SRV records from DNS.
      Parameters:
      urls - to parse
      Returns:
      Set of DNS SRV records ordered first by priority and then by weight.

    • parseUrl

      protected String[] parseUrl(String url)
      Parses the supplied URL. If the URL has an ldap scheme, it is inspected for a baseDN which will be used as the domain. Otherwise, the URL is assumed to have a dns scheme.
      Parameters:
      url - to parse
      Returns:
      array containing the DNS URL and the record name in that order

    • parseDnsUrl

      protected String[] parseDnsUrl(String url)
      Parses a DNS URL of the form dns://hostname/domain?record. Where record is the DNS record to retrieve.
      Parameters:
      url - to parse
      Returns:
      array containing the DNS URL and the record name in that order

    • iterator

      public Iterator<LdapURL> iterator()
      Returns a list of URLs retrieved from DNS SRV records.
      Returns:
      list of URLs to attempt connections to

    • retrieveDNSRecords

      protected Set<SRVRecord> retrieveDNSRecords()
      Invoke DNSResolver.resolve(String) for each resolver until results are found.
      Returns:
      set of LDAP URLs

    • newInstance

      public DnsSrvConnectionStrategy newInstance()
      Description copied from interface: ConnectionStrategy
      Create a deep copy of this strategy.
      Returns:
      new instance of this connection strategy