Net::DNS::Resolver::Programmable(3)			User Contributed Perl Documentation		       Net::DNS::Resolver::Programmable(3)

NAME

       Net::DNS::Resolver::Programmable - programmable DNS resolver class for offline emulation of DNS

VERSION

       0.003

SYNOPSIS

	   use Net::DNS::Resolver::Programmable;
	   use Net::DNS::RR;

	   my $resolver = Net::DNS::Resolver::Programmable->new(
	       records	       => {
		   'example.com'     => [
		       Net::DNS::RR->new('example.com.	   NS  ns.example.org.'),
		       Net::DNS::RR->new('example.com.	   A   192.168.0.1')
		   ],
		   'ns.example.org'  => [
		       Net::DNS::RR->new('ns.example.org.  A   192.168.1.1')
		   ]
	       },

	       resolver_code   => sub {
		   my ($domain, $rr_type, $class) = @_;
		   ...
		   return ($result, $aa, @rrs);
	       }
	   );

DESCRIPTION

       Net::DNS::Resolver::Programmable is a Net::DNS::Resolver descendant class that allows a virtual DNS to be emulated instead of querying the
       real DNS.  A set of static DNS records may be supplied, or arbitrary code may be specified as a means for retrieving DNS records, or even
       generating them on the fly.

   Constructor
       The following constructor is provided:

       new(%options): returns Net::DNS::Resolver::Programmable
	   Creates a new programmed DNS resolver object.

	   %options is a list of key/value pairs representing any of the following options:

	   records
	       A reference to a hash of arrays containing a static set of Net::DNS::RR objects.  The hash entries must be indexed by fully
	       qualified domain names (lower-case, without any trailing dots), and the entries themselves must be arrays of the RR objects
	       pertaining to these domain names.  For example:

		   records => {
		       'example.com'	 => [
			   Net::DNS::RR->new('example.com.     NS  ns.example.org.'),
			   Net::DNS::RR->new('example.com.     A   192.168.0.1')
		       ],
		       'www.example.com' => [
			   Net::DNS::RR->new('www.example.com. A   192.168.0.2')
		       ],
		       'ns.example.org'  => [
			   Net::DNS::RR->new('ns.example.org.  A   192.168.1.1')
		       ]
		   }

	       If this option is specified, the resolver retrieves requested RRs from this data structure.

	   resolver_code
	       A code reference used as a call-back for dynamically retrieving requested RRs.

	       The code must take the following query parameters as arguments: the domain, RR type, and class.

	       It must return a list composed of: the response's RCODE (by name, as returned by Net::DNS::Header->rcode), the "aa" (authoritative
	       answer) flag (boolean, use undef if you don't care), and the Net::DNS::RR answer objects.  If an error string is returned instead
	       of a valid RCODE, a Net::DNS::Packet object is not constructed but an error condition for the resolver is signaled instead.

	       For example:

		   resolver_code => sub {
		       my ($domain, $rr_type, $class) = @_;
		       ...
		       return ($result, $aa, @rrs);
		   }

	       If both this and the "records" option are specified, then statically programmed records are used in addition to any that are
	       returned by the configured resolver code.

	   defnames
	   dnsrch
	   domain
	   searchlist
	   debug
	       These Net::DNS::Resolver options are also meaningful with Net::DNS::Resolver::Programmable.  See Net::DNS::Resolver for their
	       descriptions.

   Instance methods
       The following instance methods of Net::DNS::Resolver are also supported by Net::DNS::Resolver::Programmable:

       search: returns Net::DNS::Packet
       query: returns Net::DNS::Packet
       send: returns Net::DNS::Packet
	   Performs an offline DNS query, using the statically programmed DNS RRs and/or the configured dynamic resolver code.	See the "new"
	   constructor's "records" and "resolver_code" options.  See the descriptions of search, query, and send for details about the calling
	   syntax of these methods.

       print
       string: returns string
       searchlist: returns list of string
       defnames: returns boolean
       dnsrch: returns boolean
       debug: returns boolean
       errorstring: returns string
       answerfrom: returns string
       answersize: returns integer
	   See "METHODS" in Net::DNS::Resolver.

       Currently the following methods of Net::DNS::Resolver are not supported: axfr, axfr_start, axfr_next, nameservers, port, srcport, srcaddr,
       bgsend, bgread, bgisready, tsig, retrans, retry, recurse, usevc, tcp_timeout, udp_timeout, persistent_tcp, persistent_udp, igntc, dnssec,
       cdflag, udppacketsize.  The effects of using these on Net::DNS::Resolver::Programmable objects are undefined.

SEE ALSO

       Net::DNS::Resolver

       For availability, support, and license information, see the README file included with Net::DNS::Resolver::Programmable.

AUTHORS

       Julian Mehnle <julian@mehnle.net>

perl v5.18.2							    2017-10-06				       Net::DNS::Resolver::Programmable(3)