GSP
Quick Navigator

Search Site

Unix VPS
A - Starter
B - Basic
C - Preferred
D - Commercial
MPS - Dedicated
Previous VPSs
* Sign Up! *

Support
Contact Us
Online Help
Handbooks
Domain Status
Man Pages

FAQ
Virtual Servers
Pricing
Billing
Technical

Network
Facilities
Connectivity
Topology Map

Miscellaneous
Server Agreement
Year 2038
Credits
 

USA Flag

 

 

Man Pages


Manual Reference Pages  -  POE::COMPONENT::CLIENT::DNS::RECURSIVE (3)

.ds Aq ’

NAME

POE::Component::Client::DNS::Recursive - A recursive DNS client for POE

CONTENTS

VERSION

version 1.08

SYNOPSIS



  use strict;
  use warnings;
  use Getopt::Long;

  use POE qw(Component::Client::DNS::Recursive);

  my $trace;
  GetOptions (trace => \$trace);

  my $host = shift || die "Nothing to query\n";
  my $type = shift;

  POE::Session->create(
    package_states => [
          main, [qw(_start _response _trace)],
    ],
  );

  $poe_kernel->run();
  exit 0;

  sub _start {
    POE::Component::Client::DNS::Recursive->resolve(
          event => _response,
          host => $host,
        ( $type ? ( type => $type ) : () ),
        ( $trace ? ( trace => $_[SESSION]->postback( _trace ) ) : () ),
    );
    return;
  }

  sub _trace {
    my $packet = $_[ARG1]->[0];
    return unless $packet;
    print $packet->string;
    return;
  }

  sub _response {
    my $packet = $_[ARG0]->{response};
    return unless $packet;
    print $packet->string;
    return;
  }



DESCRIPTION

POE::Component::Client::DNS::Recursive is a POE component that implements a recursive DNS client.

POE sessions and components can spawn a POE::Component::Client::DNS::Recursive instance to perform a DNS query. The component will perform its task and return the results to the requesting session.

One may also enable tracing of the delegation path from the root name servers for the name being looked up.

CONSTRUCTOR

resolve Takes a number of options, only those marked as mandatory are required:



  event, the event to emit when completed, mandatory;
  host, what to look up, mandatory;
  type, defaults to A or PTR if host appears to be an IP address;
  class, defaults to IN;
  port, the port to use for DNS requests. Default is 53;
  session, provide an alternative session to send the resultant event to;
  trace, the event to send trace information to;
  nameservers, an arrayref of IP addresses that the poco will use instead of built-in hints;
  context, user defined data. Can be anything that can be stored in a scalar;



event and trace are discussed in the OUTPUT EVENTS section below.

event and trace may also be POE::Session postbacks.

session is only required if one wishes to send the resultant events to a different session than the calling one, or if the component is spawned with the POE::Kernel as its parent.

OUTPUT EVENTS

The output events from the component as specified in the resolve constructor.

If you have opted to use postbacks, then these parameters will be passed in the arrayref in ARG1.
event Emitted when the query has finished.

ARG0 will contain a hashref with the following fields:



  host     => the host requested,
  type     => the type requested,
  class    => the class requested,
  context  => the context that was passed to us,
  response => a Net::DNS::Packet object,
  error    => an error message ( if applicable )



response contains a Net::DNS::Packet object on success or undef if the lookup failed. The Net::DNS::Packet object describes the response to the program’s request. It may contain several DNS records. Please consult Net::DNS and Net::DNS::Packet for more information.

error contains a description of any error that has occurred. It is only valid if response is undefined.

trace Emitted whenever an element of the delegation path from the root servers is found.

ARG0 will be a Net::DNS::Packet object.

SEE ALSO

POE::Component::Client::DNS

Perl Programming

AUTHOR

Chris Williams <chris@bingosnet.co.uk>

COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by Chris Williams.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

Search for    or go to Top of page |  Section 3 |  Main Index


perl v5.20.3 POE::COMPONENT::CLIENT::DNS::RECURSIVE (3) 2014-06-03

Powered by GSP Visit the GSP FreeBSD Man Page Interface.
Output converted with manServer 1.07.