From: Daniel Hobe <daniel@...>
Date: 2003-12-17T15:37:07+09:00
Subject: Re: resolv.rb question

Daniel Hobe wrote:
> I'm writing a script where it would be really good to be able to give
> Resolv::DNS.new() an arbitrary list of DNS servers to use without having
> to feed it a modified resolv.conf file.  Is there a good way to do this?
> 
> I'd like to be able to do this:
> r =
> Resolv::DNS.new(nameservers=['127.0.0.1','192.168.0.1'],search=['foo.com'])
> a = r.getaddress($host)
> 
> Is there a good way to do this?  The current Resolv::DNS seems to be
> fixated on loading all it's information from a resolv.conf or hosts file.
> 

I solved my own question thusly:

#!/usr/bin/env ruby

require 'resolv'
Thread.abort_on_exception = true

class Resolv::DNS2 < Resolv::DNS
   def initialize(nameserver=['localhost'],search = nil,ndots=1)
     @mutex = Mutex.new
     @config = Config.new(nameserver,search,ndots)
     @initialized = nil
   end

   class Config < Resolv::DNS::Config
     def initialize(nameserver,search,ndots)
       @mutex = Mutex.new
       @nameserver = nameserver
       @search = search
       @ndots = ndots
       @initialized = nil
     end

     def lazy_initialize
       unless @search
         hostname = Socket.gethostname
         if /\./ =~ hostname
           @search = [Resolv::DNS::Label.split($')]
         else
           @search = [[]]
         end
       end
     end

   end
end

d = Resolv::DNS2.new(['216.220.40.243','205.210.42.20'],
                      [['packetspike.net'],['nightrunner.com']])
puts d.getaddress('www.packetspike.net')

-- 
Daniel Hobe <daniel@nightrunner.com>
http://www.nightrunner.com