Module: Celluloid::DNS::System

Defined in:
lib/celluloid/dns/system.rb

Overview

This module encapsulates system dependent name lookup functionality.

Defined Under Namespace

Classes: Hosts

Constant Summary collapse

RESOLV_CONF = 
"/etc/resolv.conf"
HOSTS = 
"/etc/hosts"

Class Method Summary collapse

Class Method Details

.hosts_path ⇒ Object 



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# File 'lib/celluloid/dns/system.rb', line 33

def self.hosts_path
  if RUBY_PLATFORM =~ /mswin32|mingw|bccwin/
    Win32::Resolv.get_hosts_path
  else
    HOSTS
  end
end

.nameservers ⇒ Object

Get a list of standard nameserver connections which can be used for querying any standard servers that the system has been configured with. There is no equivalent facility to use the ‘hosts` file at present.



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# File 'lib/celluloid/dns/system.rb', line 134

def self.nameservers
  nameservers = []

  if File.exist? RESOLV_CONF
    nameservers = parse_resolv_configuration(RESOLV_CONF)
  elsif defined?(Win32::Resolv) and RUBY_PLATFORM =~ /mswin32|cygwin|mingw|bccwin/
    search, nameservers = Win32::Resolv.get_resolv_info
  end

  return standard_connections(nameservers)
end

.parse_resolv_configuration(path) ⇒ Object 



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# File 'lib/celluloid/dns/system.rb', line 102

def self.parse_resolv_configuration(path)
  nameservers = []
  File.open(path) do |file|
    file.each do |line|
      # Remove any comments:
      line.sub!(/[#;].*/, '')

      # Extract resolv.conf command:
      keyword, *args = line.split(/\s+/)

      case keyword
      when 'nameserver'
        nameservers += args
      end
    end
  end

  return nameservers
end

.standard_connections(nameservers) ⇒ Object 



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# File 'lib/celluloid/dns/system.rb', line 122

def self.standard_connections(nameservers)
  connections = []

  nameservers.each do |host|
    connections << [:udp, host, 53]
    connections << [:tcp, host, 53]
  end

  return connections
end