Class: Resolv::MDNS

Inherits:
DNS
  • Object
show all
Defined in:
lib/resolv.rb

Overview

Resolv::MDNS is a one-shot Multicast DNS (mDNS) resolver. It blindly makes queries to the mDNS addresses without understanding anything about multicast ports.

Information taken form the following places:

  • RFC 6762

Constant Summary collapse

Port =

Default mDNS Port

5353
AddressV4 =

Default IPv4 mDNS address

'224.0.0.251'
AddressV6 =

Default IPv6 mDNS address

'ff02::fb'
Addresses =

Default mDNS addresses

[
  [AddressV4, Port],
  [AddressV6, Port],
]

Constants inherited from DNS

DNS::RequestID, DNS::RequestIDMutex, DNS::UDPSize

Instance Method Summary collapse

Methods inherited from DNS

allocate_request_id, bind_random_port, #close, #each_name, #each_resource, #extract_resources, #fetch_resource, free_request_id, #getaddress, #getaddresses, #getname, #getnames, #getresource, #getresources, #lazy_initialize, #make_tcp_requester, open, random, rangerand, #timeouts=

Constructor Details

#initialize(config_info = nil) ⇒ MDNS

Creates a new one-shot Multicast DNS (mDNS) resolver.

config_info can be:

nil

Uses the default mDNS addresses

Hash

Must contain :nameserver or :nameserver_port like Resolv::DNS#initialize.


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# File 'lib/resolv.rb', line 2588

def initialize(config_info=nil)
  if config_info then
    super({ nameserver_port: Addresses }.merge(config_info))
  else
    super(nameserver_port: Addresses)
  end
end

Instance Method Details

#each_address(name) ⇒ Object

Iterates over all IP addresses for name retrieved from the mDNS resolver, provided name ends with “local”. If the name does not end in “local” no records will be returned.

name can be a Resolv::DNS::Name or a String. Retrieved addresses will be a Resolv::IPv4 or Resolv::IPv6


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# File 'lib/resolv.rb', line 2604

def each_address(name)
  name = Resolv::DNS::Name.create(name)

  return unless name.to_a.last == 'local'

  super(name)
end

#make_udp_requesterObject

:nodoc:


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# File 'lib/resolv.rb', line 2612

def make_udp_requester # :nodoc:
  nameserver_port = @config.nameserver_port
  Requester::MDNSOneShot.new(*nameserver_port)
end