Class: DNSSD::Reply::QueryRecord

Inherits:
DNSSD::Reply show all
Defined in:
lib/dnssd/reply/query_record.rb

Overview

Created by DNSSD::Service#query_record

Instance Attribute Summary collapse

Attributes inherited from DNSSD::Reply

#flags, #interface, #service

Instance Method Summary collapse

Methods inherited from DNSSD::Reply

#fullname, #interface_name, #protocol, #service_name, #set_fullname, #set_names

Constructor Details

#initialize(service, flags, interface, fullname, record_type, record_class, record, ttl) ⇒ QueryRecord

Creates a new QueryRecord, called internally by DNSSD::Service#query_record



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# File 'lib/dnssd/reply/query_record.rb', line 47

def initialize(service, flags, interface, fullname, record_type,
               record_class, record, ttl)
  super service, flags, interface

  set_fullname fullname

  @record_type = record_type
  @record_class = record_class
  @record = record

  @created = Time.now
  @ttl = ttl
end

Instance Attribute Details

#domain ⇒ Object (readonly)

A domain for registration or browsing



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# File 'lib/dnssd/reply/query_record.rb', line 11

def domain
  @domain
end

#name ⇒ Object (readonly)

The service name



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# File 'lib/dnssd/reply/query_record.rb', line 16

def name
  @name
end

#record ⇒ Object (readonly)

DNS Record data



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# File 'lib/dnssd/reply/query_record.rb', line 21

def record
  @record
end

#record_class ⇒ Object (readonly)

DNS Record class (only IN is supported)



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# File 'lib/dnssd/reply/query_record.rb', line 26

def record_class
  @record_class
end

#record_type ⇒ Object (readonly)

DNS Record type



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# File 'lib/dnssd/reply/query_record.rb', line 31

def record_type
  @record_type
end

#ttl ⇒ Object (readonly)

Time-to-live for this record. See #expired?



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# File 'lib/dnssd/reply/query_record.rb', line 36

def ttl
  @ttl
end

#type ⇒ Object (readonly)

The service type



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# File 'lib/dnssd/reply/query_record.rb', line 41

def type
  @type
end

Instance Method Details

#character_string_to_string(character_string) ⇒ Object

Converts a RFC 1035 character-string into a ruby String



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# File 'lib/dnssd/reply/query_record.rb', line 64

def character_string_to_string(character_string)
  length = character_string.slice 0
  length = length.ord unless Numeric === length
  string = character_string.slice 1, length

  if string.length != length then
    raise TypeError,
      "invalid character string, expected #{length} got #{string.length} in #{@record.inspect}"
  end

  string
end

#domain_name_to_string(domain_name) ⇒ Object

Converts a RFC 1035 domain-name into a ruby String



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# File 'lib/dnssd/reply/query_record.rb', line 80

def domain_name_to_string(domain_name)
  return '.' if domain_name == "\0"

  domain_name = domain_name.dup
  string = []

  until domain_name.empty? do
    string << character_string_to_string(domain_name)
    domain_name.slice! 0, string.last.length + 1
  end

  string << nil unless string.last.empty?

  string.join('.')
end

#expired? ⇒ Boolean

Has this QueryRecord passed its TTL?

Returns:

  • (Boolean) 


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# File 'lib/dnssd/reply/query_record.rb', line 99

def expired?
  Time.now > @created + ttl
end

#inspect ⇒ Object

:nodoc:



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# File 'lib/dnssd/reply/query_record.rb', line 103

def inspect # :nodoc:
  "#<%s:0x%x %s %s %s %p interface: %s flags: %p>" % [
    self.class, object_id,
    fullname, record_class_name, record_type_name, record,
    interface_name, @flags
  ]
end

#record_class_name ⇒ Object

Name of this record’s record_class



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# File 'lib/dnssd/reply/query_record.rb', line 114

def record_class_name
  return "unknown #{@record_class}" unless @record_class == DNSSD::Record::IN
  'IN' # Only IN is supported
end

#record_data ⇒ Object

Decodes output for #record, returning the raw record if it can’t be decoded. Handles:

A AAAA CNAME MX NS PTR SOA SRV TXT



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# File 'lib/dnssd/reply/query_record.rb', line 125

def record_data
  return @record unless @record_class == DNSSD::Record::IN

  case @record_type
  when DNSSD::Record::A,
       DNSSD::Record::AAAA then
    IPAddr.new_ntoh @record
  when DNSSD::Record::CNAME,
       DNSSD::Record::NS,
       DNSSD::Record::PTR then
    domain_name_to_string @record
  when DNSSD::Record::MX then
    mx = @record.unpack 'nZ*'
    mx[-1] = domain_name_to_string mx.last
    mx
  when DNSSD::Record::SOA then
    soa = @record.unpack 'Z*Z*NNNNN'
    soa[0] = domain_name_to_string soa[0]
    soa[1] = domain_name_to_string soa[1]
    soa
  when DNSSD::Record::SRV then
    srv = @record.unpack 'nnnZ*'
    srv[-1] = domain_name_to_string srv.last
    srv
  when DNSSD::Record::TXT then
    record = @record.dup
    txt = []

    until record.empty? do
      txt << character_string_to_string(record)
      record.slice! 0, txt.last.length + 1
    end

    txt
  else
    @record
  end
end

#record_type_name ⇒ Object

Name of this record’s record_type



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# File 'lib/dnssd/reply/query_record.rb', line 167

def record_type_name
  return "unknown #{@record_type} for record class (#{@record_class})" unless
    @record_class == DNSSD::Record::IN
  DNSSD::Record::VALUE_TO_NAME[@record_type]
end

#to_s ⇒ Object

Outputs this record in a BIND-like DNS format



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# File 'lib/dnssd/reply/query_record.rb', line 176

def to_s
  "%s %d %s %s %p" % [
    fullname, ttl, record_class_name, record_type_name, record_data
  ]
end