Class: Net::DNS::RR::Classes

Inherits:
Object
  • Object
show all
Defined in:
lib/net/dns/rr/classes.rb

Overview

This is an auxiliary class to hadle RR class field in a DNS packet.

Constant Summary collapse

Classes =

An hash with the values of each RR class stored with the respective id number

{
  'IN'        => 1,       # RFC 1035
  'CH'        => 3,       # RFC 1035
  'HS'        => 4,       # RFC 1035
  'NONE'      => 254,     # RFC 2136
  'ANY'       => 255,     # RFC 1035
}
@@default =

The default value when class is nil in Resource Records

Classes["IN"]

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(cls) ⇒ Classes

Creates a new object representing an RR class. Performs some checks on the argument validity too. Il cls is nil, the default value is ANY or the one set with Classes.default=



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# File 'lib/net/dns/rr/classes.rb', line 70

def initialize(cls)
  case cls
  when String
    # type in the form "A" or "NS"
    new_from_string(cls.upcase) 
  when Fixnum
    # type in numeric form
    new_from_num(cls) 
  when nil
    # default type, control with Classes.default=
    @str = Classes.invert[@@default] 
    @num = @@default
  else
    raise ClassArgumentError, "Wrong cls class: #{cls.class}"
  end
end

Class Method Details

.default=(str) ⇒ Object

Be able to control the default class to assign when cls argument is nil. Default to IN



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# File 'lib/net/dns/rr/classes.rb', line 26

def self.default=(str)
  if Classes.has_key? str
    @@default = Classes[str]
  else
    raise ClassArgumentError, "Unknown class #{str}"
  end
end

.regexp ⇒ Object

Gives in output the keys from the Classes hash in a format suited for regexps



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# File 'lib/net/dns/rr/classes.rb', line 63

def self.regexp
  Classes.keys.join("|")
end

.to_str(cls) ⇒ Object

Returns the class in string format, as “IN” or “CH”, given the numeric value



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# File 'lib/net/dns/rr/classes.rb', line 48

def self.to_str(cls)
  case cls
  when Fixnum
    if Classes.invert.has_key? cls
      return Classes.invert[cls]
    else
      raise ClassArgumentError, "Unknown class number #{cls}"
    end
  else
    raise ClassArgumentError, "Wrong cls class: #{cls.class}"
  end
end

.valid?(cls) ⇒ Boolean

Checks whether cls is a valid RR class.

Returns:

  • (Boolean) 


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# File 'lib/net/dns/rr/classes.rb', line 35

def self.valid?(cls)
  case cls
  when String
    return Classes.has_key?(cls)
  when Fixnum
    return Classes.invert.has_key?(cls)
  else
    raise ClassArgumentError, "Wrong cls class: #{cls.class}"
  end
end

Instance Method Details

#inspect ⇒ Object

Returns the class in number format (default for normal use)



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# File 'lib/net/dns/rr/classes.rb', line 117

def inspect
  @num
end

#to_i ⇒ Object

Returns the class in numeric format, usable by the pack methods for data transfers



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# File 'lib/net/dns/rr/classes.rb', line 129

def to_i
  @num.to_i
end

#to_s ⇒ Object

Returns the class in string format, i.d. “IN” or “CH” or such a string.



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# File 'lib/net/dns/rr/classes.rb', line 123

def to_s
  @str
end

#to_str ⇒ Object

Should be used only for testing purpouses



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# File 'lib/net/dns/rr/classes.rb', line 135

def to_str
  @num.to_s
end