Source Code for Module dns.rdtypes.nsbase

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15   
16  """NS-like base classes.""" 
17   
18  import cStringIO 
19   
20  import dns.exception 
21  import dns.rdata 
22  import dns.name 
23   
24 -class NSBase(dns.rdata.Rdata): 
25      """Base class for rdata that is like an NS record. 
26   
27      @ivar target: the target name of the rdata 
28      @type target: dns.name.Name object""" 
29   
30      __slots__ = ['target'] 
31   
32 -    def __init__(self, rdclass, rdtype, target): 
33          super(NSBase, self).__init__(rdclass, rdtype) 
34          self.target = target 
35   
36 -    def to_text(self, origin=None, relativize=True, **kw): 
37          target = self.target.choose_relativity(origin, relativize) 
38          return str(target) 
39   
40 -    def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True): 
41          target = tok.get_name() 
42          target = target.choose_relativity(origin, relativize) 
43          tok.get_eol() 
44          return cls(rdclass, rdtype, target) 
45   
46      from_text = classmethod(from_text) 
47   
48 -    def to_wire(self, file, compress = None, origin = None): 
49          self.target.to_wire(file, compress, origin) 
50   
51 -    def to_digestable(self, origin = None): 
52          return self.target.to_digestable(origin) 
53   
54 -    def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None): 
55          (target, cused) = dns.name.from_wire(wire[: current + rdlen], 
56                                               current) 
57          if cused != rdlen: 
58              raise dns.exception.FormError 
59          if not origin is None: 
60              target = target.relativize(origin) 
61          return cls(rdclass, rdtype, target) 
62   
63      from_wire = classmethod(from_wire) 
64   
65 -    def choose_relativity(self, origin = None, relativize = True): 
66          self.target = self.target.choose_relativity(origin, relativize) 
67   
68 -class UncompressedNS(NSBase): 
69      """Base class for rdata that is like an NS record, but whose name 
70      is not compressed when convert to DNS wire format, and whose 
71      digestable form is not downcased.""" 
72   
73 -    def to_wire(self, file, compress = None, origin = None): 
74          super(UncompressedNS, self).to_wire(file, None, origin) 
75   
76 -    def to_digestable(self, origin = None): 
77          f = cStringIO.StringIO() 
78          self.to_wire(f, None, origin) 
79          return f.getvalue() 
80