Source Code for Module dns.rdtypes.nsbase

 1  # Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license 
 2   
 3  # Copyright (C) 2003-2007, 2009-2011 Nominum, Inc. 
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17   
18  """NS-like base classes.""" 
19   
20  from io import BytesIO 
21   
22  import dns.exception 
23  import dns.rdata 
24  import dns.name 
25   
26   
27 -class NSBase(dns.rdata.Rdata): 
28   
29      """Base class for rdata that is like an NS record. 
30   
31      @ivar target: the target name of the rdata 
32      @type target: dns.name.Name object""" 
33   
34      __slots__ = ['target'] 
35   
36 -    def __init__(self, rdclass, rdtype, target): 
37          super(NSBase, self).__init__(rdclass, rdtype) 
38          self.target = target 
39   
40 -    def to_text(self, origin=None, relativize=True, **kw): 
41          target = self.target.choose_relativity(origin, relativize) 
42          return str(target) 
43   
44      @classmethod 
45 -    def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True): 
46          target = tok.get_name() 
47          target = target.choose_relativity(origin, relativize) 
48          tok.get_eol() 
49          return cls(rdclass, rdtype, target) 
50   
51 -    def to_wire(self, file, compress=None, origin=None): 
52          self.target.to_wire(file, compress, origin) 
53   
54 -    def to_digestable(self, origin=None): 
55          return self.target.to_digestable(origin) 
56   
57      @classmethod 
58 -    def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin=None): 
59          (target, cused) = dns.name.from_wire(wire[: current + rdlen], 
60                                               current) 
61          if cused != rdlen: 
62              raise dns.exception.FormError 
63          if origin is not None: 
64              target = target.relativize(origin) 
65          return cls(rdclass, rdtype, target) 
66   
67 -    def choose_relativity(self, origin=None, relativize=True): 
68          self.target = self.target.choose_relativity(origin, relativize) 
69   
70   
71 -class UncompressedNS(NSBase): 
72   
73      """Base class for rdata that is like an NS record, but whose name 
74      is not compressed when convert to DNS wire format, and whose 
75      digestable form is not downcased.""" 
76   
77 -    def to_wire(self, file, compress=None, origin=None): 
78          super(UncompressedNS, self).to_wire(file, None, origin) 
79   
80 -    def to_digestable(self, origin=None): 
81          f = BytesIO() 
82          self.to_wire(f, None, origin) 
83          return f.getvalue() 
84