Source Code for Module dns.rdtypes.nsbase

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15   
16  """NS-like base classes.""" 
17   
18  from io import BytesIO 
19   
20  import dns.exception 
21  import dns.rdata 
22  import dns.name 
23   
24   
25 -class NSBase(dns.rdata.Rdata): 
26   
27      """Base class for rdata that is like an NS record. 
28   
29      @ivar target: the target name of the rdata 
30      @type target: dns.name.Name object""" 
31   
32      __slots__ = ['target'] 
33   
34 -    def __init__(self, rdclass, rdtype, target): 
35          super(NSBase, self).__init__(rdclass, rdtype) 
36          self.target = target 
37   
38 -    def to_text(self, origin=None, relativize=True, **kw): 
39          target = self.target.choose_relativity(origin, relativize) 
40          return str(target) 
41   
42      @classmethod 
43 -    def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True): 
44          target = tok.get_name() 
45          target = target.choose_relativity(origin, relativize) 
46          tok.get_eol() 
47          return cls(rdclass, rdtype, target) 
48   
49 -    def to_wire(self, file, compress=None, origin=None): 
50          self.target.to_wire(file, compress, origin) 
51   
52 -    def to_digestable(self, origin=None): 
53          return self.target.to_digestable(origin) 
54   
55      @classmethod 
56 -    def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin=None): 
57          (target, cused) = dns.name.from_wire(wire[: current + rdlen], 
58                                               current) 
59          if cused != rdlen: 
60              raise dns.exception.FormError 
61          if origin is not None: 
62              target = target.relativize(origin) 
63          return cls(rdclass, rdtype, target) 
64   
65 -    def choose_relativity(self, origin=None, relativize=True): 
66          self.target = self.target.choose_relativity(origin, relativize) 
67   
68   
69 -class UncompressedNS(NSBase): 
70   
71      """Base class for rdata that is like an NS record, but whose name 
72      is not compressed when convert to DNS wire format, and whose 
73      digestable form is not downcased.""" 
74   
75 -    def to_wire(self, file, compress=None, origin=None): 
76          super(UncompressedNS, self).to_wire(file, None, origin) 
77   
78 -    def to_digestable(self, origin=None): 
79          f = BytesIO() 
80          self.to_wire(f, None, origin) 
81          return f.getvalue() 
82