Source Code for Module dns.namedict

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15   
16  """DNS name dictionary""" 
17   
18  import dns.name 
19   
20 -class NameDict(dict): 
21   
22      """A dictionary whose keys are dns.name.Name objects. 
23      @ivar max_depth: the maximum depth of the keys that have ever been 
24      added to the dictionary. 
25      @type max_depth: int 
26      """ 
27   
28 -    def __init__(self, *args, **kwargs): 
29          super(NameDict, self).__init__(*args, **kwargs) 
30          self.max_depth = 0 
31   
32 -    def __setitem__(self, key, value): 
33          if not isinstance(key, dns.name.Name): 
34              raise ValueError('NameDict key must be a name') 
35          depth = len(key) 
36          if depth > self.max_depth: 
37              self.max_depth = depth 
38          super(NameDict, self).__setitem__(key, value) 
39   
40 -    def get_deepest_match(self, name): 
41          """Find the deepest match to I{name} in the dictionary. 
42   
43          The deepest match is the longest name in the dictionary which is 
44          a superdomain of I{name}. 
45   
46          @param name: the name 
47          @type name: dns.name.Name object 
48          @rtype: (key, value) tuple 
49          """ 
50   
51          depth = len(name) 
52          if depth > self.max_depth: 
53              depth = self.max_depth 
54          for i in xrange(-depth, 0): 
55              n = dns.name.Name(name[i:]) 
56              if self.has_key(n): 
57                  return (n, self[n]) 
58          v = self[dns.name.empty] 
59          return (dns.name.empty, v) 
60