Package dns :: Module namedict |
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# 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