| # Copyright (C) 2003-2007, 2009, 2010 Nominum, Inc. |
| # |
| # Permission to use, copy, modify, and distribute this software and its |
| # documentation for any purpose with or without fee is hereby granted, |
| # provided that the above copyright notice and this permission notice |
| # appear in all copies. |
| # |
| # THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES |
| # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR |
| # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT |
| # OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| |
| """DNS name dictionary""" |
| |
| import dns.name |
| |
| class NameDict(dict): |
| |
| """A dictionary whose keys are dns.name.Name objects. |
| @ivar max_depth: the maximum depth of the keys that have ever been |
| added to the dictionary. |
| @type max_depth: int |
| """ |
| |
| def __init__(self, *args, **kwargs): |
| super(NameDict, self).__init__(*args, **kwargs) |
| self.max_depth = 0 |
| |
| def __setitem__(self, key, value): |
| if not isinstance(key, dns.name.Name): |
| raise ValueError('NameDict key must be a name') |
| depth = len(key) |
| if depth > self.max_depth: |
| self.max_depth = depth |
| super(NameDict, self).__setitem__(key, value) |
| |
| def get_deepest_match(self, name): |
| """Find the deepest match to I{name} in the dictionary. |
| |
| The deepest match is the longest name in the dictionary which is |
| a superdomain of I{name}. |
| |
| @param name: the name |
| @type name: dns.name.Name object |
| @rtype: (key, value) tuple |
| """ |
| |
| depth = len(name) |
| if depth > self.max_depth: |
| depth = self.max_depth |
| for i in xrange(-depth, 0): |
| n = dns.name.Name(name[i:]) |
| if self.has_key(n): |
| return (n, self[n]) |
| v = self[dns.name.empty] |
| return (dns.name.empty, v) |
