common/python/rift/mano/utils/short_name.py

   1 #!/usr/bin/python
   2
   3 #
   4 #   Copyright 2017 RIFT.IO Inc
   5 #
   6 #   Licensed under the Apache License, Version 2.0 (the "License");
   7 #   you may not use this file except in compliance with the License.
   8 #   You may obtain a copy of the License at
   9 #
  10 #       http://www.apache.org/licenses/LICENSE-2.0
  11 #
  12 #   Unless required by applicable law or agreed to in writing, software
  13 #   distributed under the License is distributed on an "AS IS" BASIS,
  14 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15 #   See the License for the specific language governing permissions and
  16 #   limitations under the License.
  17 #
  18 # Author: Aniruddha Atale
  19
  20 import hashlib
  21 import basehash
  22
  23
  24 class StringShortner(object):
  25     FOLDS = 3
  26     STRING_LEN=9
  27     def __init__(self, string = None):
  28         self._string = string
  29
  30     @property
  31     def string(self):
  32         return self._string
  33
  34     @string.setter
  35     def string(self, string):
  36         self._string = string
  37
  38     @property
  39     def short_string(self):
  40         if self._string:
  41             return StringShortner._get_short_string(self._string)
  42         else:
  43             return str()
  44
  45     @staticmethod
  46     def _fold_hex_series(series):
  47         length = len(series)
  48         result = list()
  49         for i in range(int(length/2)):
  50             result.append(series[i] ^ series[(length - 1) - i])
  51
  52         if length % 2:
  53             result.append(series[int(length/2) + 1])
  54
  55         return result
  56
  57     @staticmethod
  58     def _num_from_hex_series(series):
  59         result = 0
  60         for i in range(len(series)):
  61             result = result * 256
  62             result += series[i]
  63         return result
  64
  65     @staticmethod
  66     def _get_short_string(string):
  67         sha = hashlib.sha384(string.encode())
  68         digest = sha.digest()
  69         for i in range(StringShortner.FOLDS):
  70             digest = StringShortner._fold_hex_series(digest)
  71
  72         number = StringShortner._num_from_hex_series(digest)
  73         base62 = basehash.base62(length=StringShortner.STRING_LEN)
  74         return base62.hash(number)