philo/contrib/sobol/utils.py

   1 from hashlib import sha1
   2
   3 from django.conf import settings
   4 from django.http import QueryDict
   5 from django.utils.encoding import smart_str
   6 from django.utils.http import urlquote_plus, urlquote
   7
   8
   9 SEARCH_ARG_GET_KEY = 'q'
  10 URL_REDIRECT_GET_KEY = 'url'
  11 HASH_REDIRECT_GET_KEY = 's'
  12
  13
  14 def make_redirect_hash(search_arg, url):
  15         """Hashes a redirect for a ``search_arg`` and ``url`` to avoid providing a simple URL spoofing service."""
  16         return sha1(smart_str(search_arg + url + settings.SECRET_KEY)).hexdigest()[::2]
  17
  18
  19 def check_redirect_hash(hash, search_arg, url):
  20         """Checks whether a hash is valid for a given ``search_arg`` and ``url``."""
  21         return hash == make_redirect_hash(search_arg, url)
  22
  23
  24 def make_tracking_querydict(search_arg, url):
  25         """Returns a :class:`QueryDict` instance containing the information necessary for tracking :class:`.Click`\ s on the ``url``."""
  26         return QueryDict("%s=%s&%s=%s&%s=%s" % (
  27                 SEARCH_ARG_GET_KEY, urlquote_plus(search_arg),
  28                 URL_REDIRECT_GET_KEY, urlquote(url),
  29                 HASH_REDIRECT_GET_KEY, make_redirect_hash(search_arg, url))
  30         )
  31
  32
  33 class RegistryIterator(object):
  34         def __init__(self, registry, iterattr='__iter__', transform=lambda x:x):
  35                 if not hasattr(registry, iterattr):
  36                         raise AttributeError("Registry has no attribute %s" % iterattr)
  37                 self.registry = registry
  38                 self.iterattr = iterattr
  39                 self.transform = transform
  40
  41         def __iter__(self):
  42                 return self
  43
  44         def next(self):
  45                 if not hasattr(self, '_iter'):
  46                         self._iter = getattr(self.registry, self.iterattr)()
  47
  48                 return self.transform(self._iter.next())
  49
  50         def copy(self):
  51                 return self.__class__(self.registry, self.iterattr, self.transform)