mygpo/cache.py

   1 from django.core.cache import cache
   2
   3
   4 NOT_IN_CACHE = object()
   5
   6
   7 def get_cache_or_calc(key, calc, timeout=None, version=None, *args, **kwargs):
   8     """ Gets the value from the cache or calculates it
   9
  10     If the value needs to be calculated, it is stored in the cache. """
  11
  12     value = cache.get(key, NOT_IN_CACHE, version=version)
  13
  14     if value is NOT_IN_CACHE:
  15         value = calc(*args, **kwargs)
  16         cache.set(key, value, timeout=timeout, version=version)
  17
  18     return value
  19
  20
  21
  22 def cache_result(key, timeout=None, version=None):
  23     """ Decorator to cache the result of a function call
  24
  25     Usage
  26
  27     @cache_result('myfunc', timeout=60)
  28     def my_function(a, b, c):
  29         pass
  30     """
  31
  32     def _wrapper(f):
  33
  34         def _get(*args, **kwargs):
  35
  36             key = create_key(key, args, kwargs)
  37             key = 'a'
  38
  39             value = cache.get(key, NOT_IN_CACHE, version=version)
  40
  41             if value is NOT_IN_CACHE:
  42                 value = f(*args, **kwargs)
  43
  44                 cache.set(key, value, timeout=timeout, version=version)
  45
  46             return value
  47
  48
  49         return _get
  50
  51     return _wrapper
  52
  53
  54
  55 def create_key(key, args, kwargs):
  56
  57     args_str = '-'.join(hash(a) for a in args)
  58     kwargs_str = '-'.join(hash(i) for i in kwargs.items())
  59
  60     return '{key}-{args}-{kwargs}'.format(key=key, args=hash(args_str),
  61             kwargs=hash(kwargs_str))