apps/catalogue/helpers.py

   1 from datetime import date
   2 from functools import wraps
   3
   4 from django.db.models import Count
   5
   6
   7 def active_tab(tab):
   8     """
   9         View decorator, which puts tab info on a request.
  10     """
  11     def wrapper(f):
  12         @wraps(f)
  13         def wrapped(request, *args, **kwargs):
  14             request.catalogue_active_tab = tab
  15             return f(request, *args, **kwargs)
  16         return wrapped
  17     return wrapper
  18
  19
  20 def cached_in_field(field_name):
  21     def decorator(f):
  22         @property
  23         @wraps(f)
  24         def wrapped(self, *args, **kwargs):
  25             value = getattr(self, field_name)
  26             if value is None:
  27                 value = f(self, *args, **kwargs)
  28                 type(self)._default_manager.filter(pk=self.pk).update(**{field_name: value})
  29             return value
  30         return wrapped
  31     return decorator
  32
  33
  34 def parse_isodate(isodate):
  35     try:
  36         return date(*[int(p) for p in isodate.split('-')])
  37     except (AttributeError, TypeError, ValueError):
  38         raise ValueError("Not a date in ISO format.")