contrib/penfield/utils.py

   1 from django.core.paginator import Paginator, EmptyPage
   2
   3
   4 class PaginationProxy(object):
   5         def __init__(self, paginator=None, page=None, objects=None):
   6                 self.paginator = paginator
   7                 self.page = page
   8                 self.objects = objects
   9
  10         @property
  11         def page_range(self):
  12                 if not self.paginator:
  13                         return None
  14
  15                 return self.paginator.page_range
  16
  17         @property
  18         def num_pages(self):
  19                 if not self.paginator:
  20                         return None
  21
  22                 return self.paginator.num_pages
  23
  24         @property
  25         def page_number(self):
  26                 if not self.page:
  27                         return None
  28
  29                 return self.page.number
  30
  31         # Why doesn't this work?
  32         #def __bool__(self):
  33         #       return bool(self.paginator)
  34
  35
  36 def paginate(objects, per_page=None, page_number=1):
  37         """
  38         Given a list of objects, return a (page, obj_list) tuple.
  39         """
  40         try:
  41                 per_page = int(per_page)
  42         except (TypeError, ValueError):
  43                 # Then either it wasn't set or it was set to an invalid value
  44                 return PaginationProxy(objects=objects)
  45
  46         # There also shouldn't be pagination if the list is too short. Try count()
  47         # first - good chance it's a queryset, where count is more efficient.
  48         try:
  49                 if objects.count() <= per_page:
  50                         return PaginationProxy(objects=objects)
  51         except AttributeError:
  52                 if len(objects) <= per_page:
  53                         return PaginationProxy(objects=objects)
  54
  55         paginator = Paginator(objects, per_page)
  56         try:
  57                 page_number = int(page_number)
  58         except:
  59                 page_number = 1
  60
  61         try:
  62                 page = paginator.page(page_number)
  63         except EmptyPage:
  64                 page = None
  65
  66         return PaginationProxy(paginator, page, objects)