3
class InvalidPage(Exception):
6
class PageNotAnInteger(InvalidPage):
9
class EmptyPage(InvalidPage):
12
class Paginator(object):
13
def __init__(self, object_list, per_page, orphans=0, allow_empty_first_page=True):
14
self.object_list = object_list
15
self.per_page = per_page
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self.orphans = orphans
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self.allow_empty_first_page = allow_empty_first_page
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self._num_pages = self._count = None
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def validate_number(self, number):
21
"Validates the given 1-based page number."
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raise PageNotAnInteger('That page number is not an integer')
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raise EmptyPage('That page number is less than 1')
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if number > self.num_pages:
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if number == 1 and self.allow_empty_first_page:
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raise EmptyPage('That page contains no results')
35
def page(self, number):
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"Returns a Page object for the given 1-based page number."
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number = self.validate_number(number)
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bottom = (number - 1) * self.per_page
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top = bottom + self.per_page
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if top + self.orphans >= self.count:
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return Page(self.object_list[bottom:top], number, self)
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"Returns the total number of objects, across all pages."
46
if self._count is None:
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self._count = self.object_list.count()
49
except (AttributeError, TypeError):
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# AttributeError if object_list has no count() method.
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# TypeError if object_list.count() requires arguments
52
# (i.e. is of type list).
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self._count = len(self.object_list)
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count = property(_get_count)
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def _get_num_pages(self):
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"Returns the total number of pages."
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if self._num_pages is None:
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if self.count == 0 and not self.allow_empty_first_page:
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hits = max(1, self.count - self.orphans)
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self._num_pages = int(ceil(hits / float(self.per_page)))
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return self._num_pages
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num_pages = property(_get_num_pages)
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def _get_page_range(self):
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Returns a 1-based range of pages for iterating through within
73
return range(1, self.num_pages + 1)
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page_range = property(_get_page_range)
76
QuerySetPaginator = Paginator # For backwards-compatibility.
79
def __init__(self, object_list, number, paginator):
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self.object_list = object_list
82
self.paginator = paginator
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return '<Page %s of %s>' % (self.number, self.paginator.num_pages)
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return self.number < self.paginator.num_pages
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def has_previous(self):
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return self.number > 1
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def has_other_pages(self):
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return self.has_previous() or self.has_next()
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def next_page_number(self):
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return self.number + 1
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def previous_page_number(self):
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return self.number - 1
102
def start_index(self):
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Returns the 1-based index of the first object on this page,
105
relative to total objects in the paginator.
107
# Special case, return zero if no items.
108
if self.paginator.count == 0:
110
return (self.paginator.per_page * (self.number - 1)) + 1
114
Returns the 1-based index of the last object on this page,
115
relative to total objects found (hits).
117
# Special case for the last page because there can be orphans.
118
if self.number == self.paginator.num_pages:
119
return self.paginator.count
120
return self.number * self.paginator.per_page