#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright (c) 2009-2011, Nicolas Clairon
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import sys
DEFAULT_LIMIT = 10
[docs]class Paginator(object):
""" Provides pagination on a Cursor object
Keyword arguments:
cursor -- Cursor of a returned query
page -- The page number requested
limit -- The number of items per page
Properties:
items -- Returns the paginated Cursor object
is_paginated -- Boolean value determining if the cursor has multiple pages
start_index -- int index of the first item on the requested page
end_index -- int index of the last item on the requested page
current_page -- int page number of the requested page
previous_page-- int page number of the previous page w.r.t. current requested page
next_page -- int page number of the next page w.r.t. current requested page
has_next -- True or False if the Cursor has a next page
has_previous -- True or False if the Cursor has a previous page
page_range -- list of page numbers
num_pages -- int of the number of pages
count -- int total number of items on the cursor
"""
def __init__(self, cursor, page=1, limit=DEFAULT_LIMIT):
self._cursor = cursor
self._count = self._cursor.count() if cursor else 0
self._limit = limit
self._page = int(page)
self._set_page(self._page)
@property
def items(self):
return self._cursor
@property
def is_paginated(self):
return self.num_pages > 1
@property
def start_index(self):
if self._page == 1:
return 1
if self._limit == 1:
return self._page
return ((self._page - 1) * self._limit) + 1
@property
def end_index(self):
if self._limit == 1:
return self._page
if self._page == 1:
return self._count if self._count < self._limit else self._limit
calc_end = (self._page * self._limit)
return calc_end if calc_end < self._count else self._count
@property
def current_page(self):
return self._page
@property
def previous_page(self):
return self._page - 1
@property
def next_page(self):
return self._page + 1
@property
def has_next(self):
return self.end_index < self._count
@property
def has_previous(self):
return self.start_index - self._limit >= 0
@property
def page_range(self):
if sys.version_info < (3,):
return [p for p in xrange(1, self.num_pages + 1)]
else:
return [p for p in range(1, self.num_pages + 1)]
@property
def num_pages(self):
if self._count <= 0:
return 0
if self._count <= self._limit:
return 1
pages_f = self._count / float(self._limit)
pages_i = int(pages_f)
return (pages_i + 1) if pages_f > pages_i else pages_i
@property
def count(self):
return self._count
def _set_page(self, _):
if self._page > 1:
self._cursor.skip(self.start_index - 1)
if self._cursor:
self._cursor.limit(self._limit)