~netlandish/django-pagination

03487c9ca03131fa299070774aaf639f8e613cb6 — leahculver 15 years ago 43c7ea5
silly FinitePaginator for finite lists of items

Signed-off-by: Eric Florenzano <floguy@gmail.com>
2 files changed, 99 insertions(+), 1 deletions(-)

M pagination/paginator.py
M pagination/tests.py
M pagination/paginator.py => pagination/paginator.py +57 -1
@@ 92,4 92,60 @@ class InfinitePage(Page):
    def previous_link(self):
        if self.has_previous():
            return self.paginator.link_template % (self.number - 1)
        return None
\ No newline at end of file
        return None

class FinitePaginator(InfinitePaginator):
    '''
        Paginator for cases when the list of items is already finite.

        A good example is a list generated from an API call. This is a subclass
        of InfinitePaginator because we have no idea how many items exist in the
        full collection.

        To accurately determine if the next page exists, a FinitePaginator MUST be created
        with an object_list_plus that may contain more items than the per_page count.
        Typically, you'll have an object_list_plus with one extra item (if there's a next page).
        You'll also need to supply the offset from the full collection in order to get the
        page start_index.

        This is a very silly class but useful if you love the Django pagination conventions.
    '''

    def __init__(self, object_list_plus, per_page, offset=None, allow_empty_first_page=True, link_template='/page/%d/'):
        super(FinitePaginator, self).__init__(object_list_plus, per_page, allow_empty_first_page, link_template)
        self.offset = offset

    def validate_number(self, number):
        super(FinitePaginator, self).validate_number(number)
        # check for an empty list to see if the page exists
        if not self.object_list:
            if number == 1 and self.allow_empty_first_page:
                pass
            else:
                raise EmptyPage('That page contains no results')
        return number

    def page(self, number):
        "Returns a Page object for the given 1-based page number."
        number = self.validate_number(number)
        # remove the extra item(s) when creating the page
        page_items = self.object_list[:self.per_page]
        return FinitePage(page_items, number, self)

class FinitePage(InfinitePage):

    def has_next(self):
        "Checks for one more item than last on this page."
        try:
            next_item = self.paginator.object_list[self.paginator.per_page]
        except IndexError:
            return False
        return True

    def start_index(self):
        """
        Returns the 1-based index of the first object on this page,
        relative to total objects in the paginator.
        """
        ## TODO should this holler if you haven't defined the offset?
        return self.paginator.offset
\ No newline at end of file

M pagination/tests.py => pagination/tests.py +42 -0
@@ 62,6 62,7 @@ u'[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19]'
# Testing InfinitePaginator

>>> from paginator import InfinitePaginator

>>> InfinitePaginator
<class 'pagination.paginator.InfinitePaginator'>
>>> p = InfinitePaginator(range(20), 2, link_template='/bacon/page/%d')


@@ 86,4 87,45 @@ False
'/bacon/page/4'
>>> p3.previous_link()
'/bacon/page/2'

# Testing FinitePaginator

>>> from paginator import FinitePaginator

>>> FinitePaginator
<class 'pagination.paginator.FinitePaginator'>
>>> p = FinitePaginator(range(20), 2, offset=10, link_template='/bacon/page/%d')
>>> p.validate_number(2)
2
>>> p.orphans
0
>>> p3 = p.page(3)
>>> p3
<Page 3>
>>> p3.start_index()
10
>>> p3.end_index()
6
>>> p3.has_next()
True
>>> p3.has_previous()
True
>>> p3.next_link()
'/bacon/page/4'
>>> p3.previous_link()
'/bacon/page/2'

>>> p = FinitePaginator(range(20), 20, offset=10, link_template='/bacon/page/%d')
>>> p2 = p.page(2)
>>> p2
<Page 2>
>>> p2.has_next()
False
>>> p3.has_previous()
True
>>> p2.next_link()

>>> p2.previous_link()
'/bacon/page/1'

"""
\ No newline at end of file