Commit 03f86a5a authored by Aymeric Augustin's avatar Aymeric Augustin
Browse files

Fixed #18354 -- Performance issue in CBV. 

Prevented repeating a query twice when the model isn't ordered by
-date_field (in Meta), allow_empty is False and pagination isn't
enabled.
parent b0c1e5c0

django/views/generic/dates.py

+12 −13
Original line number Diff line number Diff line
@@ -315,7 +315,7 @@ class BaseDateListView(MultipleObjectMixin, DateMixin, View): 
        """

        raise NotImplementedError('A DateView must provide an implementation of get_dated_items()')



    def get_dated_queryset(self, **lookup):

    def get_dated_queryset(self, ordering=None, **lookup):

        """

        Get a queryset properly filtered according to `allow_future` and any

        extra lookup kwargs.
@@ -326,6 +326,9 @@ class BaseDateListView(MultipleObjectMixin, DateMixin, View): 
        allow_empty = self.get_allow_empty()

        paginate_by = self.get_paginate_by(qs)



        if ordering is not None:

            qs = qs.order_by(ordering)



        if not allow_future:

            now = timezone.now() if self.uses_datetime_field else timezone_today()

            qs = qs.filter(**{'%s__lte' % date_field: now})
@@ -370,15 +373,13 @@ class BaseArchiveIndexView(BaseDateListView): 
        """

        Return (date_list, items, extra_context) for this request.

        """

        qs = self.get_dated_queryset()

        qs = self.get_dated_queryset(ordering='-%s' % self.get_date_field())

        date_list = self.get_date_list(qs, 'year')



        if date_list:

            object_list = qs.order_by('-' + self.get_date_field())

        else:

            object_list = qs.none()

        if not date_list:

            qs = qs.none()



        return (date_list, object_list, {})

        return (date_list, qs, {})





class ArchiveIndexView(MultipleObjectTemplateResponseMixin, BaseArchiveIndexView):
@@ -410,17 +411,15 @@ class BaseYearArchiveView(YearMixin, BaseDateListView): 
            '%s__lt' % date_field: until,

        }



        qs = self.get_dated_queryset(**lookup_kwargs)

        qs = self.get_dated_queryset(ordering='-%s' % date_field, **lookup_kwargs)

        date_list = self.get_date_list(qs, 'month')



        if self.get_make_object_list():

            object_list = qs.order_by('-' + date_field)

        else:

        if not self.get_make_object_list():

            # We need this to be a queryset since parent classes introspect it

            # to find information about the model.

            object_list = qs.none()

            qs = qs.none()



        return (date_list, object_list, {'year': year})

        return (date_list, qs, {'year': year})



    def get_make_object_list(self):

        """

tests/regressiontests/generic_views/dates.py

+12 −2
Original line number Diff line number Diff line
@@ -86,10 +86,15 @@ class ArchiveIndexViewTests(TestCase): 
        # 1 query for years list + 1 query for books

        with self.assertNumQueries(2):

            self.client.get('/dates/books/')

        # same as above + 1 query to test if books exist

        with self.assertNumQueries(3):

        # same as above + 1 query to test if books exist + 1 query to count them

        with self.assertNumQueries(4):

            self.client.get('/dates/books/paginated/')



    def test_no_duplicate_query(self):

        # Regression test for #18354

        with self.assertNumQueries(2):

            self.client.get('/dates/books/reverse/')



    def test_datetime_archive_view(self):

        BookSigning.objects.create(event_date=datetime.datetime(2008, 4, 2, 12, 0))

        res = self.client.get('/dates/booksignings/')
@@ -155,6 +160,11 @@ class YearArchiveViewTests(TestCase): 
        res = self.client.get('/dates/books/no_year/')

        self.assertEqual(res.status_code, 404)



    def test_no_duplicate_query(self):

        # Regression test for #18354

        with self.assertNumQueries(2):

            self.client.get('/dates/books/2008/reverse/')



    def test_datetime_year_view(self):

        BookSigning.objects.create(event_date=datetime.datetime(2008, 4, 2, 12, 0))

        res = self.client.get('/dates/booksignings/2008/')

tests/regressiontests/generic_views/templates/generic_views/book_archive.html

+1 −1
Original line number Diff line number Diff line 
Archive of books from {{ date_list }}.
 
 No newline at end of file
 
Archive of books from {{ date_list }}. {{ object_list|length }} books found.

tests/regressiontests/generic_views/templates/generic_views/book_archive_year.html

+1 −1
Original line number Diff line number Diff line 
Archive of books from {{ year }}.
 
 No newline at end of file
 
Archive of books from {{ year }}. {{ object_list|length }} books found.

tests/regressiontests/generic_views/urls.py

+5 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ from django.conf.urls import patterns, url 
from django.views.decorators.cache import cache_page

from django.views.generic import TemplateView



from . import models

from . import views
@@ -108,6 +109,8 @@ urlpatterns = patterns('', 
        views.BookArchive.as_view(queryset=None)),

    (r'^dates/books/paginated/$',

        views.BookArchive.as_view(paginate_by=10)),

    (r'^dates/books/reverse/$',

        views.BookArchive.as_view(queryset=models.Book.objects.order_by('pubdate'))),

    (r'^dates/booksignings/$',

        views.BookSigningArchive.as_view()),
@@ -160,6 +163,8 @@ urlpatterns = patterns('', 
        views.BookYearArchive.as_view(make_object_list=True, paginate_by=30)),

    (r'^dates/books/no_year/$',

        views.BookYearArchive.as_view()),

    (r'^dates/books/(?P<year>\d{4})/reverse/$',

        views.BookYearArchive.as_view(queryset=models.Book.objects.order_by('pubdate'))),

    (r'^dates/booksignings/(?P<year>\d{4})/$',

        views.BookSigningYearArchive.as_view()),