I'm currently working on CBV Paginator in Django redirecting last page when given page exceed maximum pages. So, let's say there's Post models that has 200 instances and ListView with paginated_by=10. Then maximum page is 20.
So, when I enter URL with "?page=21", it return 404 Error Page. I want to redirect to maximum page.
How can I do?
If you take a look at django.views.generic.listlink you have the following ListView class:
class ListView(MultipleObjectTemplateResponseMixin, BaseListView):
"""
Render some list of objects, set by `self.model` or `self.queryset`.
`self.queryset` can actually be any iterable of items, not just a queryset.
"""
which include BaseListView for pagination which inherit from MultipleObjectMixin:
class MultipleObjectMixin(ContextMixin):
"""A mixin for views manipulating multiple objects."""
... #other functions
def paginate_queryset(self, queryset, page_size):
"""Paginate the queryset, if needed."""
paginator = self.get_paginator(
queryset, page_size, orphans=self.get_paginate_orphans(),
allow_empty_first_page=self.get_allow_empty())
page_kwarg = self.page_kwarg
page = self.kwargs.get(page_kwarg) or self.request.GET.get(page_kwarg) or 1
try:
page_number = int(page)
except ValueError:
if page == 'last':
page_number = paginator.num_pages
else:
raise Http404(_("Page is not 'last', nor can it be converted to an int."))
try:
page = paginator.page(page_number)
return (paginator, page, page.object_list, page.has_other_pages())
except InvalidPage as e:
raise Http404(_('Invalid page (%(page_number)s): %(message)s') % {
'page_number': page_number,
'message': str(e)
}) #<- the 404 page you want to redirect
You need to override the InvalidPage exception handling which raise the Http404:
from django.views.generic.list import ListView
class YourListView(ListView):
def paginate_queryset(self, queryset, page_size):
"""Paginate the queryset, if needed."""
paginator = self.get_paginator(
queryset, page_size, orphans=self.get_paginate_orphans(),
allow_empty_first_page=self.get_allow_empty())
page_kwarg = self.page_kwarg
page = self.kwargs.get(page_kwarg) or self.request.GET.get(page_kwarg) or 1
try:
page_number = int(page)
except ValueError:
if page == 'last':
page_number = paginator.num_pages
else:
raise Http404(_("Page is not 'last', nor can it be converted to an int."))
try:
page = paginator.page(page_number)
return (paginator, page, page.object_list, page.has_other_pages())
except InvalidPage as e:
page_number = paginator.num_pages #<-last page
page = paginator.page(page_number)
return (paginator, page, page.object_list, page.has_other_pages()) #<-return last page
Note: you can also use this custom class for other ListView