django1/django/views/generic/list.py

146 lines
5.5 KiB
Python

from django.core.paginator import Paginator, InvalidPage
from django.core.exceptions import ImproperlyConfigured
from django.http import Http404
from django.utils.encoding import smart_str
from django.views.generic.base import TemplateResponseMixin, View
class MultipleObjectMixin(object):
allow_empty = True
queryset = None
model = None
paginate_by = None
context_object_name = None
paginator_class = Paginator
def get_queryset(self):
"""
Get the list of items for this view. This must be an interable, and may
be a queryset (in which qs-specific behavior will be enabled).
"""
if self.queryset is not None:
queryset = self.queryset
if hasattr(queryset, '_clone'):
queryset = queryset._clone()
elif self.model is not None:
queryset = self.model._default_manager.all()
else:
raise ImproperlyConfigured(u"'%s' must define 'queryset' or 'model'"
% self.__class__.__name__)
return queryset
def paginate_queryset(self, queryset, page_size):
"""
Paginate the queryset, if needed.
"""
paginator = self.get_paginator(queryset, page_size, allow_empty_first_page=self.get_allow_empty())
if paginator.num_pages > 1:
page = self.kwargs.get('page') or self.request.GET.get('page') 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, True)
except InvalidPage:
raise Http404(u'Invalid page (%s)' % page_number)
else:
return (None, None, queryset, False)
def get_paginate_by(self, queryset):
"""
Get the number of items to paginate by, or ``None`` for no pagination.
"""
return self.paginate_by
def get_paginator(self, queryset, per_page, orphans=0, allow_empty_first_page=True):
"""
Return an instance of the paginator for this view.
"""
return self.paginator_class(queryset, per_page, orphans=orphans, allow_empty_first_page=allow_empty_first_page)
def get_allow_empty(self):
"""
Returns ``True`` if the view should display empty lists, and ``False``
if a 404 should be raised instead.
"""
return self.allow_empty
def get_context_object_name(self, object_list):
"""
Get the name of the item to be used in the context.
"""
if self.context_object_name:
return self.context_object_name
elif hasattr(object_list, 'model'):
return smart_str(object_list.model._meta.verbose_name_plural)
else:
return None
def get_context_data(self, **kwargs):
"""
Get the context for this view.
"""
queryset = kwargs.pop('object_list')
page_size = self.get_paginate_by(queryset)
if page_size:
paginator, page, queryset, is_paginated = self.paginate_queryset(queryset, page_size)
context = {
'paginator': paginator,
'page_obj': page,
'is_paginated': is_paginated,
'object_list': queryset
}
else:
context = {
'paginator': None,
'page_obj': None,
'is_paginated': False,
'object_list': queryset
}
context.update(kwargs)
context_object_name = self.get_context_object_name(queryset)
if context_object_name is not None:
context[context_object_name] = queryset
return context
class BaseListView(MultipleObjectMixin, View):
def get(self, request, *args, **kwargs):
self.object_list = self.get_queryset()
allow_empty = self.get_allow_empty()
if not allow_empty and len(self.object_list) == 0:
raise Http404(u"Empty list and '%s.allow_empty' is False."
% self.__class__.__name__)
context = self.get_context_data(object_list=self.object_list)
return self.render_to_response(context)
class MultipleObjectTemplateResponseMixin(TemplateResponseMixin):
template_name_suffix = '_list'
def get_template_names(self):
"""
Return a list of template names to be used for the request. Must return
a list. May not be called if get_template is overridden.
"""
names = super(MultipleObjectTemplateResponseMixin, self).get_template_names()
# If the list is a queryset, we'll invent a template name based on the
# app and model name. This name gets put at the end of the template
# name list so that user-supplied names override the automatically-
# generated ones.
if hasattr(self.object_list, 'model'):
opts = self.object_list.model._meta
names.append("%s/%s%s.html" % (opts.app_label, opts.object_name.lower(), self.template_name_suffix))
return names
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.
"""