Класс BaseDateListView (Django 2.0)
from django.views.generic.dates import BaseDateListView
Abstract base class for date-based views displaying a list of objects.
Предки (MRO)
- BaseDateListView
- MultipleObjectMixin
- ContextMixin
- DateMixin
- View
Атрибуты
Определено в | |
---|---|
allow_empty = False
|
BaseDateListView |
allow_empty = True
|
MultipleObjectMixin |
allow_future = False
|
DateMixin |
context_object_name = None
|
MultipleObjectMixin |
date_field = None
|
DateMixin |
date_list_period = 'year'
|
BaseDateListView |
extra_context = None
|
ContextMixin |
http_method_names = ['get', 'post', 'put', 'patch', 'delete', 'head', 'options', 'trace']
|
View |
model = None
|
MultipleObjectMixin |
ordering = None
|
MultipleObjectMixin |
page_kwarg = 'page'
|
MultipleObjectMixin |
paginate_by = None
|
MultipleObjectMixin |
paginate_orphans = 0
|
MultipleObjectMixin |
paginator_class = <class 'django.core.paginator.Paginator'>
|
MultipleObjectMixin |
queryset = None
|
MultipleObjectMixin |
uses_datetime_field = <django.utils.functional.cached_property object at 0x7f2e9bb9b240>
|
DateMixin |
Методы
def _allowed_methods(self):
return [m.upper() for m in self.http_method_names if hasattr(self, m)]
Основная точка входа процесса "запрос-ответ".
@classonlymethod
def as_view(cls, **initkwargs):
"""Main entry point for a request-response process."""
for key in initkwargs:
if key in cls.http_method_names:
raise TypeError("You tried to pass in the %s method name as a "
"keyword argument to %s(). Don't do that."
% (key, cls.__name__))
if not hasattr(cls, key):
raise TypeError("%s() received an invalid keyword %r. as_view "
"only accepts arguments that are already "
"attributes of the class." % (cls.__name__, key))
def view(request, *args, **kwargs):
self = cls(**initkwargs)
if hasattr(self, 'get') and not hasattr(self, 'head'):
self.head = self.get
self.request = request
self.args = args
self.kwargs = kwargs
return self.dispatch(request, *args, **kwargs)
view.view_class = cls
view.view_initkwargs = initkwargs
# take name and docstring from class
update_wrapper(view, cls, updated=())
# and possible attributes set by decorators
# like csrf_exempt from dispatch
update_wrapper(view, cls.dispatch, assigned=())
return view
def dispatch(self, request, *args, **kwargs):
# Try to dispatch to the right method; if a method doesn't exist,
# defer to the error handler. Also defer to the error handler if the
# request method isn't on the approved list.
if request.method.lower() in self.http_method_names:
handler = getattr(self, request.method.lower(), self.http_method_not_allowed)
else:
handler = self.http_method_not_allowed
return handler(request, *args, **kwargs)
def get(self, request, *args, **kwargs):
self.date_list, self.object_list, extra_context = self.get_dated_items()
context = self.get_context_data(
object_list=self.object_list,
date_list=self.date_list,
**extra_context
)
return self.render_to_response(context)
Return ``True`` if the view should display empty lists and ``False`` if a 404 should be raised instead.
def get_allow_empty(self):
"""
Return ``True`` if the view should display empty lists and ``False``
if a 404 should be raised instead.
"""
return self.allow_empty
Return `True` if the view should be allowed to display objects from the future.
def get_allow_future(self):
"""
Return `True` if the view should be allowed to display objects from
the future.
"""
return self.allow_future
MultipleObjectMixin
Get the context for this view.
def get_context_data(self, *, object_list=None, **kwargs):
"""Get the context for this view."""
queryset = object_list if object_list is not None else self.object_list
page_size = self.get_paginate_by(queryset)
context_object_name = self.get_context_object_name(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
}
if context_object_name is not None:
context[context_object_name] = queryset
context.update(kwargs)
return super().get_context_data(**context)
ContextMixin
def get_context_data(self, **kwargs):
if 'view' not in kwargs:
kwargs['view'] = self
if self.extra_context is not None:
kwargs.update(self.extra_context)
return kwargs
Get the name of the item to be used in the context.
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 '%s_list' % object_list.model._meta.model_name
else:
return None
Obtain the list of dates and items.
def get_dated_items(self):
"""Obtain the list of dates and items."""
raise NotImplementedError('A DateView must provide an implementation of get_dated_items()')
Get a queryset properly filtered according to `allow_future` and any extra lookup kwargs.
def get_dated_queryset(self, **lookup):
"""
Get a queryset properly filtered according to `allow_future` and any
extra lookup kwargs.
"""
qs = self.get_queryset().filter(**lookup)
date_field = self.get_date_field()
allow_future = self.get_allow_future()
allow_empty = self.get_allow_empty()
paginate_by = self.get_paginate_by(qs)
if not allow_future:
now = timezone.now() if self.uses_datetime_field else timezone_today()
qs = qs.filter(**{'%s__lte' % date_field: now})
if not allow_empty:
# When pagination is enabled, it's better to do a cheap query
# than to load the unpaginated queryset in memory.
is_empty = len(qs) == 0 if paginate_by is None else not qs.exists()
if is_empty:
raise Http404(_("No %(verbose_name_plural)s available") % {
'verbose_name_plural': qs.model._meta.verbose_name_plural,
})
return qs
Get the name of the date field to be used to filter by.
def get_date_field(self):
"""Get the name of the date field to be used to filter by."""
if self.date_field is None:
raise ImproperlyConfigured("%s.date_field is required." % self.__class__.__name__)
return self.date_field
Get a date list by calling `queryset.dates/datetimes()`, checking along the way for empty lists that aren't allowed.
def get_date_list(self, queryset, date_type=None, ordering='ASC'):
"""
Get a date list by calling `queryset.dates/datetimes()`, checking
along the way for empty lists that aren't allowed.
"""
date_field = self.get_date_field()
allow_empty = self.get_allow_empty()
if date_type is None:
date_type = self.get_date_list_period()
if self.uses_datetime_field:
date_list = queryset.datetimes(date_field, date_type, ordering)
else:
date_list = queryset.dates(date_field, date_type, ordering)
if date_list is not None and not date_list and not allow_empty:
raise Http404(
_("No %(verbose_name_plural)s available") % {
'verbose_name_plural': queryset.model._meta.verbose_name_plural,
}
)
return date_list
Get the aggregation period for the list of dates: 'year', 'month', or 'day'.
def get_date_list_period(self):
"""
Get the aggregation period for the list of dates: 'year', 'month', or
'day'.
"""
return self.date_list_period
BaseDateListView
Return the field or fields to use for ordering the queryset; use the date field by default.
def get_ordering(self):
"""
Return the field or fields to use for ordering the queryset; use the
date field by default.
"""
return '-%s' % self.get_date_field() if self.ordering is None else self.ordering
MultipleObjectMixin
Return the field or fields to use for ordering the queryset.
def get_ordering(self):
"""Return the field or fields to use for ordering the queryset."""
return self.ordering
Get the number of items to paginate by, or ``None`` for no pagination.
def get_paginate_by(self, queryset):
"""
Get the number of items to paginate by, or ``None`` for no pagination.
"""
return self.paginate_by
Return the maximum number of orphans extend the last page by when paginating.
def get_paginate_orphans(self):
"""
Return the maximum number of orphans extend the last page by when
paginating.
"""
return self.paginate_orphans
Return an instance of the paginator for this view.
def get_paginator(self, queryset, per_page, orphans=0,
allow_empty_first_page=True, **kwargs):
"""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, **kwargs)
Return the list of items for this view. The return value must be an iterable and may be an instance of `QuerySet` in which case `QuerySet` specific behavior will be enabled.
def get_queryset(self):
"""
Return the list of items for this view.
The return value must be an iterable and may be an instance of
`QuerySet` in which case `QuerySet` specific behavior will be enabled.
"""
if self.queryset is not None:
queryset = self.queryset
if isinstance(queryset, QuerySet):
queryset = queryset.all()
elif self.model is not None:
queryset = self.model._default_manager.all()
else:
raise ImproperlyConfigured(
"%(cls)s is missing a QuerySet. Define "
"%(cls)s.model, %(cls)s.queryset, or override "
"%(cls)s.get_queryset()." % {
'cls': self.__class__.__name__
}
)
ordering = self.get_ordering()
if ordering:
if isinstance(ordering, str):
ordering = (ordering,)
queryset = queryset.order_by(*ordering)
return queryset
def http_method_not_allowed(self, request, *args, **kwargs):
logger.warning(
'Method Not Allowed (%s): %s', request.method, request.path,
extra={'status_code': 405, 'request': request}
)
return HttpResponseNotAllowed(self._allowed_methods())
Конструктор. Вызывается в URLconf; может содержать полезные дополнительные ключевые аргументы и другие вещи.
def __init__(self, **kwargs):
"""
Constructor. Called in the URLconf; can contain helpful extra
keyword arguments, and other things.
"""
# Go through keyword arguments, and either save their values to our
# instance, or raise an error.
for key, value in kwargs.items():
setattr(self, key, value)
Convert a date into a datetime when the date field is a DateTimeField. When time zone support is enabled, `date` is assumed to be in the current time zone, so that displayed items are consistent with the URL.
def _make_date_lookup_arg(self, value):
"""
Convert a date into a datetime when the date field is a DateTimeField.
When time zone support is enabled, `date` is assumed to be in the
current time zone, so that displayed items are consistent with the URL.
"""
if self.uses_datetime_field:
value = datetime.datetime.combine(value, datetime.time.min)
if settings.USE_TZ:
value = timezone.make_aware(value, timezone.get_current_timezone())
return value
Get the lookup kwargs for filtering on a single date. If the date field is a DateTimeField, we can't just filter on date_field=date because that doesn't take the time into account.
def _make_single_date_lookup(self, date):
"""
Get the lookup kwargs for filtering on a single date.
If the date field is a DateTimeField, we can't just filter on
date_field=date because that doesn't take the time into account.
"""
date_field = self.get_date_field()
if self.uses_datetime_field:
since = self._make_date_lookup_arg(date)
until = self._make_date_lookup_arg(date + datetime.timedelta(days=1))
return {
'%s__gte' % date_field: since,
'%s__lt' % date_field: until,
}
else:
# Skip self._make_date_lookup_arg, it's a no-op in this branch.
return {date_field: date}
Обрабатывает ответы на запросы для запроса HTTP OPTIONS.
def options(self, request, *args, **kwargs):
"""Handle responding to requests for the OPTIONS HTTP verb."""
response = HttpResponse()
response['Allow'] = ', '.join(self._allowed_methods())
response['Content-Length'] = '0'
return response
Разбивает запрос на страницы, если необходимо.
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)
})