The document discusses Django's class-based generic views. It provides an overview of common class-based views like TemplateView, ListView, DetailView, CreateView, UpdateView, and DeleteView. It also compares implementing views as functions versus classes, noting that classes provide code reuse through inheritance and method overriding.

1. "Джанго сделал для гитары больше, чем
кто-либо в джазе. Его стиль игры был не
похож ни на один другой, благодаря ему
джаз стал другим. Будет еще много
выдающихся гитаристов, но никогда не
будет другого Рейнхарда. Я просто
уверен в этом".
Стефан Грапелли, 1954

2. Class Based Generic Views
Django meetup 3

3. Function Based
def meetup_edit(request, pk):
meetup = get_object_or_404(Meetup, pk = pk)
if request.method == 'POST':
form = MeetupForm(request.POST, request.FILES)
if form.is_valid():
form.save()
return HttpResponseRedirect('/thanks/')
else:
return render_to_response('meetup.html', {'form': form})
else:
form = MeetupForm(instance = meetup)
return render_to_response('meetup.html', {'form': form})

4. Class Based
class MeetupUpdateView(UpdateView):
model = Meetup
template_name = ‘meetup.html’
form_class = MeetupForm
success_url = ‘/thanks/’

5. Class Based Views:
• TemplateView
• ListView
• DetailView
• CreateView
• UpdateView
• DeleteView
• RedirectView
• YearArchiveView, MonthArchiveView,
WeekArchiveView, DayArchiveView,
TodayArchiveView

6. Реализация
class TemplateView(TemplateResponseMixin, ContextMixin, View):
def get(self, request, *args, **kwargs):
context = self.get_context_data(params = kwargs)
return self.render_to_response(context)
class ListView(MultipleObjectTemplateResponseMixin,BaseListView):
pass
class DetailView(SingleObjectTemplateResponseMixin, BaseDetailView):
pass

7. Реализация
class CreateView(SingleObjectTemplateResponseMixin, BaseCreateView):
template_name_suffix = '_form'
class UpdateView(SingleObjectTemplateResponseMixin, BaseUpdateView):
template_name_suffix = '_form'
class DeleteView(SingleObjectTemplateResponseMixin, BaseDeleteView):
template_name_suffix = '_confirm_delete'

8. 3 основных требования к view в Django:
• Должны быть callable объектом
• Должны принимать НttpRequest
• Должны возвращать HttpResponse

9. # urls.py
from django.conf.urls import patterns, url
from some_app.views import AboutView
urlpatterns = patterns('',
url(r'^/', AboutView.as_view(), name=”some_app_about”),
)

10. @classonlymethod
def as_view(cls, **initkwargs):
def view(request, *args, **kwargs):
self = cls(**initkwargs)
return self.dispatch(request, *args, **kwargs)
return view

11. @method_decorator(login_required)
def dispatch(self, request, *args, **kwargs):
handler = getattr(self, request.method.lower())
self.request = request
self.args = args
self.kwargs = kwargs
return handler(request, *args, **kwargs)

12. def get(self, request, *args, **kwargs):
context = self.get_context_data(params=kwargs)
return self.render_to_response(context)
def post(self, request, *args, **kwargs):
form_class = self.get_form_class()
form = self.get_form(form_class)
if form.is_valid():
return self.form_valid(form)
else:
return self.form_invalid(form)

13. def get_context_data(self, **kwargs):
return kwargs
def render_to_response(self, context, **kw):
return self.response_class(
request = self.request,
template = self.get_template_names(),
context = context,
**kw)

14. SUCCESS!

15. http://ccbv.co.uk/

16. TemplateView

17. as_view() исходный код

18. https://github.com/FZambia/django-class-
based-vs-function-based

19. 1000 GET запросов, 1000 POST запросов:
Class Based View GET:
11.6180129051
.
Class Based View POST:
15.6457400322
.
Function Based View GET:
11.2678151131
.
Function Based View POST:
15.1721260548
.
----------------------------------------------------------------------
Ran 4 tests in 56.563s

20. Полезные ссылки:
•https://github.com/django/django/tree/master/django/views/g
eneric
• http://habrahabr.ru/post/136784/
• http://habrahabr.ru/post/137168/
• http://softwaremaniacs.org/blog/2011/10/06/class-based-
generic-views/
• http://kimavr.name/blog/2011/9/2/7/
• https://github.com/brack3t/django-braces
• https://github.com/lig/django-supergeneric
• https://code.djangoproject.com/ticket/6735