The following three classes provide much of the functionality needed to create Django views. You may think of them as parent views, which can be used by themselves or inherited from. They may not provide all the capabilities required for projects, in which case there are Mixins and Generic class-based views.
Many of Django’s built-in class-based views inherit from other class-based views or various mixins. Because this inheritance chain is very important, the ancestor classes are documented under the section title of Ancestors (MRO). MRO is an acronym for Method Resolution Order.
View
¶django.views.generic.base.
View
¶The master class-based base view. All other class-based views inherit from
this base class. It isn’t strictly a generic view and thus can also be
imported from django.views
.
Method Flowchart
Example views.py:
from django.http import HttpResponse
from django.views import View
class MyView(View):
def get(self, request, *args, **kwargs):
return HttpResponse('Hello, World!')
Example urls.py:
from django.urls import path
from myapp.views import MyView
urlpatterns = [
path('mine/', MyView.as_view(), name='my-view'),
]
Attributes
http_method_names
¶The list of HTTP method names that this view will accept.
Default:
['get', 'post', 'put', 'patch', 'delete', 'head', 'options', 'trace']
Methods
as_view
(**initkwargs)¶Returns a callable view that takes a request and returns a response:
response = MyView.as_view()(request)
The returned view has view_class
and view_initkwargs
attributes.
When the view is called during the request/response cycle, the
setup()
method assigns the HttpRequest
to
the view’s request
attribute, and any positional and/or keyword
arguments captured from the URL pattern to the args
and kwargs
attributes, respectively. Then dispatch()
is called.
setup
(request, *args, **kwargs)¶Performs key view initialization prior to dispatch()
.
If overriding this method, you must call super()
.
dispatch
(request, *args, **kwargs)¶The view
part of the view – the method that accepts a request
argument plus arguments, and returns a HTTP response.
The default implementation will inspect the HTTP method and attempt to
delegate to a method that matches the HTTP method; a GET
will be
delegated to get()
, a POST
to post()
, and so on.
By default, a HEAD
request will be delegated to get()
.
If you need to handle HEAD
requests in a different way than GET
,
you can override the head()
method. See
Supporting other HTTP methods for an example.
http_method_not_allowed
(request, *args, **kwargs)¶If the view was called with a HTTP method it doesn’t support, this method is called instead.
The default implementation returns HttpResponseNotAllowed
with a
list of allowed methods in plain text.
options
(request, *args, **kwargs)¶Handles responding to requests for the OPTIONS HTTP verb. Returns a
response with the Allow
header containing a list of the view’s
allowed HTTP method names.
TemplateView
¶django.views.generic.base.
TemplateView
¶Renders a given template, with the context containing parameters captured in the URL.
Ancestors (MRO)
This view inherits methods and attributes from the following views:
django.views.generic.base.TemplateResponseMixin
django.views.generic.base.ContextMixin
django.views.generic.base.View
Method Flowchart
Example views.py:
from django.views.generic.base import TemplateView
from articles.models import Article
class HomePageView(TemplateView):
template_name = "home.html"
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
context['latest_articles'] = Article.objects.all()[:5]
return context
Example urls.py:
from django.urls import path
from myapp.views import HomePageView
urlpatterns = [
path('', HomePageView.as_view(), name='home'),
]
Context
ContextMixin
) with
the keyword arguments captured from the URL pattern that served the view.extra_context
keyword
argument for as_view()
.RedirectView
¶django.views.generic.base.
RedirectView
¶Redirects to a given URL.
The given URL may contain dictionary-style string formatting, which will be
interpolated against the parameters captured in the URL. Because keyword
interpolation is always done (even if no arguments are passed in), any
"%"
characters in the URL must be written as "%%"
so that Python
will convert them to a single percent sign on output.
If the given URL is None
, Django will return an HttpResponseGone
(410).
Ancestors (MRO)
This view inherits methods and attributes from the following view:
Method Flowchart
Example views.py:
from django.shortcuts import get_object_or_404
from django.views.generic.base import RedirectView
from articles.models import Article
class ArticleCounterRedirectView(RedirectView):
permanent = False
query_string = True
pattern_name = 'article-detail'
def get_redirect_url(self, *args, **kwargs):
article = get_object_or_404(Article, pk=kwargs['pk'])
article.update_counter()
return super().get_redirect_url(*args, **kwargs)
Example urls.py:
from django.urls import path
from django.views.generic.base import RedirectView
from article.views import ArticleCounterRedirectView, ArticleDetailView
urlpatterns = [
path('counter/<int:pk>/', ArticleCounterRedirectView.as_view(), name='article-counter'),
path('details/<int:pk>/', ArticleDetailView.as_view(), name='article-detail'),
path('go-to-django/', RedirectView.as_view(url='https://www.djangoproject.com/'), name='go-to-django'),
]
Attributes
url
¶The URL to redirect to, as a string. Or None
to raise a 410 (Gone)
HTTP error.
pattern_name
¶The name of the URL pattern to redirect to. Reversing will be done using the same args and kwargs as are passed in for this view.
permanent
¶Whether the redirect should be permanent. The only difference here is
the HTTP status code returned. If True
, then the redirect will use
status code 301. If False
, then the redirect will use status code
302. By default, permanent
is False
.
query_string
¶Whether to pass along the GET query string to the new location. If
True
, then the query string is appended to the URL. If False
,
then the query string is discarded. By default, query_string
is
False
.
Methods
get_redirect_url
(*args, **kwargs)¶Constructs the target URL for redirection.
The args
and kwargs
arguments are positional and/or keyword
arguments captured from the URL pattern, respectively.
The default implementation uses url
as a starting
string and performs expansion of %
named parameters in that string
using the named groups captured in the URL.
If url
is not set, get_redirect_url()
tries to reverse the
pattern_name
using what was captured in the URL (both named and
unnamed groups are used).
If requested by query_string
, it will also append the query
string to the generated URL.
Subclasses may implement any behavior they wish, as long as the method
returns a redirect-ready URL string.
Jul 27, 2022