Base views

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 inheritence 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

class django.views.generic.base.View

The master class-based base view. All other class-based views inherit from this base class.

Method Flowchart

  1. dispatch()
  2. http_method_not_allowed()
  3. options()

Example views.py:

from django.http import HttpResponse
from django.views.generic import View

class MyView(View):

    def get(self, request, *args, **kwargs):
        return HttpResponse('Hello, World!')

Example urls.py:

from django.conf.urls import patterns, url

from myapp.views import MyView

urlpatterns = patterns('',
    url(r'^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', 'delete', 'head', 'options', 'trace']

Methods

classmethod as_view(**initkwargs)

Returns a callable view that takes a request and returns a response:

response = MyView.as_view()(request)
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.

The default implementation also sets request, args and kwargs as instance variables, so any method on the view can know the full details of the request that was made to invoke the view.

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 list of the allowed HTTP method names for the view.

TemplateView

class django.views.generic.base.TemplateView

Renders a given template, with the context containing parameters captured in the URL.

The context used to be populated with a {{ params }} dictionary of the parameters captured in the URL. Now those parameters are first-level context variables.

Ancestors (MRO)

This view inherits methods and attributes from the following views:

Method Flowchart

  1. dispatch()
  2. http_method_not_allowed()
  3. get_context_data()

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(HomePageView, self).get_context_data(**kwargs)
        context['latest_articles'] = Article.objects.all()[:5]
        return context

Example urls.py:

from django.conf.urls import patterns, url

from myapp.views import HomePageView

urlpatterns = patterns('',
    url(r'^$', HomePageView.as_view(), name='home'),
)

Context

  • params: The dictionary of keyword arguments captured from the URL pattern that served the view.

RedirectView

class 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

  1. dispatch()
  2. http_method_not_allowed()
  3. get_redirect_url()

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

    def get_redirect_url(self, pk):
        article = get_object_or_404(Article, pk=pk)
        article.update_counter()
        return reverse('product_detail', args=(pk,))

Example urls.py:

from django.conf.urls import patterns, url
from django.views.generic.base import RedirectView

from article.views import ArticleCounterRedirectView

urlpatterns = patterns('',

    url(r'r^(?P<pk>\d+)/$', ArticleCounterRedirectView.as_view(), name='article-counter'),
    url(r'^go-to-django/$', RedirectView.as_view(url='http://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.

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 True.

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(**kwargs)

Constructs the target URL for redirection.

The default implementation uses url as a starting string, performs expansion of % parameters in that string, as well as the appending of query string if requested by query_string. Subclasses may implement any behavior they wish, as long as the method returns a redirect-ready URL string.