The package django.shortcuts
collects helper functions and classes that
“span” multiple levels of MVC. In other words, these functions/classes
introduce controlled coupling for convenience’s sake.
render()
¶render
(request, template_name, context=None, content_type=None, status=None, using=None)[source]¶Combines a given template with a given context dictionary and returns an
HttpResponse
object with that rendered text.
Django does not provide a shortcut function which returns a
TemplateResponse
because the constructor
of TemplateResponse
offers the same level
of convenience as render()
.
request
template_name
context
content_type
DEFAULT_CONTENT_TYPE
setting.status
200
.using
NAME
of a template engine to use for
loading the template.The following example renders the template myapp/index.html
with the
MIME type application/xhtml+xml:
from django.shortcuts import render
def my_view(request):
# View code here...
return render(request, 'myapp/index.html', {
'foo': 'bar',
}, content_type='application/xhtml+xml')
This example is equivalent to:
from django.http import HttpResponse
from django.template import loader
def my_view(request):
# View code here...
t = loader.get_template('myapp/index.html')
c = {'foo': 'bar'}
return HttpResponse(t.render(c, request), content_type='application/xhtml+xml')
render_to_response()
¶render_to_response
(template_name, context=None, content_type=None, status=None, using=None)[source]¶This function preceded the introduction of render()
and works
similarly except that it doesn’t make the request
available in the
response. It’s not recommended and is likely to be deprecated in the future.
redirect()
¶redirect
(to, permanent=False, *args, **kwargs)[source]¶Returns an HttpResponseRedirect
to the appropriate URL
for the arguments passed.
The arguments could be:
get_absolute_url()
function will be called.reverse()
will be
used to reverse-resolve the name.By default issues a temporary redirect; pass permanent=True
to issue a
permanent redirect.
You can use the redirect()
function in a number of ways.
By passing some object; that object’s
get_absolute_url()
method will be called
to figure out the redirect URL:
from django.shortcuts import redirect
def my_view(request):
...
object = MyModel.objects.get(...)
return redirect(object)
By passing the name of a view and optionally some positional or
keyword arguments; the URL will be reverse resolved using the
reverse()
method:
def my_view(request):
...
return redirect('some-view-name', foo='bar')
By passing a hardcoded URL to redirect to:
def my_view(request):
...
return redirect('/some/url/')
This also works with full URLs:
def my_view(request):
...
return redirect('https://example.com/')
By default, redirect()
returns a temporary redirect. All of the above
forms accept a permanent
argument; if set to True
a permanent redirect
will be returned:
def my_view(request):
...
object = MyModel.objects.get(...)
return redirect(object, permanent=True)
get_object_or_404()
¶get_object_or_404
(klass, *args, **kwargs)[source]¶Calls get()
on a given model manager,
but it raises Http404
instead of the model’s
DoesNotExist
exception.
The following example gets the object with the primary key of 1 from
MyModel
:
from django.shortcuts import get_object_or_404
def my_view(request):
my_object = get_object_or_404(MyModel, pk=1)
This example is equivalent to:
from django.http import Http404
def my_view(request):
try:
my_object = MyModel.objects.get(pk=1)
except MyModel.DoesNotExist:
raise Http404("No MyModel matches the given query.")
The most common use case is to pass a Model
, as
shown above. However, you can also pass a
QuerySet
instance:
queryset = Book.objects.filter(title__startswith='M')
get_object_or_404(queryset, pk=1)
The above example is a bit contrived since it’s equivalent to doing:
get_object_or_404(Book, title__startswith='M', pk=1)
but it can be useful if you are passed the queryset
variable from somewhere
else.
Finally, you can also use a Manager
. This is useful
for example if you have a
custom manager:
get_object_or_404(Book.dahl_objects, title='Matilda')
You can also use
related managers
:
author = Author.objects.get(name='Roald Dahl')
get_object_or_404(author.book_set, title='Matilda')
Note: As with get()
, a
MultipleObjectsReturned
exception
will be raised if more than one object is found.
get_list_or_404()
¶get_list_or_404
(klass, *args, **kwargs)[source]¶Returns the result of filter()
on a
given model manager cast to a list, raising Http404
if
the resulting list is empty.
The following example gets all published objects from MyModel
:
from django.shortcuts import get_list_or_404
def my_view(request):
my_objects = get_list_or_404(MyModel, published=True)
This example is equivalent to:
from django.http import Http404
def my_view(request):
my_objects = list(MyModel.objects.filter(published=True))
if not my_objects:
raise Http404("No MyModel matches the given query.")
Jun 09, 2017