django1/docs/shortcuts.txt

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=========================
Django shortcut functions
=========================
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_to_response()``
========================
``django.shortcuts.render_to_response`` renders a given template with a given
context dictionary and returns an ``HttpResponse`` object with that rendered
text.
Required arguments
------------------
``template``
The full name of a template to use.
Optional arguments
------------------
``context``
A dictionary of values to add to the template context. By default, this
is an empty dictionary. If a value in the dictionary is callable, the
view will call it just before rendering the template.
``mimetype``
**New in Django development version:** The MIME type to use for the
resulting document. Defaults to the value of the ``DEFAULT_CONTENT_TYPE``
setting.
Example
-------
The following example renders the template ``myapp/index.html`` with the
MIME type ``application/xhtml+xml``::
from django.shortcuts import render_to_response
def my_view(request):
# View code here...
return render_to_response('myapp/index.html', {"foo": "bar"},
mimetype="application/xhtml+xml")
This example is equivalent to::
from django.http import HttpResponse
from django.template import Context, loader
def my_view(request):
# View code here...
t = loader.get_template('myapp/template.html')
c = Context({'foo': 'bar'})
r = HttpResponse(t.render(c),
mimetype="application/xhtml+xml")
.. _an HttpResponse object: ../request_response/#httpresponse-objects
``get_object_or_404``
=====================
``django.shortcuts.get_object_or_404`` calls `get()`_ on a given model
manager, but it raises ``django.http.Http404`` instead of the model's
``DoesNotExist`` exception.
Required arguments
------------------
``klass``
A ``Model``, ``Manager`` or ``QuerySet`` instance from which to get the
object.
``**kwargs``
Lookup parameters, which should be in the format accepted by ``get()`` and
``filter()``.
Example
-------
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
Note: As with ``get()``, an ``MultipleObjectsReturned`` exception will be
raised if more than one object is found.
.. _get(): ../db-api/#get-kwargs
``get_list_or_404``
===================
``django.shortcuts.get_list_or_404`` returns the result of `filter()`_ on a
given model manager, raising ``django.http.Http404`` if the resulting list is
empty.
Required arguments
------------------
``klass``
A ``Model``, ``Manager`` or ``QuerySet`` instance from which to get the
object.
``**kwargs``
Lookup parameters, which should be in the format accepted by ``get()`` and
``filter()``.
Example
-------
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 = MyModel.objects.filter(published=True)
if not my_objects:
raise Http404
.. _filter(): ../db-api/#filter-kwargs