from django.forms.models import ModelFormMetaclass,ModelForm
from django.template import RequestContext,loader
from django.http import Http404,HttpResponse,HttpResponseRedirect
from django.core.xheaders import populate_xheaders
from django.core.exceptions import ObjectDoesNotExist,ImproperlyConfigured
from django.utils.translation import ugettext
from django.contrib.auth.views import redirect_to_login
from django.views.generic import GenericViewError
from django.contrib import messages
def apply_extra_context(extra_context, context):
"""
Adds items from extra_context dict to context. If a value in extra_context
is callable, then it is called and the result is added to context.
"""
for key, value in extra_context.iteritems():
if callable(value):
context[key] = value()
else:
context[key] = value
def get_model_and_form_class(model, form_class):
"""
Returns a model and form class based on the model and form_class
parameters that were passed to the generic view.
If ``form_class`` is given then its associated model will be returned along
with ``form_class`` itself. Otherwise, if ``model`` is given, ``model``
itself will be returned along with a ``ModelForm`` class created from
``model``.
"""
if form_class:
return form_class._meta.model, form_class
if model:
# The inner Meta class fails if model = model is used for some reason.
tmp_model = model
# TODO: we should be able to construct a ModelForm without creating
# and passing in a temporary inner class.
class Meta:
model = tmp_model
class_name = model.__name__ + 'Form'
form_class = ModelFormMetaclass(class_name, (ModelForm,), {'Meta': Meta})
return model, form_class
raise GenericViewError("Generic view must be called with either a model or"
" form_class argument.")
def redirect(post_save_redirect, obj):
"""
Returns a HttpResponseRedirect to ``post_save_redirect``.
``post_save_redirect`` should be a string, and can contain named string-
substitution place holders of ``obj`` field names.
If ``post_save_redirect`` is None, then redirect to ``obj``'s URL returned
by ``get_absolute_url()``. If ``obj`` has no ``get_absolute_url`` method,
then raise ImproperlyConfigured.
This function is meant to handle the post_save_redirect parameter to the
``create_object`` and ``update_object`` views.
"""
if post_save_redirect:
return HttpResponseRedirect(post_save_redirect % obj.__dict__)
elif hasattr(obj, 'get_absolute_url'):
return HttpResponseRedirect(obj.get_absolute_url())
else:
raise ImproperlyConfigured(
"No URL to redirect to. Either pass a post_save_redirect"
" parameter to the generic view or define a get_absolute_url"
" method on the Model.")
def lookup_object(model, object_id, slug, slug_field):
"""
Return the ``model`` object with the passed ``object_id``. If
``object_id`` is None, then return the object whose ``slug_field``
equals the passed ``slug``. If ``slug`` and ``slug_field`` are not passed,
then raise Http404 exception.
"""
lookup_kwargs = {}
if object_id:
lookup_kwargs['%s__exact' % model._meta.pk.name] = object_id
elif slug and slug_field:
lookup_kwargs['%s__exact' % slug_field] = slug
else:
raise GenericViewError(
"Generic view must be called with either an object_id or a"
" slug/slug_field.")
try:
return model.objects.get(**lookup_kwargs)
except ObjectDoesNotExist:
raise Http404("No %s found for %s"
% (model._meta.verbose_name, lookup_kwargs))
def create_object(request, model=None, template_name=None,
template_loader=loader, extra_context=None, post_save_redirect=None,
login_required=False, context_processors=None, form_class=None):
"""
Generic object-creation function.
Templates: ``<app_label>/<model_name>_form.html``
Context:
form
the form for the object
"""
if extra_context is None: extra_context = {}
if login_required and not request.user.is_authenticated():
return redirect_to_login(request.path)
model, form_class = get_model_and_form_class(model, form_class)
if request.method == 'POST':
form = form_class(request.POST, request.FILES)
if form.is_valid():
new_object = form.save()
msg = ugettext("The %(verbose_name)s was created successfully.") %\
{"verbose_name": model._meta.verbose_name}
messages.success(request, msg, fail_silently=True)
return redirect(post_save_redirect, new_object)
else:
form = form_class()
# Create the template, context, response
if not template_name:
template_name = "%s/%s_form.html" % (model._meta.app_label, model._meta.object_name.lower())
t = template_loader.get_template(template_name)
c = RequestContext(request, {
'form': form,
}, context_processors)
apply_extra_context(extra_context, c)
return HttpResponse(t.render(c))
def update_object(request, model=None, object_id=None, slug=None,
slug_field='slug', template_name=None, template_loader=loader,
extra_context=None, post_save_redirect=None, login_required=False,
context_processors=None, template_object_name='object',
form_class=None):
"""
Generic object-update function.
Templates: ``<app_label>/<model_name>_form.html``
Context:
form
the form for the object
object
the original object being edited
"""
if extra_context is None: extra_context = {}
if login_required and not request.user.is_authenticated():
return redirect_to_login(request.path)
model, form_class = get_model_and_form_class(model, form_class)
obj = lookup_object(model, object_id, slug, slug_field)
if request.method == 'POST':
form = form_class(request.POST, request.FILES, instance=obj)
if form.is_valid():
obj = form.save()
msg = ugettext("The %(verbose_name)s was updated successfully.") %\
{"verbose_name": model._meta.verbose_name}
messages.success(request, msg, fail_silently=True)
return redirect(post_save_redirect, obj)
else:
form = form_class(instance=obj)
if not template_name:
template_name = "%s/%s_form.html" % (model._meta.app_label, model._meta.object_name.lower())
t = template_loader.get_template(template_name)
c = RequestContext(request, {
'form': form,
template_object_name: obj,
}, context_processors)
apply_extra_context(extra_context, c)
response = HttpResponse(t.render(c))
populate_xheaders(request, response, model, getattr(obj, obj._meta.pk.attname))
return response
def delete_object(request, model, post_delete_redirect, object_id=None,
slug=None, slug_field='slug', template_name=None,
template_loader=loader, extra_context=None, login_required=False,
context_processors=None, template_object_name='object'):
"""
Generic object-delete function.
The given template will be used to confirm deletetion if this view is
fetched using GET; for safty, deletion will only be performed if this
view is POSTed.
Templates: ``<app_label>/<model_name>_confirm_delete.html``
Context:
object
the original object being deleted
"""
if extra_context is None: extra_context = {}
if login_required and not request.user.is_authenticated():
return redirect_to_login(request.path)
obj = lookup_object(model, object_id, slug, slug_field)
if request.method == 'POST':
obj.delete()
msg = ugettext("The %(verbose_name)s was deleted.") %\
{"verbose_name": model._meta.verbose_name}
messages.success(request, msg, fail_silently=True)
return HttpResponseRedirect(post_delete_redirect)
else:
if not template_name:
template_name = "%s/%s_confirm_delete.html" % (model._meta.app_label, model._meta.object_name.lower())
t = template_loader.get_template(template_name)
c = RequestContext(request, {
template_object_name: obj,
}, context_processors)
apply_extra_context(extra_context, c)
response = HttpResponse(t.render(c))
populate_xheaders(request, response, model, getattr(obj, obj._meta.pk.attname))
return response
|