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Diffstat (limited to 'webapp/django/views/generic/create_update.py')
| -rw-r--r-- | webapp/django/views/generic/create_update.py | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/webapp/django/views/generic/create_update.py b/webapp/django/views/generic/create_update.py new file mode 100644 index 0000000000..634fb1bdcd --- /dev/null +++ b/webapp/django/views/generic/create_update.py @@ -0,0 +1,210 @@ +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 + + +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 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() + if request.user.is_authenticated(): + request.user.message_set.create(message=ugettext("The %(verbose_name)s was created successfully.") % {"verbose_name": model._meta.verbose_name}) + 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() + if request.user.is_authenticated(): + request.user.message_set.create(message=ugettext("The %(verbose_name)s was updated successfully.") % {"verbose_name": model._meta.verbose_name}) + 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() + if request.user.is_authenticated(): + request.user.message_set.create(message=ugettext("The %(verbose_name)s was deleted.") % {"verbose_name": model._meta.verbose_name}) + 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 |