Add crud views with pluggable view mixin

- idea for this is to quickly standup a staff
  admin for announcements and provide your own
  authentication rules via the mixin.

announcements/forms.py

@@ -0,0 +1,18 @@
+from django import forms
+
+from announcements.models import Announcement
+
+
+class AnnouncementForm(forms.ModelForm):
+
+    class Meta:
+        model = Announcement
+        fields = [
+            "title",
+            "content",
+            "site_wide",
+            "members_only",
+            "dismissal_type",
+            "publish_start",
+            "publish_end"
+        ]

announcements/mixins.py

@@ -0,0 +1,30 @@
+from django.conf import settings
+from django.utils.importlib import import_module
+
+
+def _resolve(mixin_setting):
+    if isinstance(mixin_setting, basestring):
+        try:
+            mod_name, klass_name = mixin_setting.rsplit(".", 1)
+        except ValueError:
+            raise Exception("Improperly configured.")
+        try:
+            mod = import_module(mod_name)
+        except ImportError:
+            raise Exception("Could not import %s" % mod_name)
+        try:
+            klass = getattr(mod, klass_name)
+        except AttributeError:
+            raise Exception("The module '%s' does not contain '%s'." % (mod_name, klass_name))
+        mixin_setting = klass
+    return mixin_setting
+
+
+class DefaultProtectedMixin(object):
+
+    pass
+
+
+ProtectedMixin = _resolve(
+    getattr(settings, "ANNOUNCEMENTS_PROTECTED_MIXIN", DefaultProtectedMixin)
+)

announcements/signals.py

@@ -0,0 +1,6 @@
+import django.dispatch
+
+
+announcement_created = django.dispatch.Signal(providing_args=["announcement", "request"])
+announcement_updated = django.dispatch.Signal(providing_args=["announcement", "request"])
+announcement_deleted = django.dispatch.Signal(providing_args=["announcement", "request"])

announcements/urls.py

@@ -1,7 +1,15 @@
 from django.conf.urls.defaults import *
 
+from announcements.views import detail, dismiss
+from announcements.views import CreateAnnouncementView, UpdateAnnouncementView
+from announcements.views import DeleteAnnouncementView, AnnouncementListView
 
 urlpatterns = patterns("",
-    url(r"^(?P<pk>\d+)/$", "announcements.views.detail", name="announcements_detail"),
-    url(r"^(?P<pk>\d+)/hide/$", "announcements.views.dismiss", name="announcement_dismiss")
+    url(r"announcement/(?P<pk>\d+)/$", detail, name="announcements_detail"),
+    url(r"announcement/(?P<pk>\d+)/hide/$", dismiss, name="announcement_dismiss"),
+
+    url(r"announcement/create/$", CreateAnnouncementView.as_view(), name="announcements_create"),
+    url(r"announcement/(?P<pk>\d+)/update/$", UpdateAnnouncementView.as_view(), name="announcements_update"),
+    url(r"announcement/(?P<pk>\d+)/delete/$", DeleteAnnouncementView.as_view(), name="announcements_delete"),
+    url(r"", AnnouncementListView.as_view(), name="announcements_list"),
 )

announcements/views.py

@@ -1,8 +1,14 @@
+from django.core.urlresolvers import reverse
 from django.http import HttpResponse, HttpResponseNotAllowed
 from django.shortcuts import get_object_or_404
 from django.template.response import TemplateResponse
+from django.views.generic.edit import CreateView, UpdateView, DeleteView
+from django.views.generic.list import ListView
 
+from announcements.forms import AnnouncementForm
+from announcements.mixins import ProtectedMixin
 from announcements.models import Announcement
+from announcements.signals import announcement_created, announcement_updated, announcement_deleted
 
 
 def dismiss(request, pk):
@@ -30,3 +36,66 @@ def detail(request, pk):
     return TemplateResponse(request, "announcements/detail.html", {
         "announcement": announcement
     })
+
+
+class CreateAnnouncementView(CreateView, ProtectedMixin):
+
+    model = Announcement
+    form_class = AnnouncementForm
+
+    def form_valid(self, form):
+        self.object = form.save(commit=False)
+        self.object.creator = self.request.user
+        self.object.save()
+
+        announcement_created.send(
+            sender=self.object,
+            announcement=self.object,
+            request=self.request
+        )
+        return super(CreateAnnouncementView, self).form_valid(form)
+
+    def get_success_url(self):
+        return reverse("announcements_list")
+
+
+class UpdateAnnouncementView(UpdateView, ProtectedMixin):
+
+    model = Announcement
+    form_class = AnnouncementForm
+
+    def form_valid(self, form):
+        response = super(UpdateAnnouncementView, self).form_valid(form)
+        announcement_updated.send(
+            sender=self.object,
+            announcement=self.object,
+            request=self.request
+        )
+        return response
+
+    def get_success_url(self):
+        return reverse("announcements_list")
+
+
+class DeleteAnnouncementView(DeleteView, ProtectedMixin):
+
+    model = Announcement
+
+    def form_valid(self, form):
+        response = super(DeleteAnnouncementView, self).form_valid(form)
+        announcement_deleted.send(
+            sender=self.object,
+            announcement=self.object,
+            request=self.request
+        )
+        return response
+
+    def get_success_url(self):
+        return reverse("announcements_list")
+
+
+class AnnouncementListView(ListView, ProtectedMixin):
+
+    model = Announcement
+    queryset = Announcement.objects.all().order_by("-creation_date")
+    paginate_by = 50