Added support for purging URLs on deleting specific models instance (c…

…loses #5)

Now it's possible to do something like this (example based on flatpages):

for f in FlatPage.objects.all():
    purge(f.url).on_save(f)
    purge(f.url).on_delete(f)

roan/__init__.py

@@ -20,24 +20,23 @@ def purger(sender, instance, **kw):
                 self.requests.get(purge_url)
 
         model = type(obj)
-        signal.connect(purger, sender=model, weak=False, dispatch_uid='purge_%s_on_save_%s' % (self.url, model._meta.verbose_name))
+        getattr(signals, signal).connect(purger, sender=model, weak=False, dispatch_uid='purge_%s_%s_%s' % (self.url, signal, model._meta.verbose_name))
 
     def _purge_class(self, model, signal):
         def purger(sender, **kw):
             purge_url = self.purge_url + self.url
             self.requests.get(purge_url)
 
-        signal.connect(purger, sender=model, weak=False, dispatch_uid='purge_%s_on_save_%s' % (self.url, model._meta.verbose_name))
+        getattr(signals, signal).connect(purger, sender=model, weak=False, dispatch_uid='purge_%s_%s_%s' % (self.url, signal, model._meta.verbose_name))
 
     def on_save(self, obj):
         if isinstance(obj, django_models.Model):
-            self._purge_instance(obj, signals.post_save)
+            self._purge_instance(obj, "post_save")
         else:
-            self._purge_class(obj, signals.post_save)
+            self._purge_class(obj, "post_save")
 
-    def on_delete(self, model):
-        def purger(sender, **kw):
-            purge_url = self.purge_url + self.url
-            self.requests.get(purge_url)
-
-        signals.post_delete.connect(purger, sender=model, weak=False, dispatch_uid='purge_%s_on_delete_%s' % (self.url, model._meta.verbose_name))
+    def on_delete(self, obj):
+        if isinstance(obj, django_models.Model):
+            self._purge_instance(obj, "post_delete")
+        else:
+            self._purge_class(obj, "post_delete")

roan/tests/test_purge.py

@@ -55,12 +55,12 @@ def test_purge_should_receive_and_store_url(self):
 
     def test_purge_should_connect_to_save_signal_of_a_model_with_unique_dispatch_uid(self):
         roan.purge("/").on_save(models.Poll)
-        expected_uid = "purge_/_on_save_%s" % models.Poll._meta.verbose_name
+        expected_uid = "purge_/_post_save_%s" % models.Poll._meta.verbose_name
         uuids = [r[0][0] for r in signals.post_save.receivers]
         self.assertIn(expected_uid, uuids)
 
     def test_purge_should_connect_to_save_signal_without_a_weak_reference(self):
-        uid = "purge_/_on_save_%s" % models.Poll._meta.verbose_name
+        uid = "purge_/_post_save_%s" % models.Poll._meta.verbose_name
         roan.purge("/").on_save(models.Poll)
         f = [r[1] for r in signals.post_save.receivers if r[0][0] == uid][0]
         self.assertNotIsInstance(f, weakref.ref)
@@ -76,12 +76,12 @@ def test_when_the_model_is_saved_the_url_should_be_purged(self):
 
     def test_purge_should_connect_to_delete_signal_of_a_model_with_unique_dispatch_uid(self):
         roan.purge("/").on_delete(models.Poll)
-        expected_uid = "purge_/_on_delete_%s" % models.Poll._meta.verbose_name
+        expected_uid = "purge_/_post_delete_%s" % models.Poll._meta.verbose_name
         uuids = [r[0][0] for r in signals.post_delete.receivers]
         self.assertIn(expected_uid, uuids)
 
     def test_purge_should_to_delete_sginal_without_a_weak_reference(self):
-        uid = "purge_/_on_delete_%s" % models.Poll._meta.verbose_name
+        uid = "purge_/_post_delete_%s" % models.Poll._meta.verbose_name
         roan.purge("/").on_delete(models.Poll)
         f = [r[1] for r in signals.post_delete.receivers if r[0][0] == uid][0]
         self.assertNotIsInstance(f, weakref.ref)
@@ -116,5 +116,28 @@ def test_should_not_purge_on_saving_an_object_that_was_not_connected_to_the_url(
         p.requests = mocks.RequestsMock(200, purge_url)
         p.on_save(poll)
 
-        models.Poll.objects.create(title=u'What is your favorite car?')
+        models.Poll.objects.get_or_create(title=u'What is your favorite car?')
+        self.assertFalse(p.requests.done)
+
+    def test_should_be_able_to_purge_an_url_on_delete_a_model_instance(self):
+        poll, created = models.Poll.objects.get_or_create(title=u'Do you think Roan should work?')
+
+        purge_url = "http://localhost/purge/polls/%d" % poll.id
+        p = roan.purge("/polls/%d" % poll.id)
+        p.requests = mocks.RequestsMock(200, purge_url)
+        p.on_delete(poll)
+
+        poll.delete()
+        self.assertTrue(p.requests.done)
+
+    def test_should_not_purge_on_deleting_an_object_that_was_not_connected_to_the_url(self):
+        poll, created = models.Poll.objects.get_or_create(title=u'Do you think Roan should work?')
+        other, created = models.Poll.objects.get_or_create(title=u'What is your favorite car?')
+
+        purge_url = "http://localhost/purge/polls/%d" % poll.id
+        p = roan.purge("/polls/%d" % poll.id)
+        p.requests = mocks.RequestsMock(200, purge_url)
+        p.on_delete(poll)
+
+        other.delete()
         self.assertFalse(p.requests.done)