fix for #7. implementing a comment_removed signal for other apps to l…

…isten for. comment_removed is sent when a comment is deleted or when a comment's is_removed attribute is flipped from True to False.

ella_comments/listing_handlers.py

@@ -38,17 +38,6 @@ class MostCommentedListingHandler(CommentListingHandler, RedisListingHandler):
 class LastCommentedListingHandler(CommentListingHandler, RedisListingHandler):
     PREFIX = 'lastcom'
 
-def comment_pre_save(instance, **kwargs):
-    if instance.pk:
-        try:
-            old_instance = instance.__class__._default_manager.get(pk=instance.pk)
-        except instance.__class__.DoesNotExist:
-            return
-        instance.__pub_info = {
-            'is_public': old_instance.is_public,
-            'is_removed': old_instance.is_removed,
-        }
-
 def comment_post_save(instance, **kwargs):
     if hasattr(instance, '__pub_info'):
         is_public = instance.is_public and not instance.is_removed
@@ -138,13 +127,12 @@ def comment_posted(comment, **kwargs):
 def connect_signals():
     from django.contrib.comments.signals import comment_was_posted
     from ella.core.signals import content_published, content_unpublished
-    from django.db.models.signals import pre_save, post_save
+    from django.db.models.signals import post_save
     content_published.connect(publishable_published)
     content_unpublished.connect(publishable_unpublished)
 
     comment_was_posted.connect(comment_posted)
 
-    pre_save.connect(comment_pre_save, sender=comments.get_model())
     post_save.connect(comment_post_save, sender=comments.get_model())
 
 if client:

ella_comments/models.py

@@ -1,6 +1,7 @@
 import operator
 
 from django.db import models
+from django.db.models.signals import pre_save, post_save, post_delete
 from django.contrib import comments
 from django.contrib.contenttypes.models import ContentType
 from django.utils.translation import ugettext_lazy as _
@@ -13,6 +14,7 @@
 from threadedcomments.models import PATH_DIGITS
 
 from ella_comments.listing_handlers import COMCOUNT_KEY
+from ella_comments.signals import comment_removed
 
 DEFAULT_COMMENT_OPTIONS = {
     'blocked': False,
@@ -163,3 +165,27 @@ class Meta:
     def __unicode__(self):
         return u"%s: %s" % (_("Comment Options"), self.target)
 
+# signal handlers for sending comment_removed signals
+def comment_pre_save(instance, **kwargs):
+    if instance.pk:
+        try:
+            old_instance = instance.__class__._default_manager.get(pk=instance.pk)
+        except instance.__class__.DoesNotExist:
+            return
+        instance.__pub_info = {
+            'is_public': old_instance.is_public,
+            'is_removed': old_instance.is_removed,
+        }
+
+def comment_post_save(instance, **kwargs):
+    if hasattr(instance, '__pub_info'):
+        # if this is a newly removed comment, send the comment_removed signal
+        if not instance.__pub_info['is_removed'] and instance.is_removed:
+            comment_removed.send(sender=instance.__class__, comment=instance)
+
+def comment_post_delete(instance, **kwargs):
+    comment_removed.send(sender=instance.__class__, comment=instance)
+
+pre_save.connect(comment_pre_save, sender=comments.get_model())
+post_save.connect(comment_post_save, sender=comments.get_model())
+post_delete.connect(comment_post_delete, sender=comments.get_model())

ella_comments/signals.py

@@ -0,0 +1,3 @@
+from django.dispatch import Signal
+
+comment_removed = Signal(providing_args=['comment'])

test_ella_comments/test_signals.py

@@ -0,0 +1,49 @@
+from django.test import TestCase
+
+from ella.utils.test_helpers import create_basic_categories, create_and_place_a_publishable
+
+from test_ella_comments.helpers import create_comment
+from ella_comments.signals import comment_removed
+
+from nose import tools
+
+SIGNALED_COMMENT = None
+def handle_signal(comment, **kwargs):
+    global SIGNALED_COMMENT
+    SIGNALED_COMMENT = comment.id
+
+def reset_signaled_comment():
+    global SIGNALED_COMMENT
+    SIGNALED_COMMENT = None
+
+class TestSignals(TestCase):
+    def setUp(self):
+        super(TestSignals, self).setUp()
+        reset_signaled_comment()
+        comment_removed.connect(handle_signal)
+        create_basic_categories(self)
+        create_and_place_a_publishable(self)
+        self.comment = create_comment(self.publishable, self.publishable.content_type)
+
+    def tearDown(self):
+        comment_removed.disconnect(handle_signal)
+        reset_signaled_comment()
+        super(TestSignals, self).tearDown()
+
+    def test_deleted_comment_sends_signal(self):
+        id = self.comment.id
+        tools.assert_equals(SIGNALED_COMMENT, None)
+        self.comment.delete()
+        tools.assert_equals(SIGNALED_COMMENT, id)
+
+    def test_moderated_comment_sends_signal(self):
+        id = self.comment.id
+        tools.assert_equals(SIGNALED_COMMENT, None)
+        self.comment.is_removed = True
+        self.comment.save()
+        tools.assert_equals(SIGNALED_COMMENT, id)
+
+    def test_general_comment_save_doesnt_send_signal(self):
+        tools.assert_equals(SIGNALED_COMMENT, None)
+        self.comment.save()
+        tools.assert_equals(SIGNALED_COMMENT, None)