Merge branch 'main' into inbox-refactor

bookwyrm/models/relationship.py

@@ -1,8 +1,7 @@
 ''' defines relationships between users '''
 from django.apps import apps
-from django.db import models, transaction
+from django.db import models, transaction, IntegrityError
 from django.db.models import Q
-from django.dispatch import receiver
 
 from bookwyrm import activitypub
 from .activitypub_mixin import ActivitypubMixin, ActivityMixin
@@ -61,15 +60,26 @@ class UserFollows(ActivityMixin, UserRelationship):
     ''' Following a user '''
     status = 'follows'
 
-    def save(self, *args, **kwargs):
-        ''' never broadcast a creation (that's handled by "accept"), only a
-            deletion (an unfollow, as opposed to "reject" and undo pending) '''
-        super().save(*args, broadcast=False, **kwargs)
-
     def to_activity(self):
         ''' overrides default to manually set serializer '''
         return activitypub.Follow(**generate_activity(self))
 
+    def save(self, *args, **kwargs):
+        ''' really really don't let a user follow someone who blocked them '''
+        # blocking in either direction is a no-go
+        if UserBlocks.objects.filter(
+                Q(
+                    user_subject=self.user_subject,
+                    user_object=self.user_object,
+                ) | Q(
+                    user_subject=self.user_object,
+                    user_object=self.user_subject,
+                )
+            ).exists():
+            raise IntegrityError()
+        # don't broadcast this type of relationship -- accepts and requests
+        # are handled by the UserFollowRequest model
+        super().save(*args, broadcast=False, **kwargs)
 
     @classmethod
     def from_request(cls, follow_request):
@@ -88,24 +98,23 @@ class UserFollowRequest(ActivitypubMixin, UserRelationship):
 
     def save(self, *args, broadcast=True, **kwargs):
         ''' make sure the follow or block relationship doesn't already exist '''
-        try:
-            UserFollows.objects.get(
+        # don't create a request if a follow already exists
+        if UserFollows.objects.filter(
                 user_subject=self.user_subject,
                 user_object=self.user_object,
-            )
-            # blocking in either direction is a no-go
-            UserBlocks.objects.get(
-                user_subject=self.user_subject,
-                user_object=self.user_object,
-            )
-            UserBlocks.objects.get(
-                user_subject=self.user_object,
-                user_object=self.user_subject,
-            )
-            return
-        except (UserFollows.DoesNotExist, UserBlocks.DoesNotExist):
-            pass
-
+            ).exists():
+            raise IntegrityError()
+        # blocking in either direction is a no-go
+        if UserBlocks.objects.filter(
+                Q(
+                    user_subject=self.user_subject,
+                    user_object=self.user_object,
+                ) | Q(
+                    user_subject=self.user_object,
+                    user_object=self.user_subject,
+                )
+            ).exists():
+            raise IntegrityError()
         super().save(*args, **kwargs)
 
         if broadcast and self.user_subject.local and not self.user_object.local:
@@ -160,20 +169,15 @@ class UserBlocks(ActivityMixin, UserRelationship):
     status = 'blocks'
     activity_serializer = activitypub.Block
 
+    def save(self, *args, **kwargs):
+        ''' remove follow or follow request rels after a block is created '''
+        super().save(*args, **kwargs)
 
-@receiver(models.signals.post_save, sender=UserBlocks)
-#pylint: disable=unused-argument
-def execute_after_save(sender, instance, created, *args, **kwargs):
-    ''' remove follow or follow request rels after a block is created '''
-    UserFollows.objects.filter(
-        Q(user_subject=instance.user_subject,
-          user_object=instance.user_object) | \
-        Q(user_subject=instance.user_object,
-          user_object=instance.user_subject)
-    ).delete()
-    UserFollowRequest.objects.filter(
-        Q(user_subject=instance.user_subject,
-          user_object=instance.user_object) | \
-        Q(user_subject=instance.user_object,
-          user_object=instance.user_subject)
-    ).delete()
+        UserFollows.objects.filter(
+            Q(user_subject=self.user_subject, user_object=self.user_object) | \
+            Q(user_subject=self.user_object, user_object=self.user_subject)
+        ).delete()
+        UserFollowRequest.objects.filter(
+            Q(user_subject=self.user_subject, user_object=self.user_object) | \
+            Q(user_subject=self.user_object, user_object=self.user_subject)
+        ).delete()