Merge branch 'bugfix/delete-activity-audience' into 'develop'

expand the audience of delete activities to all recipients of the deleted object

Closes #682

See merge request !891

lib/pleroma/web/activity_pub/activity_pub.ex

@@ -309,12 +309,13 @@ def unfollow(follower, followed, activity_id \\ nil, local \\ true) do
 
   def delete(%Object{data: %{"id" => id, "actor" => actor}} = object, local \\ true) do
     user = User.get_cached_by_ap_id(actor)
+    to = object.data["to"] || [] ++ object.data["cc"] || []
 
     data = %{
       "type" => "Delete",
       "actor" => actor,
       "object" => id,
-      "to" => [user.follower_address, "https://www.w3.org/ns/activitystreams#Public"]
+      "to" => to
     }
 
     with {:ok, _} <- Object.delete(object),

test/web/activity_pub/activity_pub_test.exs

@@ -691,6 +691,27 @@ test "decrements user note count only for public activities" do
       user = Repo.get(User, user.id)
       assert user.info.note_count == 10
     end
+
+    test "it creates a delete activity and checks that it is also sent to users mentioned by the deleted object" do
+      user = insert(:user)
+      note = insert(:note_activity)
+
+      {:ok, object} =
+        Object.get_by_ap_id(note.data["object"]["id"])
+        |> Object.change(%{
+          data: %{
+            "actor" => note.data["object"]["actor"],
+            "id" => note.data["object"]["id"],
+            "to" => [user.ap_id],
+            "type" => "Note"
+          }
+        })
+        |> Object.update_and_set_cache()
+
+      {:ok, delete} = ActivityPub.delete(object)
+
+      assert user.ap_id in delete.data["to"]
+    end
   end
 
   describe "timeline post-processing" do