Delete confidential issue todos for guests

Fix leaking information of confidential issues on TODOs
when user is downgraded to guest access.

3 files changed, 16 insertions, 7 deletions

diff --git a/app/services/members/base_service.rb b/app/services/members/base_service.rb
index d734571f835..e78affff797 100644
--- a/app/services/members/base_service.rb
+++ b/app/services/members/base_service.rb
@@ -47,5 +47,11 @@ module Members
         raise "Unknown action '#{action}' on #{member}!"
       end
     end
+
+    def enqueue_delete_todos(member)
+      type = member.is_a?(GroupMember) ? 'Group' : 'Project'
+      # don't enqueue immediately to prevent todos removal in case of a mistake
+      TodosDestroyer::EntityLeaveWorker.perform_in(Todo::WAIT_FOR_DELETE, member.user_id, member.source_id, type)
+    end
   end
 end
diff --git a/app/services/members/destroy_service.rb b/app/services/members/destroy_service.rb
index c186a5971dc..ae0c644e6c0 100644
--- a/app/services/members/destroy_service.rb
+++ b/app/services/members/destroy_service.rb
@@ -15,7 +15,7 @@ module Members
         notification_service.decline_access_request(member)
       end
 
-      enqeue_delete_todos(member)
+      enqueue_delete_todos(member)
 
       after_execute(member: member)
 
@@ -24,12 +24,6 @@ module Members
 
     private
 
-    def enqeue_delete_todos(member)
-      type = member.is_a?(GroupMember) ? 'Group' : 'Project'
-      # don't enqueue immediately to prevent todos removal in case of a mistake
-      TodosDestroyer::EntityLeaveWorker.perform_in(1.hour, member.user_id, member.source_id, type)
-    end
-
     def can_destroy_member?(member)
       can?(current_user, destroy_member_permission(member), member)
     end
diff --git a/app/services/members/update_service.rb b/app/services/members/update_service.rb
index 1f5618dae53..ff8d5c1d8c9 100644
--- a/app/services/members/update_service.rb
+++ b/app/services/members/update_service.rb
@@ -10,9 +10,18 @@ module Members
 
       if member.update(params)
         after_execute(action: permission, old_access_level: old_access_level, member: member)
+
+        # Deletes only confidential issues todos for guests
+        enqueue_delete_todos(member) if downgrading_to_guest?
       end
 
       member
     end
+
+    private
+
+    def downgrading_to_guest?
+      params[:access_level] == Gitlab::Access::GUEST
+    end
   end
 end