Fix race condition when updating competition tabs order.

thewca · Aug 3, 2019 · b6aaffa · b6aaffa
1 parent e5a9bcb
commit b6aaffa
Showing 1 changed file with 5 additions and 3 deletions.
diff --git a/WcaOnRails/app/models/competition_tab.rb b/WcaOnRails/app/models/competition_tab.rb
@@ -39,9 +39,11 @@ def reorder(direction)
     other_display_order = display_order + (direction.to_s == "up" ? -1 : 1)
     other_tab = competition.tabs.find_by(display_order: other_display_order)
     if other_tab
-      update_column :display_order, nil
+      ActiveRecord::Base.transaction do
-      other_tab.update_column :display_order, current_display_order
+        update_column :display_order, nil
-      update_column :display_order, other_display_order
+        other_tab.update_column :display_order, current_display_order
+        update_column :display_order, other_display_order
+      end
     end
   end
 end