Avoid plucking Todo ids and use sub-queries instead

TodoService should not call `.select(&:id)` on todos, because this is
bad performance. So instead use sub-queries, which will result in a
single SQL query to the database.

https://docs.gitlab.com/ee/development/sql.html#plucking-ids

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/api/todos.rb b/lib/api/todos.rb
index d1f7e364029..55191169dd4 100644
--- a/lib/api/todos.rb
+++ b/lib/api/todos.rb
@@ -59,10 +59,10 @@ module API
         requires :id, type: Integer, desc: 'The ID of the todo being marked as done'
       end
       post ':id/mark_as_done' do
-        todo = current_user.todos.find(params[:id])
-        TodoService.new.mark_todos_as_done([todo], current_user)
+        TodoService.new.mark_todos_as_done_by_ids(params[:id], current_user)
+        todo = Todo.find(params[:id])
 
-        present todo.reload, with: Entities::Todo, current_user: current_user
+        present todo, with: Entities::Todo, current_user: current_user
       end
 
       desc 'Mark all todos as done'