public async Task Handle(RemoveDayAssignMembersEvent message)
 {
     await Update(message.SourceId,
                  Builders <DayAssign> .Update.PullAll(f => f.UserIdList, message.UserIdList));
 }
 private void Apply(RemoveDayAssignMembersEvent e)
 {
     UserIdList = e.UserIdList;
 }