public async Task <IEnumerable <CheckPointDto> > GetCheckPointsofParentTask(int parentTaskId) { if (!await taskRepository.isTaskExist(parentTaskId)) { throw new Exception("task not exist"); } var Checkpoints = await checkpointRepository.GetAllCheckpointsByParentTaskId(parentTaskId); return(Checkpoints.Select(c => mapper.Map <CheckPointDto>(c)).ToList()); }