public async Task <CreateCommandVariableResponse> Post(CreateCommandVariableRequest request)
        {
            if (!await batchRepository.DoesBatchExist(request.BatchId))
            {
                throw Err.BatchNotFound(request.BatchId);
            }

            var step = await stepRepository.Get(request.BatchId, request.StepName);

            if (step == null)
            {
                throw Err.StepNotFound(request.StepName);
            }

            var command = await commandRepository.Get(step.Id, request.CommandName);

            if (command == null)
            {
                throw Err.CommandNotFound(request.CommandName);
            }

            if (await commandRepository.DoesCommandVariableExist(request.BatchId, request.StepName, request.CommandName, request.VariableName))
            {
                throw Err.CommandVariableAlreadyExists(request.VariableName);
            }

            var commandVariable = request.ConvertTo <CommandVariable>();

            commandVariable.CommandId = command.Id;

            await commandRepository.CreateOrUpdateCommandVariable(commandVariable);

            return(new CreateCommandVariableResponse());
        }