コード例 #1
0
        /// <summary>
        /// This generate customer billing through "Producer Consumer" pattern, with parallelization.
        /// The maximum number of threads is equivalent to processors count (default), but can be customized in appsettings.json
        /// The amount of days to calculate the due date from today is also customized.
        /// </summary>
        protected override async Task ExecuteAsync(CancellationToken stoppingToken)
        {
            var blockingCollection = new BlockingCollection <string>(_customerBillingGeneratorSettings.BoundedCapacityForBlockingCollection.Value);

            Action <string> billCalculatingWork = cpf =>
            {
                double value = Double.Parse($"{cpf.Substring(0,2)}{cpf.Substring(cpf.Length-2, 2)}");
                _billingApiService.Add(new Bill()
                {
                    DueDate  = DateTime.Now.AddDays(_customerBillingGeneratorSettings.AmountOfDaysToDueDate.Value),
                    PersonId = cpf, Value = value
                });
            };

            _ = Task.Run(async() =>
            {
                IEnumerable <string> customerIds = await _customerApiService.GetAllIdsAsync();

                foreach (string id in customerIds.ToList())
                {
                    blockingCollection.Add(id);
                }

                blockingCollection.CompleteAdding();
            });

            blockingCollection
            .GetConsumingEnumerable()
            .AsParallel()
            .WithDegreeOfParallelism(_customerBillingGeneratorSettings.MaxNumberOfConcurrentTasks.Value)
            .WithMergeOptions(ParallelMergeOptions.NotBuffered)
            .ForAll(billCalculatingWork);

            await Task.CompletedTask;
        }