static void Main(string[] args)
{
var system = ActorSystem.Create("system");
var mat = system.Materializer();
var inputPath = "Program.cs";
var outputPath = "Program.min.cs";
var files = File.ReadAllLines(inputPath);
var stream =
Source.From(files)
.Async()
.Select(line => Regex.Replace(line, @"\s|\t|\n|\r", ""))
.Async()
.Grouped(5)
//.To(Sink.ForEach<IEnumerable<string>>(lines => File.AppendAllLines(outputPath, lines)))
.ToMaterialized(Sink.AggregateAsync <IEnumerable <string>, int>(0, async(batchCount, lines) =>
{
var text = string.Join("", lines);
if (batchCount == 0)
{
await File.WriteAllTextAsync(outputPath, text);
}
else
{
await File.AppendAllTextAsync(outputPath, text);
}
return(++batchCount);
}), Keep.Right)
.Run(mat);
var totalBatchCount = stream.Result;
Console.WriteLine($"task completed with {totalBatchCount} batches.");
Console.ReadKey();
}