static async Task Main(string[] args)
{
var listener = new TcpListener(IPAddress.Loopback, port);
var terminator = new Terminator();
var cts = new CancellationTokenSource();
var ct = cts.Token;
Console.CancelKeyPress += (obj, eargs) =>
{
Log("CancelKeyPress, stopping server");
cts.Cancel();
listener.Stop();
eargs.Cancel = true;
};
listener.Start();
Log($"Listening on {port}");
using (ct.Register(() => { listener.Stop(); }))
{
try
{
while (!ct.IsCancellationRequested)
{
Log("Accepting new TCP client");
var client = await listener.AcceptTcpClientAsync();
var id = counter++;
Log($"connection accepted with id '{id}'");
Handle(id, client, ct, terminator);
}
}
catch (Exception e)
{
// await AcceptTcpClientAsync will end up with an exception
Log($"Exception '{e.Message}' received");
}
Log("waiting shutdown");
await terminator.Shutdown();
}
}
private static async void Handle(
int id,
TcpClient client,
CancellationToken cancellationToken,
Terminator terminator)
{
using (terminator.Enter())
{
try
{
using (client)
{
var stream = client.GetStream();
var reader = new JsonTextReader(new StreamReader(stream))
{
// To support reading multiple top-level objects
SupportMultipleContent = true
};
var writer = new JsonTextWriter(new StreamWriter(stream));
while (true)
{
try
{
// to consume any bytes until start of object ('{')
do
{
await reader.ReadAsync(cancellationToken);
Log($"advanced to {reader.TokenType}");
} while (reader.TokenType != JsonToken.StartObject &&
reader.TokenType != JsonToken.None);
if (reader.TokenType == JsonToken.None)
{
Log($"[{id}] reached end of input stream, ending.");
return;
}
Log("Reading object");
var json = await JObject.LoadAsync(reader, cancellationToken);
Log($"Object read, {cancellationToken.IsCancellationRequested}");
var request = json.ToObject <Request>();
Response response = null;
switch (request.Method)
{
case "ECHO":
response = Echo(request, json);
break;
case "DELAY":
response = await Delay(request);
break;
default:
response = new Response()
{
Status = 405
};
break;
}
serializer.Serialize(writer, response);
await writer.FlushAsync(cancellationToken);
}
catch (JsonReaderException e)
{
Log($"[{id}] Error reading JSON: {e.Message}, ending");
var response = new Response
{
Status = 400,
};
serializer.Serialize(writer, response);
await writer.FlushAsync(cancellationToken);
// close the connection because an error may not be recoverable by the reader
return;
}
catch (Exception e)
{
Log($"[{id}] Exception: {e.Message}, ending");
return;
}
}
}
}
finally
{
Log($"Ended connection {id}");
}
}
}
public TerminatorDisposable(Terminator terminator)
{
this.terminator = terminator;
}
