public void Pong(Guid pingId, long clientTimeSent)
{
//simulate up latency here
//System.Threading.Thread.Sleep(2000);
var serverTimeReceived = DateTime.UtcNow;
var ping = Pings[pingId];
var clientPing = TimeSyncMessage.NewFrom(ping);
clientPing.ConnectionId = Context.ConnectionId;
clientPing.ClientTimeSent = JavaScriptDateConverter.Convert(clientTimeSent);
clientPing.ServerTimeReceived = serverTimeReceived;
Pongs.AddOrUpdate(clientPing.ConnectionId, c => clientPing, (c, old) =>
{
if (old.Roundtrip > clientPing.Roundtrip)
{
//this was more accurate...use it
return(clientPing);
}
else
{
return(old);
}
});
ShowPings();
}
//Usage
public string SendCommand(long clientTimeSent, string message = "General Command")
{
//Random r = new Random();
//var upArtificialLatency = r.Next(500, 1500);
//var downArtificialLatency = r.Next(0, 500);
//simulate up latency here
//System.Threading.Thread.Sleep(upArtificialLatency);
var serverReceiveDateTime = DateTime.UtcNow;
var clientDateTime = JavaScriptDateConverter.Convert(clientTimeSent);
Pongs.TryGetValue(Context.ConnectionId, out TimeSyncMessage senderTimeSync);
var sendTimeFromServerPerspective = clientDateTime.Subtract(senderTimeSync.ClientOffsetTimespan);
TimeSpan possibleUpLatency = serverReceiveDateTime - sendTimeFromServerPerspective;
if (possibleUpLatency.TotalMilliseconds >= 500)
{
//fail command
//return $"Command rejected: already {possibleUpLatency.TotalMilliseconds}ms old.";
message += $"(passed server threshold. saw {possibleUpLatency.TotalMilliseconds}ms)";
}
ClientIds.Keys.Where(id => id != Context.ConnectionId).ToList().ForEach(id =>
{
//get
if (!Pongs.TryGetValue(id, out TimeSyncMessage receiverTimeSync))
{
return;
}
var sendTimeFromReceiverPerspective = sendTimeFromServerPerspective.Add(receiverTimeSync.ClientOffsetTimespan);
var wrappedMessage = new
{
sendTimeFromSendersPerspective = clientDateTime,
sendTimeFromServerPerspective,
sendTimeFromReceiverPerspective,
sendTime = JavaScriptDateConverter.Convert(sendTimeFromReceiverPerspective),
message,
// upArtificialLatency,
//downArtificialLatency,
//totalArtificialLatency = upArtificialLatency + downArtificialLatency
};
//simulate down latency here
//System.Threading.Thread.Sleep(downArtificialLatency);
Clients.Client(id).receiveCommand(wrappedMessage);
});
return("");
}