New

This is a fork of EngineIOSharp:master with additional support for socket connection pre-processing!

using (EngineIOServer server = new EngineIOServer(new EngineIOServerOption(1009, AllowEIO3: true, VerificationTimeout: 1001)))
{
    Console.WriteLine("Listening on " + server.Option.Port);
    server.OnConnecting((obj) =>
    {
        var token = obj.Item1["token2"];
        if (string.IsNullOrWhiteSpace(token))
        {
            Console.WriteLine($"{DateTime.Now:HH:mm:ss.fff} The authentication fails and the connection is denied");
        }
        server.VerificationResult.TryAdd(obj.Item2, string.IsNullOrWhiteSpace(token));
    });
    server.OnConnection((socket) =>
    {
        Console.WriteLine($"{DateTime.Now:HH:mm:ss.fff} Client connected!");
    });

    server.Start();
}

Added

1.EngineIOSharp/Server/EngineIOServer.Exceptions.cs

public static readonly EngineIOException CONNECTIONREFUSED = new EngineIOException("ConnectionRefused");//401/403
private static readonly EngineIOException[] VALUES = new EngineIOException[] { CONNECTIONREFUSED }

2.EngineIOSharp/Server/EngineIOServer.Event.cs

public EngineIOServer OnConnecting(Action<Tuple<System.Collections.Specialized.NameValueCollection, string>> Callback)
{
	return On(Event.CONNECTING, (Client) => Callback(Client as Tuple<System.Collections.Specialized.NameValueCollection, string>));
}
public static class Event
{
	public static readonly string CONNECTING = "connecting";
}

3.EngineIOSharp/Common/Static/EngineIOHttpManager.cs

public static void SendErrorMessage(HttpListenerRequest Request, HttpListenerResponse Response, EngineIOException Exception)
{
    using (Response)
    {
        ......
        if (EngineIOServer.Exceptions.Contains(Exception))
        {
            ......
            Response.StatusCode = 400;
            Response.Headers["ServerResponse"] = Message;
            Response.StatusCode = Exception == EngineIOServer.Exceptions.CONNECTIONREFUSED ? 401 : 400;
        }
        else
        {
            ......
        }

        ......
    }
}

4.EngineIOSharp/Server/EngineIOServerOption.cs

public ulong VerificationTimeout { get; private set; }
public EngineIOServerOption(ulong VerificationTimeout = 1000)
{
	this.VerificationTimeout = VerificationTimeout;
}

5.EngineIOSharp/Server/EngineIOServer.cs

/// <summary>
/// Verification result: If no entry is made within 1000ms, it is regarded as passed
/// </summary>
public readonly ConcurrentDictionary<string, bool> VerificationResult = new ConcurrentDictionary<string, bool>();
private EngineIOException Verify(NameValueCollection QueryString, NameValueCollection Headers, EngineIOTransportType ExpectedTransportType)
{
    ......
    else if (EngineIOHttpManager.GetTransport(QueryString).Equals(ExpectedTransportType.ToString()))
    {
        ......
        if (IsPolling || IsWebSocket)
        {
            if (EngineIOHttpManager.IsValidHeader(EngineIOHttpManager.GetOrigin(Headers)))
            {
                Exception = null;
                #region connection verification
				if (string.IsNullOrWhiteSpace(EngineIOHttpManager.GetSID(QueryString)))
				{
					var abortId = $"{QueryString}&k={DateTime.Now.Ticks}";
					Emit(Event.CONNECTING, new Tuple<NameValueCollection, string>(Headers, abortId));

#if NET45_OR_GREATER
				//var task = System.Threading.Tasks.Task.Run(() => { while (!VerificationResult.ContainsKey(abortId)) { continue; } });
				//System.Threading.Tasks.Task.WaitAny(new System.Threading.Tasks.Task[] { task }, TimeSpan.FromMilliseconds(Option.VerificationTimeout));

				var cts = new System.Threading.CancellationTokenSource(TimeSpan.FromMilliseconds(Option.VerificationTimeout));
				while (!VerificationResult.ContainsKey(abortId) && !cts.IsCancellationRequested) { continue; }
#else
					var cts = new System.Threading.CancellationTokenSource();
					var waitTimer = new System.Timers.Timer(Option.VerificationTimeout) { AutoReset = false };
					waitTimer.Elapsed += (aa, bb) => cts.Cancel();
					waitTimer.Start();
					while (!VerificationResult.ContainsKey(abortId) && !cts.IsCancellationRequested) { continue; }
#endif
					if (VerificationResult.TryGetValue(abortId, out var result))
					{
						VerificationResult.TryRemove(abortId, out _);
						if (result) Exception = Exceptions.CONNECTIONREFUSED;
					}
				}
				#endregion
            }
            else
            {
                Exception = Exceptions.BAD_REQUEST;
            }
        }
    }

    return Exception;
}

EngineIOSharp

EngineIOSharp is a Engine.IO Protocol revision 4 client and server library based on WebSocket or Long-Polling transport. It depends on WebSocketSharp to use WebSocket transport. Long-Polling transport is implemented by itself.

Installation

• Nuget gallery

• Command Install-Package EngineIOIOSharp2 in nuget package manager console.

Usage

Client

Namespace

using EngineIOSharp.Client;
using EngineIOSharp.Common.Enum;

Constructor

EngineIOClient client = new EngineIOClient(new EngineIOClientOption(EngineIOScheme.http, "localhost", 1009)));

EngineIOClientOption

• Essential Parameters

  • Scheme : Scheme to connect to. It can be EngineIOScheme.http or EngineIOScheme.https. Internally, it supports ws and wss.

  • Host : Host to connect to.

  • Port : Port to connect to.

• Optional Parameters

  • PolicyPort : Port the policy server listens on. Defaults to 843.

  • Path : Path to connect to. Defaults to "/engine.io".

  • Query : Parameters that will be passed for each request to the server. Defaults to null.

  • Upgrade : Whether the client should try to upgrade the transport. Defaults to true.

  • RemeberUpgrade : Whether the client should bypass normal upgrade process when previous websocket connection is succeeded. Defaults to false.

  • ForceBase64 : Forces base 64 encoding for transport. Defaults to false.

  • WithCredentials : Whether to include credentials such as cookies, authorization headers, TLS client certificates, etc. with polling requests. Defaults to false.

  • TimestampRequests : Whether to add the timestamp with each transport request. Polling requests are always stamped. Defaults to null.

  • TimestampParam : Timestamp parameter. Defaults to "t".

  • Polling : Whether to include polling transport. Defaults to true.

  • PollingTimeout : Timeout for polling requests in milliseconds. Defaults to 0, which waits indefinitely.

  • WebSocket : Whether to include websocket transport. Defaults to true.

  • WebSocketSubprotocols : List of websocket subprotocols. Defaults to null.

  • ExtraHeaders : Headers that will be passed for each request to the server. Defaults to null.

  • ClientCertificates : The collection of security certificates that are associated with each request. Defaults to null.

  • ClientCertificateSelectionCallback : Callback used to select the certificate to supply to the server. Defaults to null.

  • ServerCertificateValidationCallback : Callback method to validate the server certificate. Defaults to null and server certificate will be always validated.

Connect

client.Connect();

Disconnect

client.Close();

or

client.Dispose();

Since EngineIOClient implements IDisposable interface, it will be automatically disconnected when EngineIOClient.Dispose is called.

Handlers

For convenient usage, it is implemented to can be used as Javascript style.

client.OnOpen(() =>
{
  Console.WriteLine("Conencted!");
});

client.OnMessage((Packet) =>
{
  Console.WriteLine("Server : " + Packet.Data);
});

client.OnClose((Exception Description) =>
{
  Console.WriteLine("Disconnected!");
  
  if (Description != null)
  {
    Console.WriteLine(Description);
  }
});

client.On(EngineIOClient.Event.FLUSH, () =>
{
  Console.WriteLine("Flushed!");
});

EngineIOClient.Event

public static class Event
{
  public static readonly string OPEN = "open";
  public static readonly string HANDSHAKE = "handshake";

  public static readonly string ERROR = "error";
  public static readonly string CLOSE = "close";

  public static readonly string PACKET = "packet";
  public static readonly string MESSAGE = "message";

  public static readonly string PACKET_CREATE = "packetCreate";
  public static readonly string FLUSH = "flush";
  public static readonly string DRAIN = "drain";

  public static readonly string UPGRADE = "upgrade";
  public static readonly string UPGRADING = "upgrading";
  public static readonly string UPGRADE_ERROR = "upgradeError";
}

These are the common basic Engine.IO events.

Send

client.Send("This is string value.");
client.Send("String value with callback.", () => Console.WriteLine("Flushed!"));

client.send(new byte[] { 1, 2, 3, 4, 5 });
client.send(new byte[] { 6, 7, 8, 9, 0 }, () => Console.WriteLine("Bytes flushed!"));

Server

Namespace

using EngineIOSharp.Server;

Constructor

EngineIOServer server = new EngineIOServer(new EngineIOServerOption(1009));

EngineIOServerOption

• Essential Parameters

  • Port : Port to listen.

• Optional Parameters

  • Path : Path to listen. Defaults to "/engine.io".

  • Secure : Whether to secure connections. Defatuls to false.

  • PingTimeout : How many ms without a pong packet to consider the connection closed. Defatuls to 5000.

  • PingInterval : How many ms before sending a new ping packet. Defatuls to 25000.

  • UpgradeTimeout : How many ms before an uncompleted transport upgrade is cancelled. Defatuls to 10000.

  • Polling : Whether to accept polling transport. Defatuls to true.

  • WebSocket : Whether to accept websocket transport. Defatuls to true.

  • AllowUpgrade : Whether to allow transport upgrade. Defatuls to true.

  • SetCookie : Whether to use cookie. Defatuls to true.

  • SIDCookieName : Name of sid cookie. Defatuls to "io".

  • Cookies : Configuration of the cookie that contains the client sid to send as part of handshake response headers. This cookie might be used for sticky-session. Defatuls to null.

  • AllowHttpRequest : A function that receives a given handshake or upgrade http request as its first parameter, and can decide whether to continue or not. Defatuls to null.

  • AllowWebSocket : A function that receives a given handshake or upgrade websocket connection as its first parameter, and can decide whether to continue or not. Defatuls to null.

  • InitialData : An optional packet which will be concatenated to the handshake packet emitted by Engine.IO. Defatuls to null.

  • ServerCertificate : The certificate used to authenticate the server. Defatuls to null.

  • ClientCertificateValidationCallback : Callback used to validate the certificate supplied by the client. Defatuls to null and client certificate will be always validated.

Start

server.Start();

Stop

server.Stop();

or

server.Dispose();

Since EngineIOServer implements IDisposable interface, it will be automatically stoped when EngineIOServer.Dispose is called.

Connection

For convenient usage, it is implemented to can be used as Javascript style.

server.OnConnection((EngineIOSocket socket) =>
{
  Console.WriteLine("Client connected!");

  socket.OnMessage((Packet) =>
  {
    Console.WriteLine(Packet.Data);

    if (Packet.IsText)
    {
      socket.Send(Packet.Data);
    }
    else
    {
      socket.Send(Packet.RawData);
    }
  });

  socket.OnClose(() =>
  {
    Console.WriteLine("Client disconnected!");
  });

  socket.Send("Hello client!");
  socket.Send(new byte[] { 0, 1, 2, 3, 4, 5, 6 });
});

EngineIOSocket

• EngineIOSocket is a type of parameter in EngineIOServer.OnConnection event callback. It can be used similarly as EngineIOClient.

Disconnect

socket.Close();

or

socket.Dispose();

Since EngineIOSocket implements IDisposable interface, it will be automatically disconnected when EngineIOSocket.Dispose is called.

Handlers

For convenient usage, it is implemented to can be used as Javascript style.

socket.OnMessage((Packet) =>
{
  Console.WriteLine("Server : " + Packet.Data);
});

socket.OnClose((string Messsage, Exception Description) =>
{
  Console.WriteLine("Disconnected!");
  
  if (Message != null) 
  {
    Console.WriteLine(Message);
  }
  
  if (Description != null)
  {
    Console.WriteLine(Description);
  }
});

socket.On(EngineIOSocket.Event.FLUSH, () =>
{
  Console.WriteLine("Flushed!");
});

• There is no EngineIOSocket.OnOpen event since it is already opened when EngineIOServer.OnConnection event callback is called.

EngineIOSocket.Event

public static class Event
{
  public static readonly string OPEN = "open";
  public static readonly string HEARTBEAT = "heartbeat";

  public static readonly string ERROR = "error";
  public static readonly string CLOSE = "close";

  public static readonly string PACKET = "packet";
  public static readonly string MESSAGE = "message";

  public static readonly string PACKET_CREATE = "packetCreate";
  public static readonly string FLUSH = "flush";
  public static readonly string DRAIN = "drain";

  public static readonly string UPGRADE = "upgrade";
  public static readonly string UPGRADING = "upgrading";
  public static readonly string UPGRADE_ERROR = "upgradeError";
}

Send

socket.Send("This is string value.");
socket.Send("String value with callback.", () => Console.WriteLine("Flushed!"));

socket.send(new byte[] { 1, 2, 3, 4, 5 });
socket.send(new byte[] { 6, 7, 8, 9, 0 }, () => Console.WriteLine("Bytes flushed!"));

Broadcast

server.Braodcast("This is string value.");
server.Braodcast("String value with callback.", () => Console.WriteLine("Braodcasted!"));

server.Braodcast(new byte[] { 1, 2, 3, 4, 5 });
server.Braodcast(new byte[] { 6, 7, 8, 9, 0 }, () => Console.WriteLine("Bytes braodcasted!"));

Maintenance

Welcome to report issue or create pull request. I will check it happily.

Dependencies

• WebSocketSharp.CustomHeaders.CustomHttpServer v1.0.2.3
• SimpleThreadMonitor v1.0.2.1
• Newtonsoft.Json v9.0.1
• EmitterSharp v1.1.1.1

License

EngineIOSharp is under The MIT License.