inabox/InABox.Client.RPC/Transports/Socket/RPCClientSocketTransport.cs

using System;
using System.Threading.Tasks;
using InABox.Clients;
using InABox.Core;
using WebSocketSharp;
using ErrorEventArgs = WebSocketSharp.ErrorEventArgs;

namespace InABox.Rpc
{
    public class RpcClientSocketTransport : RpcClientTransport, IDisposable
    {
        private WebSocket _socket;
        private string _url;
        public RpcClientSocketTransport(string url)
        {
            _url = url;
        }
        
        private void Socket_OnOpen(object? sender, EventArgs e)
        {
            DoOpen();
        }
        
        private void Socket_OnMessage(object? sender, MessageEventArgs e)
        {
            RpcMessage? message = null;
            if (e.IsBinary && (e.RawData != null))
                message = Serialization.ReadBinary<RpcMessage>(e.RawData, BinarySerializationSettings.Latest);
            else if (e.IsText && !string.IsNullOrWhiteSpace(e.Data))
                message = Serialization.Deserialize<RpcMessage>(e.Data);
     
            Accept(message);
        }

        private void Socket_OnClose(object? sender, CloseEventArgs e)
        {
            DoClose(RpcTransportCloseEventType.Closed);
        }

        private void Socket_OnError(object? sender, ErrorEventArgs e)
        {
            DoException(e.Exception);
        }


        private WebSocket CreateSocket(bool secure)
        {
            var socket = new WebSocket($"{(secure ? "wss" : "ws")}://{_url}");            
            
            // Time to wait before disconnect - the default meant that the client disconnected during debugging, since the ping would fail
            socket.WaitTime = TimeSpan.FromSeconds(5);
            socket.OnOpen -= Socket_OnOpen;
            socket.OnError -= Socket_OnError;
            socket.OnClose -= Socket_OnClose;
            socket.OnMessage -= Socket_OnMessage;
            socket.Connect();
            if (socket.ReadyState == WebSocketState.Open)
            {
                DoOpen();

                socket.OnOpen += Socket_OnOpen;
                socket.OnError += Socket_OnError;
                socket.OnClose += Socket_OnClose;
                socket.OnMessage += Socket_OnMessage;

                return socket;
            }

            return null;
        }
        
        public override void Connect()
        {
            var findsocket = new Task<WebSocket>[]
            {
                Task<WebSocket>.Run(() => CreateSocket(true)),
                Task<WebSocket>.Run(() => CreateSocket(false))
            } ;
            var index = Task.WaitAny(findsocket);
            
            _socket = findsocket[index].Result;
        }

        public override bool IsConnected() => _socket?.ReadyState == WebSocketState.Open;
        public override bool IsSecure() => _socket?.IsSecure == true;
        
        public override void Disconnect()
        {
            _socket.Close(CloseStatusCode.Normal);
        }

        public override void Send(RpcMessage message)
        {
            var buffer = Serialization.WriteBinary(message, BinarySerializationSettings.Latest);
            _socket.Send(buffer);
        }

        protected override RpcClientTransport Clone() => new RpcClientSocketTransport(_url);

        public void Dispose()
        {
            if (IsConnected())
                Disconnect();
        }
    }
}