关闭客户端时出现 SignalR Websocket 异常

Question

当启动和停止连接到基本自托管服务器的 SignalR 客户端时：

async public void Start(string url)
{
    _connection = new HubConnection(url);
    _proxy = _connection.CreateHubProxy("hubname");
    await _connection.Start().ContinueWith((task) => IsRunning = true);
}
public void Stop()
{
    _connection.Stop();
}

我在调用 "Stop" 方法（包括跟踪消息）时遇到以下异常：

SignalR.Transports.TransportHeartBeat Verbose: 0 : KeepAlive(c75fe282-a86d-406a-935b-5981b47bd472)
SignalR.Transports.TransportHeartBeat Information: 0 : Connection 1bdabc19-e0a7-4649-aabb-bade071ad6d0 is New.
SignalR.Transports.WebSocketTransport Information: 0 : Abort(1bdabc19-e0a7-4649-aabb-bade071ad6d0)
SignalR.Transports.TransportHeartBeat Information: 0 : Removing connection 1bdabc19-e0a7-4649-aabb-bade071ad6d0
SignalR.Transports.WebSocketTransport Information: 0 : End(1bdabc19-e0a7-4649-aabb-bade071ad6d0)
SignalR.Transports.WebSocketTransport Verbose: 0 : DrainWrites(1bdabc19-e0a7-4649-aabb-bade071ad6d0)
SignalR.Transports.WebSocketTransport Information: 0 : CloseSocket(1bdabc19-e0a7-4649-aabb-bade071ad6d0)
App.vshost.exe Error: 0 : Error while closing the websocket: System.Net.WebSockets.WebSocketException (0x80004005): An internal WebSocket error occurred. Please see the innerException, if present, for more details.  ---> System.Net.Sockets.SocketException (0x80004005): An existing connection was forcibly closed by the remote host
   at System.Net.WebSockets.WebSocketConnectionStream.WebSocketConnection.WriteAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
   at System.Net.WebSockets.WebSocketConnectionStream.<WriteAsync>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Net.WebSockets.WebSocketBase.<SendFrameAsync>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Net.WebSockets.WebSocketBase.WebSocketOperation.<Process>d__47.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Net.WebSockets.WebSocketBase.<CloseOutputAsyncCore>d__17.MoveNext()
   at System.Net.WebSockets.WebSocketBase.ThrowIfConvertibleException(String methodName, Exception exception, CancellationToken cancellationToken, Boolean aborted)
   at System.Net.WebSockets.WebSocketBase.<CloseOutputAsyncCore>d__17.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNet.SignalR.WebSockets.WebSocketHandler.<<CloseAsync>b__6>d__8.MoveNext()
App.vshost.exe Error: 0 : Error while closing the websocket: System.Net.WebSockets.WebSocketException (0x80004005): An internal WebSocket error occurred. Please see the innerException, if present, for more details.  ---> System.Net.Sockets.SocketException (0x80004005): An existing connection was forcibly closed by the remote host
   at System.Net.WebSockets.WebSocketConnectionStream.WebSocketConnection.WriteAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
   at System.Net.WebSockets.WebSocketConnectionStream.<WriteAsync>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Net.WebSockets.WebSocketBase.<SendFrameAsync>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Net.WebSockets.WebSocketBase.WebSocketOperation.<Process>d__47.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Net.WebSockets.WebSocketBase.<CloseOutputAsyncCore>d__17.MoveNext()
   at System.Net.WebSockets.WebSocketBase.ThrowIfConvertibleException(String methodName, Exception exception, CancellationToken cancellationToken, Boolean aborted)
   at System.Net.WebSockets.WebSocketBase.<CloseOutputAsyncCore>d__17.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNet.SignalR.WebSockets.WebSocketHandler.<<CloseAsync>b__6>d__8.MoveNext()
SignalR.Transports.WebSocketTransport Information: 0 : CompleteRequest (1bdabc19-e0a7-4649-aabb-bade071ad6d0)
SignalR.Transports.TransportHeartBeat Verbose: 0 : KeepAlive(c75fe282-a86d-406a-935b-5981b47bd472)
SignalR.Transports.TransportHeartBeat Verbose: 0 : KeepAlive(c75fe282-a86d-406a-935b-5981b47bd472)

设置本身似乎工作正常，设备可以连接、发送、接收和断开连接。但是随着每次断开连接，我都会遇到上面的丑陋异常。知道问题可能是什么吗？我正在使用 SignalR 2.2.0 和 Owin 1.2.2。

Answer 1

如果我没理解错，你想在客户端断开时停止广播消息。所以我的方法是在 SignalR 中使用连接生命周期事件。这是官方页面：SignalRLifeTimeEvents

public override System.Threading.Tasks.Task OnDisconnected()
{
    //-- When any client will close the browser or page this event will fire

    return base.OnDisconnected();
}

Answer 2

看起来像 known issue，可能会在 v3 中修复。

Answer 3

好的伙计们，我知道它很蹩脚。我试图在主窗口关闭时关闭 signalr 客户端，但我遇到了很多我无法捕获的异常，并且我的进程挂起了。所以我决定在表单关闭时终止主进程。

private void OnClose(object sender, CancelEventArgs e){
        try
        {
            var process = Process.GetCurrentProcess();
            process.Kill();
            //HubConnection.Stop();
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex);
        }

}

Answer 4

尝试为关闭方法提供一个 TimeSpan，让它有时间实际关闭，同时等待任何可能正在进行的异步进程：

public void Stop()
{
    _connection.Stop(new TimeSpan(1000));
}

这对我有用。

Answer 5

我用

解决了这个问题

connection.Reconnecting += connection.Stop;

因为我发现连接状态一直是reconnecting

关闭客户端时出现 SignalR Websocket 异常

SignalR Websocket Exception when closing client

c#

sockets

signalr.client

owin

signalr-2