SignalR 更改端口 - SelfHost

Question

我正在尝试使用远程请求更改我的服务器的端口。 当我这样做时，似乎一切正常，但是当我尝试连接时，我得到了一个异常。

如果我关闭（终止进程）然后使用新端口打开（启动进程）服务器，一切正常（客户端设法连接）。

服务器：

internal class Program
{
    private static IDisposable _webApp = null;
    static void Main(string[] args)
    {
        var uri = Start(8089);
        Stop();
        var uri = Start(8089);
        Console.WriteLine("Press enter to exit");
        Console.ReadLine();
    }

    private static string Start(int port)
    {
        var options = new StartOptions();
        var uri = string.Format("http://*:{0}/", port);
        options.Urls.Add(uri);
        options.Settings.Add(typeof(ITraceOutputFactory).FullName, typeof(NullTraceOutputFactory).AssemblyQualifiedName);// disable built-in owin tracing by using a null traceoutput
        var startup = new Startup
            {
                Restart = Restart
            };
        _webApp = WebApp.Start(options, startup.Configuration);
        Trace.Listeners.Remove("HostingTraceListener"); // remove the built-in owin listener
        Console.WriteLine("Server running at " + uri);
        return uri;
    }

    private static void Stop()
    {
        _webApp.Dispose();
    }

    private static string Restart(int port)
    {
        Stop();
        var uri = Start(port);
        return uri;
    }

    internal class NullTraceOutputFactory : ITraceOutputFactory
    {
        public TextWriter Create(string outputFile)
        {
            return StreamWriter.Null;
        }
    }
}

[HubName("Configuration")]
public class ConfigurationHub : Hub
{
    private Func<int, string> _restart;

    public ConfigurationHub(Func<int, string> restart)
    {
        _restart = restart;
    }

    public void ChangePort(int port)
    {
        Console.WriteLine("Port: " + port);
        _restart(port);
    }
}

internal class Startup
{
    public Func<int, string> Restart;

    public void Configuration(IAppBuilder app)
    {
        GlobalHost.DependencyResolver.Register(typeof(ConfigurationHub),
                () => new ConfigurationHub(Restart));
        app.UseCors(CorsOptions.AllowAll);
        //app.UseWelcomePage();
        var hubConfiguration = new HubConfiguration
        {
            EnableJSONP = true,
#if DEBUG
            EnableDetailedErrors = true
#endif
        };

        app.MapSignalR(hubConfiguration);
    }
}

客户：

public partial class Form1 : Form
{
    private IHubProxy _configurationProxy = null;
    private HubConnection _hubConnection;
    private const string CATEGORY = "ABCD";

    public Form1()
    {
        InitializeComponent();
        CreateProxy(8089);
        _hubConnection.Start().Wait();
    }

    private void btnChangePort_Click(object sender, EventArgs e)
    {
        var newPort = Int32.Parse(btnChangePort.Tag as string);
        _configurationProxy.Invoke("ChangePort", newPort);
        _hubConnection.Stop();
        _hubConnection.Dispose();
        _hubConnection = null;
        CreateProxy(newPort);
        _hubConnection.Start().Wait(); // <= Exception when clicking the button
    }

    private void CreateProxy(int newPort)
    {
        //var address = "127.0.0.1";
        var address = "192.168.0.100";
        var port = newPort;
        var config =
            new
                {
                    Name = "Configuration",
                    Pattern = "http://{0}:{1}",
                    Address = address,
                    Port = newPort,
                    QueryString = new Dictionary<string, string> { { "version", "1.0" } },
                    Methods = new[]
                        {
                            "notifyWrongVersion",
#if ERROR
                                "notifyConnected",
#endif
                            //"status",
                            "notifyByeBye"
                        },
                    MethodsCallbacks = new Action[]
                        {
                            () => Console.WriteLine("{0}: You are using the wrong version!", CATEGORY),
#if ERROR
                                    () => Trace.WriteLine("Connected to server! HOORAY!", Categories.CATEGORY_THIS),
#endif
                            () =>
                            Console.WriteLine("{0}: Bye bye from the server. Thank you for discnnecting.", CATEGORY)
                        },
                };

        var url = String.Format(config.Pattern, config.Address, config.Port);

        _hubConnection = new HubConnection(url);
        _hubConnection.TraceLevel = TraceLevels.All;
        _hubConnection.TraceWriter = Console.Out;
        _configurationProxy = _hubConnection.CreateHubProxy(config.Name);
    }
}

例外：

场景：
从客户端和服务器上的端口 8089 开始
按下客户端和服务器上的按钮更改为 8088
关闭客户端
用 8088 端口打开客户端。

客户端日志记录：

14:04:18.2450308 - null - ChangeState（断开连接，连接中） 14:04:18.7762877 - 708038b9-66b0-4cc2-95ac-de45411e453c - WS 连接到： WS：//192.168.250.9：8088 / signalr /连接clientProtocol = 1.4＆运输=的WebSockets＆connectionData = [{ “名称”： “配置”}]＆connectionToken = AQAAANCMnd8BFdERjHoAwE％2FCl％2BsBAAAAVaJK6bsSpkyFVlk1Ej463gAAAAACAAAAAAADZgAAwAAAABAAAAAcSxXM3loQOfD31c8mYLdqAAAAAASAAACgAAAAEAAAAISDmfaiIg％2BY％2FVt3bBI％2BZkAoAAAAd％2FngqVkiFGH55BN9NOW4nljYZzHBBwoTLxNwrj％2B31AiShmmgS6euMBQAAADjFYeiwsjjJ％ 2BRVX92GYdozAkKthw%3D%3D 14:04:23.8220044 - 708038b9-66b0-4cc2-95ac-de45411e453c - 自动：失败 使用传输 webSockets 连接。系统超时异常： 尝试连接时传输超时 14:04:23.8220044 - 708038b9-66b0-4cc2-95ac-de45411e453c - SSE：获取 http://192.168.250.9:8088/signalr/connect?clientProtocol=1.4&transport=serverSentEvents&connectionData=[ { “名称”： “配置”}]＆connectionToken = AQAAANCMnd8BFdERjHoAwE％2FCl％2BsBAAAAVaJK6bsSpkyFVlk1Ej463gAAAAACAAAAAAADZgAAwAAAABAAAAAcSxXM3loQOfD31c8mYLdqAAAAAASAAACgAAAAEAAAAISDmfaiIg％2BY％2FVt3bBI％2BZkAoAAAAd％2FngqVkiFGH55BN9NOW4nljYZzHBBwoTLxNwrj％2B31AiShmmgS6euMBQAAADjFYeiwsjjJ％2BRVX92GYdozAkKthw％3D％3D 14:04:23.9157549 - 708038b9-66b0-4cc2-95ac-de45411e453c - WS： OnClose() 14:04:23.9157549 - 708038b9-66b0-4cc2-95ac-de45411e453c - SSE：OnMessage（数据：初始化）14：04：28.8486354 - 708038b9-66b0-4cc2-95ac-de45411e453c - 自动：无法连接到 使用传输服务器SentEvents。 System.TimeoutException：传输 尝试连接时超时 14:04:28.8642594 - 708038b9-66b0-4cc2-95ac-de45411e453c - LP 连接： http://192.168.250.9:8088/signalr/connect?clientProtocol=1.4&transport=longPolling&connectionData=[ { “名称”： “配置”}]＆connectionToken = AQAAANCMnd8BFdERjHoAwE％2FCl％2BsBAAAAVaJK6bsSpkyFVlk1Ej463gAAAAACAAAAAAADZgAAwAAAABAAAAAcSxXM3loQOfD31c8mYLdqAAAAAASAAACgAAAAEAAAAISDmfaiIg％2BY％2FVt3bBI％2BZkAoAAAAd％2FngqVkiFGH55BN9NOW4nljYZzHBBwoTLxNwrj％2B31AiShmmgS6euMBQAAADjFYeiwsjjJ％2BRVX92GYdozAkKthw％3D％3D 14:04:33.8799023 - 708038b9-66b0-4cc2-95ac-de45411e453c - 自动：失败 连接到使用传输长轮询。系统超时异常： 尝试连接时传输超时 14:04:33.8799023 - 708038b9-66b0-4cc2-95ac-de45411e453c - 断开连接 14:04:33.8799023 - 708038b9-66b0-4cc2-95ac-de45411e453c - Transport.Dispose(708038b9-66b0-4cc2-95ac-de45411e453c) 14:04:33.8799023 - 708038b9-66b0-4cc2-95ac-de45411e453c - 关闭

在 3 次出现此错误后，我也得到了这个：

14:14:24.0350106 - null - OnError(System.TimeoutException: 客户端 自 2015 年 5 月 31 日 14:13:27 以来一直处于非活动状态，并且已超过 不活动超时 00:00:50。停止连接。）

Answer 1

我设法通过以下更改使其工作：

1) 让客户端和服务器在断开连接（客户端）或处置（服务器）之前有时间完成

服务器：

public void ChangePort(int port)
{
    Console.WriteLine("Received ChangePort request: " + port);
    Task.Delay(500).ContinueWith(_ => _restart(port));
}

客户：

_configurationProxy.Invoke("ChangePort", port)
    .ContinueWith(task =>
    {
        if (task.IsFaulted)
        {
            Console.WriteLine("ChangePort faulted: {0}", task.Exception.Flatten()); 
        }

        _hubConnection.Stop();
        _hubConnection.Dispose();
        _hubConnection = null;
    }).Wait();

2) 似乎在服务器处置期间处置了DependencyResolver 并且永远不会返回存在问题（请参阅此GitHub issue）。 This SO question 描述了您遇到的非常相似的问题。这是解决方案：

internal class Startup
    {
        public Func<int, string> Restart;

        public void Configuration(IAppBuilder app)
        {
            var resolver = new DefaultDependencyResolver();
            resolver.Register(typeof(ConfigurationHub), () => new ConfigurationHub(Restart));

            var hubConfiguration = new HubConfiguration
            {
                EnableJSONP = true,
                EnableDetailedErrors = true,
                Resolver = resolver
            };

            app.MapSignalR(hubConfiguration);
        }
    }

Answer 2

我们有类似的情况！而不是更改端口，我需要重新启动客户端或服务器端。

我使用计时器和全局标志“已连接”来达到目的。例如如果没有连接则每隔5秒尝试在客户端捕获连接功能，除非没有连接，否则第二次尝试通常可以，因为服务器重启速度不够快，第一次尝试通常失败！