在WCF服务

Question

您好我有一个WCF服务，它接收来自Web前端的请求。然后，服务连接到SignalR集线器并向订户发送消息。这一切都适用于单个请求。但是当我用多个请求加载服务时（通常不超过8个）。 signalR连接似乎丢失，Web客户端无法连接到Hub。一段时间后，这最终会释放，客户再次开始连接。

我的假设是它与WCF服务中的HubConnection的生命周期有关。我尝试了以下方法来解决这个问题，但似乎都没有。我确定我错过了一些非常明显的东西。

方法1 - 创建连接，不要处置并让它超出GC的范围。

 // Establish connection to the SignalRHub.
        var hubConnection = new HubConnection(this.signalRHost + "/signalr", useDefaultUrl: false);
        hubConnection.Credentials = CredentialCache.DefaultNetworkCredentials;
        IHubProxy hubProxy = hubConnection.CreateHubProxy(this.dataCollectionServiceHubName);

        // Start connection to signalR hub.
        hubConnection.Start().ContinueWith((result) =>
        {
            hubProxy.Invoke("SendAll", message);
        });

方法2 - 在发送消息后呼叫停止。

// Establish connection to the SignalRHub.
        var hubConnection = new HubConnection(this.signalRHost + "/signalr", useDefaultUrl: false);
        hubConnection.Credentials = CredentialCache.DefaultNetworkCredentials;
        IHubProxy hubProxy = hubConnection.CreateHubProxy(this.dataCollectionServiceHubName);

        // Start connection to signalR hub.
        hubConnection.Start().ContinueWith((result) =>
            {                    
                hubProxy.Invoke("SendAll", message).ContinueWith((r) => { hubConnection.Stop(); });
            });

    }

方法3 - 使用块中的crate连接，以便在发送后调用Dispose。

 using (var hubConnection = this.connectionFactory.Create())
        {
            // Establish connection to the SignalRHub.
            IHubProxy hubProxy = hubConnection.CreateHubProxy(this.dataCollectionServiceHubName);

            // Start connection to signalR hub.
            hubConnection.Start().ContinueWith((result) =>
            {                    
                hubProxy.Invoke("SendAll", message);
            });
        }

方法4创建单例集线器

public sealed class SignalRConnectionFactory : ISignalRConnectionFactory
{
    /// <summary>
    /// The instance.
    /// </summary>
    private static volatile SignalRConnectionFactory instance;

    /// <summary>
    /// The sync root.
    /// </summary>
    private static object syncRoot = new Object();

    /// <summary>
    /// The signal r host.
    /// </summary>
    private string signalRHost = ConfigurationManager.AppSettings["SignalRHost"];

    /// <summary>
    /// The hub connection.
    /// </summary>
    private HubConnection hubConnection;

    /// <summary>
    /// Prevents a default instance of the <see cref="SignalRConnectionFactory"/> class from being created.
    /// </summary>
    private SignalRConnectionFactory()
    {
        this.hubConnection = new HubConnection(this.signalRHost + "/signalr", useDefaultUrl: false);
        this.hubConnection.Credentials = CredentialCache.DefaultNetworkCredentials;
    }

    /// <summary>
    /// Gets the instance.
    /// </summary>
    public static SignalRConnectionFactory Instance
    {
        get
        {
            if (instance == null)
            {
                lock (syncRoot)
                {
                    if (instance == null)
                    {
                        instance = new SignalRConnectionFactory();
                    }
                }
            }

            return instance;
        }
    }

    /// <summary>
    /// The create.
    /// </summary>
    /// <returns>
    /// The <see cref="HubConnection"/>.
    /// </returns>
    public HubConnection Create()
    {
        return this.hubConnection;
    }
}
using (var hubConnection = this.connectionFactory.Create())
        {
            // Establish connection to the SignalRHub.
            IHubProxy hubProxy = hubConnection.CreateHubProxy(this.dataCollectionServiceHubName);


            // Start connection to signalR hub.
            hubConnection.Start().ContinueWith((result) =>
            {                    
                hubProxy.Invoke("SendAll", message);
            });
        }