HttpListener si blocca sulla macchina quad core Win 2008 Server R2

Question

abbiamo creato am servizio Web di Exchange notifiche push Listener in base alla HttpListener nel libro EWS (codice qui sotto). Ha funzionato bene su una vittoria 2008 Server con un singolo xeon nucleo. Ora ci siamo trasferiti in un R2 Server Win 2008 con una CPU Opteron quad core e si blocca subito dopo il listener viene inizializzato con HTTPListenerExceptions. Ora, poiché non è cambiato nulla ma il server ho pensato che potrebbe avere qualcosa a che fare con il multi threading. Forse someon può consigliare, grazie.

public class PushNotificationClient
{
    private uint portNumber;
    private NotificationEventsReceived eventHandler;
    private bool isListening = false;
    private ManualResetEvent stopEvent = new ManualResetEvent(false);
    private bool shouldStop = false;
    private XmlNamespaceManager mgr;
    private XmlSerializer ser;

    /// <summary>
    /// Constructor
    /// </summary>
    /// <param name="portNumber">Port number to listen on</param>
    /// <param name="eventHandler">delegate to call when notifications are
    /// received</param>
    ///
    public PushNotificationClient(
    uint portNumber,
    NotificationEventsReceived eventHandler)
    {
        this.portNumber = portNumber;
        if (eventHandler == null)
        {
            throw new ArgumentNullException("eventHandler");
        }
        this.eventHandler = eventHandler;
        // namespace manager is used for XPath queries when parsing the request
        //
        this.mgr = new XmlNamespaceManager(new NameTable());
        this.mgr.AddNamespace("t",
        "http://schemas.microsoft.com/exchange/services/2006/types");
        this.mgr.AddNamespace("m",
        "http://schemas.microsoft.com/exchange/services/2006/messages");
        // XmlSerializer is used to convert SendNotification elements into proxy
        // class instances
        //
        this.ser = new XmlSerializer(typeof(SendNotificationResponseType));
    }

    /// <summary>
    /// Start Listening
    /// </summary>
    public void StartListening()
    {
        VerifyNotListening();
        this.stopEvent.Reset();
        this.shouldStop = false;
        // Run the listener on a background thread so we are not blocked
        //
        ThreadPool.QueueUserWorkItem(new WaitCallback(ListenOnThread));
    }

    /// <summary>
    /// Stop Listening
    /// </summary>
    public void StopListening()
    {
        VerifyListening();
        // Set the stopEvent. This will cause the worker thread to close our and
        // dispose of the HttpListener and exit the thread
        //
        this.stopEvent.Set();
    }

    /// <summary>
    /// Thread pool method to start listening on the background thread
    /// </summary>
    /// <param name="state">State - ignore</param>
    ///
    private void ListenOnThread(object state)
    {
        using (HttpListener listener = new HttpListener())
        {
            listener.Prefixes.Add(
                String.Format(
                "http://+:{0}/PushNotificationsClient/",
                this.portNumber.ToString()));
            listener.Start();
            this.isListening = true;
            while (!shouldStop)
            {
                IAsyncResult asyncResult = listener.BeginGetContext(
                AsyncCallbackMethod, listener);
                // Wait on either the listener or the stop event
                //
                int index = WaitHandle.WaitAny(
                new WaitHandle[] { stopEvent, asyncResult.AsyncWaitHandle });
                switch (index)
                {
                    case 0:
                        // Stop event was triggered.
                        //
                        shouldStop = true;
                        break;
                    case 1:
                        // Notification was received. Just loop around so we can call
                        // BeginGetContext again
                        //
                        break;
                }
            }
            listener.Stop();
        }
        this.isListening = false;
    }

    /// <summary>
    /// Async method called once we receive a request
    /// </summary>
    /// <param name="result">Async result containing our HttpListener</param>
    ///
    private void AsyncCallbackMethod(IAsyncResult result)
    {
        HttpListener listener = result.AsyncState as HttpListener;
        if (!this.isListening)
        {
            // Our callback gets fired when we stop the listener too. If it is not
            // listening, just return.
            //
            return;
        }
        HttpListenerContext context = listener.EndGetContext(result);
        SendNotificationResponseType request;
        // Now use the XML serializer to turn the XML into a notification
        // serialization type...
        //
        XmlDocument doc = new XmlDocument();
        try
        {
            doc.LoadXml(
            new StreamReader(
            context.Request.InputStream).ReadToEnd());
            // retrieve the first SendNotification element (there should be only one).
            //
            XmlNodeList nodes = doc.SelectNodes("//m:SendNotification[1]", this.mgr);
            if (nodes.Count == 0)
            {
                // this wasn't a SendNotification request or it was malformed or
                // something like that.
                FailRequest(context);
                return;
            }
            string sendNotification = nodes[0].OuterXml;
            using (MemoryStream ms = new MemoryStream())
            {
                byte[] bytes = Encoding.UTF8.GetBytes(sendNotification);
                ms.Write(bytes, 0, bytes.Length);
                ms.Flush();
                ms.Position = 0L;
                request = (SendNotificationResponseType)this.ser.Deserialize(ms);
            }
        }
        catch (XmlException)
        {
            // Failed to deserialize request.
            //
            FailRequest(context);
            return;
        }
        // Fire the delegate
        //
        NotificationResponse response = eventHandler(
        this, /* sender */
        request.ResponseMessages.Items[0]
        as SendNotificationResponseMessageType);
        GenerateResponseXML(context, response);
    }

    /// <summary>
    /// Fail the request. Right now we don't differentiate between reasons why it
    /// failed.
    /// </summary>
    /// <param name="context">Request context</param>
    ///
    private void FailRequest(HttpListenerContext context)
    {
        context.Response.ContentEncoding = Encoding.UTF8;
        context.Response.ContentType = "text/xml; charset=utf-8";
        context.Response.ProtocolVersion = new Version(1, 1, 0, 0);
        context.Response.StatusCode = 400;
        string response = "<?xml version=\"1.0\"?>" +
        "<Error>Bad Request</Error>";
        byte[] responseBytes = Encoding.UTF8.GetBytes(response);
        context.Response.ContentLength64 = responseBytes.Length;
        context.Response.OutputStream.Write(
        responseBytes, 0, responseBytes.Length);
        context.Response.OutputStream.Flush();
    }

    /// <summary>
    /// Generate the response xml
    /// </summary>
    /// <param name="context">call context</param>
    /// <param name="response">The response enum value</param>
    ///
    private void GenerateResponseXML(
    HttpListenerContext context,
    NotificationResponse response)
    {
        StringBuilder builder = new StringBuilder();
        builder.AppendLine("<?xml version=\"1.0\"?>");
        builder.AppendLine("<s:Envelope xmlns:s= " +
        "\"http://schemas.xmlsoap.org/soap/envelope/\">");
        builder.AppendLine("<s:Body>");
        builder.AppendLine(" <SendNotificationResult " +
        "xmlns=\"http://schemas.microsoft.com/exchange/services/2006/messages\">");
        builder.AppendFormat(" <SubscriptionStatus>{0}</SubscriptionStatus>\r\n",
        response.ToString());
        builder.AppendLine(" </SendNotificationResult>");
        builder.AppendLine("</s:Body>");
        builder.AppendLine("</s:Envelope>");
        context.Response.ContentEncoding = Encoding.UTF8;
        context.Response.ContentType = "text/xml; charset=utf-8";
        context.Response.ProtocolVersion = new Version(1, 1, 0, 0);
        context.Response.StatusCode = 200;
        byte[] responseBytes = Encoding.UTF8.GetBytes(builder.ToString());
        context.Response.ContentLength64 = responseBytes.Length;
        context.Response.OutputStream.Write(
        responseBytes, 0, responseBytes.Length);
        context.Response.OutputStream.Flush();
    }

    /// <summary>
    /// Returns true if the listener is listening
    /// </summary>
    public bool IsListening
    {
        get
        {
            return isListening;
        }
    }
    /// <summary>
    /// Verifies that the listener isn't listening
    /// </summary>
    private void VerifyNotListening()
    {
        if (isListening)
        {
            throw new PushNotificationStateException("Cannot perform this operation " +
            "when listening");
        }
    }

    /// <summary>
    /// Verifies that the listener is listening
    /// </summary>
    private void VerifyListening()
    {
        if (!isListening)
        {
            throw new PushNotificationStateException("Cannot perform this operation " +
            "when not listening");
        }
    }


}

Answer 1

Sarebbe utile se ci dove l'inizializzazione è stata fallendo hai detto, ma ho il sospetto che si sta cercando sia di registrare un URI che non è stata attivata con il comando netsh, o si sta cercando di registrare un URI che qualche altro processo ha già registrato.

Documentazione per tale eccezione dice, in parte :

  

HttpListenerException sarà gettato   se i tentativi HttpListener a   registrare un Uniform Resource Identifier   (URI) il prefisso che è già   registrati.

ha qualche altro processo già registrato http://+:{0}/PushNotificationsClient/? Ti sei ricordato di eseguire il comando netsh per registrare l'URI sulla porta corretta e consentire l'ascolto?