Develop Reference

SignalR pending Request In IIS

We have a web application with .NET 5 MVC, in which after authentication process we Open the signalR connection.
When we load the same page by duplicate the browser instance, the rest of the user get struct and application stops responding. Also other users are also not able use application.
While viewing currently processing request in IIS -> Worker process it shows all pending connection request with high time elapsed for the open browser instances.
once we close the browser tab, application starts working for other user.
Kindly suggest the solution for the same.
find the below mention code
var startConnection = function () {
var signalRConnId = '';
if (sr_connection == null && spGeneral.useSignalR) {
sr_connection = new signalR.HubConnectionBuilder().withUrl("/SignalRHub").withAutomaticReconnect().build();
return sr_connection.start().then(function () {
signalRConnId = sr_connection.connection.connectionId;
console.log('Signal R Connection Id : ' + signalRConnId);
console.log('Signal R Started');
return sr_connection;
}).catch(function (err) {
console.error('Signal R Notification Error: ' + err.toString());
});
}
else {
return sr_connection
}
}
Server code
public Task SendNotificationAsync(string subcriber,object data)
{
return _hub.Clients.All.SendAsync(subcriber, data);
}

It was a problem of windows 10 with IIS 10. We shifted our web app deployment to windows server 2016. So it got resolved.
It seems a problem with Window 10.

Authenticate user when printing from IOS device

I've built a small App that register a service that looks like an Airpint to IOS device.
I have little knowledge on IPP programming.
I am using Monozeroconf Dll and C# to register my service etc... and that's all work fine but i would like to display a popup to enter Username and password so that i can identify the person that is printing.
Can someone help or point me to the right direction.
Thanks in advance.

Just in case someone out there has been struggling with this, here's my code
if (!HttpListener.IsSupported)
{
Console.WriteLine("Server does not support Http Listener.");
return;
}
// URI prefixes required,
if (prefixes == null || prefixes.Length == 0)
throw new ArgumentException("prefixes required");
// Create a listener.
HttpListener listener = new HttpListener();
// Add the prefixes.
foreach (string s in prefixes)
{
listener.Prefixes.Add(s);
}
listener.Start();
listener.AuthenticationSchemes = AuthenticationSchemes.Basic;
Console.WriteLine("About to listen to " + prefixes[0].ToString());
if (listener.IsListening) {
Console.WriteLine("Currently Listening to " + prefixes[0].ToString());
}
//Wait until a connection is made before continuing
//allDone.WaitOne();
// Note: The GetContext method blocks while waiting for a request.
HttpListenerContext context = listener.GetContext();
//Retrives Username and password from the Http Request
var hlbi = (HttpListenerBasicIdentity)context.User.Identity;
Console.WriteLine("Username: " + hlbi.Name);
Console.WriteLine("Password: " + hlbi.Password);
listener.Stop();`
for some reason my firewall was blocking connection on Getcontext(), so i had to put an excpetion on the IPP port 631.(not the application)

System.Net.Sockets.SocketException: Could not resolve host - Self-hosted Nancy app on Mono

I have the following code in my Program.cs to start a self-hosted nancy app on Mono 4.2.2.
public static void Main (string[] args)
{
var uri = "";
if(ReflectConfiguration.CurrentEnviroment == ReflectConfiguration.Environments.Production || ReflectConfiguration.CurrentEnviroment == ReflectConfiguration.Environments.Staging)
{
uri = string.Format("http://localhost:{0}", Environment.GetEnvironmentVariable("PORT").ToString());
}
else if(ReflectConfiguration.CurrentEnviroment == ReflectConfiguration.Environments.Development)
{
uri = string.Format("http://localhost:8888");
}
Console.WriteLine("Starting Reflect.Web application on " + uri);
// initialize an instance of NancyHost
var host = new NancyHost(new Uri(uri));
host.Start(); // start hosting
// check if we're running on mono
if (Type.GetType("Mono.Runtime") != null)
{
// on mono, processes will usually run as daemons - this allows you to listen
// for termination signals (ctrl+c, shutdown, etc) and finalize correctly
UnixSignal.WaitAny(new[] {
new UnixSignal(Signum.SIGINT),
new UnixSignal(Signum.SIGTERM),
new UnixSignal(Signum.SIGQUIT),
new UnixSignal(Signum.SIGHUP)
});
}
else
{
Console.ReadLine();
}
host.Stop(); // stop hosting
}
This code ran fine for months. Just now this error started showing up:
System.Net.Sockets.SocketException: Could not resolve host '+'
on this line:
host.Start(); // start hosting
I am not aware of any updates I have made recently to any dependency.
Has anyone ever come across this before? And why the '+' sign?

+ can be part of the "URI prefix string" that .NET's HttpListener (not sure about mono) uses to determine where it should host the application, check out the HttpListener's Class remarks for more information:
Similarly, to specify that the HttpListener accepts all requests sent to a port, replace the host element with the "+" character, "https://+:8080". The "*" and "+" characters can be present in prefixes that include paths.
My guess is that your code is checking ReflectConfiguration.CurrentEnviroment and missing the cases you're selecting for.
Is there not an environment configured/present? or are you not in Production, Staging, or Development? What is the value of uri when you create a new URI object?

Error using Azure Service Bus Subscription OnMessageAsync event

We are using Azure Service Bus in our project and while reading messages from service bus topic/subscription.
We are using subscriptionClient.OnMessageAsync event in conjunction with onMessageOptions.ExceptionReceived.
Let me write down the steps we followed to reproduce the issue we are facing.
Create a service bus namespace with default config in the azure portal
Create a topic inside it with default config in the azure portal
Create a subscription inside it with default config in the azure portal
Create a console app and paste the code added below
Connect the service bus using Service Bus Explorer
Run the console app
Send a few test messages from service bus explorer & watch the console app window
Though the messages are processed successfully every time the control is going inside the ExceptionReceived method
Here's the code:
class Program
{
static void Main()
{
var subscriptionClient = SubscriptionClient.CreateFromConnectionString
(
"servicebusendpointaddress",
"topicname",
"subscriptionname",
ReceiveMode.PeekLock
);
var onMessageOptions = new OnMessageOptions();
onMessageOptions.ExceptionReceived += OnMessageError;
subscriptionClient.OnMessageAsync(OnMessageReceived, onMessageOptions);
Console.ReadKey();
}
private static void OnMessageError(object sender, ExceptionReceivedEventArgs e)
{
if (e != null && e.Exception != null)
{
Console.WriteLine("Hey, there's an error!" + e.Exception.Message + "\r\n\r\n");
}
}
private static async Task OnMessageReceived(BrokeredMessage arg)
{
await arg.CompleteAsync();
Console.WriteLine("Message processing done!");
}
}
Are we missing something here?
Also one point to mention is that is we enable ‘autocomplete’ and remove the await arg.CompleteAsync(); then this is not happening.
var onMessageOptions = new OnMessageOptions() { AutoComplete = true};
In both the cases the messages are being processed successfully & removed from the subscription immediately.

You might be getting this because you are debugging and stepping though the code i.e. the lock expires. The LockDuration by default is 60 seconds.
You can try setting your OnMessageOptions() like this to test:
var onMessageOptions = new OnMessageOptions() { AutoRenewTimeout = TimeSpan.FromMinutes(1) };

Client Not read remote MSMQ queue, but can send to remote queue

I have Windows Service developed in C#
I have Windows Server 2012 with 2 private queues: queueRequests and queueResponses.
My queues are not transactional.
I have Client that execute Console Application with credentials MyDomain\UserDeploy .
Windows Service in Server is executed with credentials MyDomain\UserAgent.
MyDomain\UserAgent and MyDomain\UserDeploy user has Full control about queues: queueRequests and queueResponses.
Server and Client are in the same MyDomain.
Console Application Client to send message and read message from/to private queue in Server.
Windows Service in Server to send message and read message from/toprivate queue.
Execution Steps:
Console Application Client send Message A to private Queue
queuerequests in Server
Windows Service read Message A from private queue queuerequests
Windows Service sendMessage B to private queue queueresponses
Console Application Client read Message B from private queue
queueresponses.
It was working all steps.
Now, I don't know the reason, the step 4 fails. Client Not reads message from remote queue.
I don't understand why: Client can send message to queue, but not reads from queue.
I get a MessageQueueException but exception.Message is empty.
Any suggestions for get good troubleshooting ?
Fragment code:
const string ForSend = #"FormatName:DIRECT=OS:{0}\private$\DeploymentCommands";
const string ForRead = #"FormatName:DIRECT=OS:{0}\private$\DeploymentResponses";
private DeploymentResponse WaitForResponse()
{
try
{
Message rsp = colaStatus.ReceiveByCorrelationId(correlationId, new TimeSpan(0, timeOut, 0));
DeploymentResponse ret = rsp.Body as DeploymentResponse;
Console.WriteLine("Respuesta WaitForResponse:" + ret.DeploymentId + " - " + ret.Status);
Trace.WriteLine("Respuesta WaitForResponse:" + ret.DeploymentId + " - " + ret.Status);
return ret;
}
catch (MessageQueueException ex)
{
Console.WriteLine("Error WaitForResponse in remote server " + remoteServer + ". " + ex.Message);
Trace.WriteLine("Error WaitForResponse in remote server " + remoteServer + ". " + ex.Message);
return null;
}
catch (Exception)
{
throw;
}
}
More about MessageQueueException .
I get
Message: null
MessageQueueErrorCode -2147023169
ErrorCode -2147467259
but not found that code in MessageQueueErrorCode Enumeration.
-2147023169 value. In Hex: 800706BF
-2147467259 value. In Hex: 80004005
Not much info about those codes. Only I get:
0x80004005 -2147467259 E_Fail
0x800706BF -2147023169 PRC_S_Call_Failed_DNE
Windows Update Codes
Full trace exception:
Message: - MessageQueueErrorCode -2147023169 - ErrorCode-2147467259
StackTrace:
at System.Messaging.MessageQueue.MQCacheableInfo.get_ReadHandle()
at System.Messaging.MessageQueue.ReceiveBy(String id, TimeSpan timeout,
Boolean remove, Boolean compareId, Boolean throwTimeout,
MessageQueueTransaction transaction, MessageQueueTransactionType
transactionType)
at System.Messaging.MessageQueue.ReceiveByCorrelationId(String
correlationId, TimeSpan timeout)
at DeploymentAgent.Client.DeploymentInvoker.WaitForResponse()

Things you might try:
Changing queue permissions - see here, try setting permission to "Everyone" (for the test only).
Try setting AllowNonauthenticatedRPC in registry - details here

May you should consider to use public instead of private queues. Read the following articles of the advantages of public queues:
Destination Queues
Public and private queues