How to resolve SignalR Hub connection issue from Client side Javascript code

Mayuri Barve 1

I have web application developed in .NET 5.0. This web application calls Web APIs to fetch information from SQL DB. Web and API applications are two separate applications hosted in Azure. I want to push some real time data every 2 minutes to all clients when ever any record is inserted or updated in DB. I am using SignalR in my web application to achieve this. I have added required package references on server side and signalR.js on client side. Have done all the configurations on both side.

Server side: Created a Hub class with SendMessage method. I have also used IHostedService for periodic execution and calling hub's SendMessage method from IHostedService Start event to send updated data to all Clients.

Client side: Establishing connection to the hub as

When I run the application it is giving error: Failed to complete negotiation with the server: TypeError: Failed to fetch

Error is occurring in FetchHttpClient.js file.

Can anyone please suggest what is missing here?

Thanks.

JasonPan - MSFT 4,476 Reputation points Microsoft Vendor

2024-05-16T11:20:17.1333333+00:00

Hi @Mayuri Barve,

Since there is no more error details, it's hard for us to find the root cause.

So please try to enable the Client-Side logging first and share the logs with us, then we will help you to check it.

Best Regards

Jason

Mayuri Barve 1

It is giving following error:

Failed to complete negotiation with the server: Error: System.MissingMethodException: Method not found: 'Microsoft.AspNetCore.Http.Features.IFeatureCollection Microsoft.AspNetCore.Connections.ConnectionContext.get_Features()'

below is my client side javascript code

var hubConnection = new signalR.HubConnectionBuilder()

    .withUrl("/notifyHub")

    .configureLogging(logging => {

        logging.AddConsole();

        logging.SetMinimumLevel(LogLevel.Debug);

    })

    .build();



hubConnection.on("ReceiveMessage", (message) => {

    $("#Message").val(message);

   

});

hubConnection.start()

    .then(function () {

        alert('connection established!');

        console.log("Hub Connection established.");

    })

    .catch(function (err) {

        alert(err);

        return console.error(err.toString());

    });

Below is Server side Hub definition

namespace SignalRMVCSample.Hubs

{

public class NotifyHub : Hub

{

    public async Task SendMessage(string message)

    {

        await Clients.All.SendAsync("ReceiveMessage", message);

    }

}

}

Startup.cs file entries

ConfigureServices

        services.AddSignalR();

Configure

            endpoints.MapHub<NotifyHub>("/notifyHub");

JasonPan - MSFT 4,476 Reputation points Microsoft Vendor

2024-05-17T13:35:07.4266667+00:00

Hi @Mayuri Barve,

Please share the full error details for me, thanks.

You also can enable server-side logging and share with us.

Best Regards

Jason

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How to resolve SignalR Hub connection issue from Client side Javascript code