Error: Uncaught (in promise): Failed to connect. Error: Error during negotiation request

[SemVC7]

Hi there,

Cannot find a way to make connection from Angular app to ChatHub.

Angular 5 app:
"signalr": "^2.2.3"
"ng2-signalr": "^5.0.0"

app.module.ts -->

.net core 2.0 API
"Microsoft.AspNetCore.SignalR (1.0.0-preview2-final)"

Startup.cs -->

Error message when i try to connect from my angular app to the hub:

Any help would be greatly appreciated!

Thanks in advance,
Sem

[jmwaldrip]

Try this c.withCredentials = true;

This fixed it for me.

[TomZak]

Hello

I have the same problem on my soution. I have an old Service written in C# with .Net-Framework 4.6.1. I included following packages:

"Microsoft.AspNet.Cors" version="5.2.7"
"Microsoft.Owin" version="4.0.1"
"Owin" version="1.0"
"Microsoft.AspNet.SignalR" version="2.4.1"
"Microsoft.AspNet.SignalR" version="2.4.1"

My Startup.cs lookes like:
public class StartUp
{
public void Configuration(IAppBuilder app)
{
app.UseCors(CorsOptions.AllowAll);
var config = new HubConfiguration
{
EnableJSONP = true,
EnableDetailedErrors = true,
EnableJavaScriptProxies = true
};
app.MapSignalR(config);
}
}

And in the Service.cs I started the Hub with following code:
private Exception Start_SignalR()
{
try
{
var option = new StartOptions("https://10.31.80.41:18277)
{
ServerFactory = "Microsoft.Owin.Host.HttpListener"
};
SignalR = WebApp.Start(option);
}
catch (Exception ex)
{
return ex;
}
return null;
}

Now I want to connect my Angular-App with the Server:
I installed ng2-signalr with following versions:

Angular 7 app:
"signalr": "^2.4.1",
"ng2-signalr": "^8.0.2",

In the app.module.ts i
export function createConfig(): SignalRConfiguration {
const c = new SignalRConfiguration();
c.url = 'https://10.31.80.41:18277';
c.hubName = 'SignalR_Hub';
c.qs = { user: 'zako' };
c.logging = true;
c.executeEventsInZone = true;
c.executeErrorsInZone = true;
c.executeStatusChangeInZone = true;
c.withCredentials = true;
c.transport = [ConnectionTransports.webSockets, ConnectionTransports.longPolling];
c.jsonp = true;
return c;
}

When I change the Urls to "http://localhost:18277" and run it lokal
(VS2019 with the service and VS-Code an Chrome) everything is ok,
but on the server i got following error:

ConnectionResolver. Resolving...
Creating connecting with...
configuration:[url: 'https://10.31.80.41:18277/'] ...
configuration:[hubName: 'SignalR_Hub'] ...
configuration:[qs: '{"user":"zako"}'] ...
configuration:[transport: '[{"_name":"webSockets"},{"_name":"longPolling"}]'] ...
GET https://10.31.80.41:18277//signalr/negotiate?clientProtocol=2.1&user=zako&connectionData=%5B%7B%22name%22%3A%22signalr_hub%22%7D%5D&callback=jQuery34107495844718916238_1564478570288&_=1564478570290
net::ERR_CONNECTION_RESET
Could not connect
ERROR Error: Uncaught (in promise): Failed to connect. Error: Error during negotiation request.

Can me help anyone?

Thanks in advance,
Thomas