How to use cross-domain connections (CORS - Access Control Allow Origin) with SignalR

Question

Using persistent connections and an ASP.NET JavaScript client, I am trying to connect to a sub-domain not the same as the one the page was served from.

ASP.Net Page

Answer 1

If switching from 0.5.1 to 0.5.2, you may have had the following:

$.connection.hub.start({ transport: 'longPolling', xdomain: true }, function () {...

Which can be changed to:

$.connection.hub.start({ jsonp: true }, function () {...

Answer 2

In Signalr2, you can use the pre-release of Microsoft.Owin.Cors, currently 3.0.0-rc1 as of writing this: Microsoft.Owin.Cors.

More information can be found here:

• http://www.asp.net/signalr/overview/signalr-20/hubs-api/hubs-api-guide-javascript-client
• http://www.asp.net/signalr/overview/signalr-20/getting-started-with-signalr-20/tutorial-getting-started-with-signalr-20

Answer 3

You need to do one of the following to make it work:

• Set up $.connection.hub.url = 'http://subdomain.domain.com/signalr';, pointing to your subdomain.

• Enable cross domain on the server:

  RouteTable.Routes.MapHubs(new HubConfiguration()
  {
    EnableCrossDomain = true
  });
  

Answer 4

In the current version of SignalR, using the now separate CORS package, the API for this has changed to:

public void Configuration(IAppBuilder app)
{
    app.Map("/signalr", map =>
    {
        map.UseCors(CorsOptions.AllowAll);
        var hubConfiguration = new HubConfiguration
        {
        };
        map.RunSignalR(hubConfiguration);
    });
}

See ASP.NET SignalR Hubs API Guide - JavaScript Client.

Answer 5

What really have solved my issue was:

1 - Add this to global.asax:

RouteTable.Routes.MapHubs(new HubConfiguration() { 
    EnableCrossDomain = true 
});

2- Set up the web.config of my web project to enable the cross-domain:

<system.webServer>
    <httpProtocol>
        <customHeaders>
            <add name="Access-Control-Allow-Origin" value="*" />
            <add name="Access-Control-Allow-Headers" value="Content-Type" />
        </customHeaders>
    </httpProtocol>
</system.webServer>

3- Then I change the implementation on my html, changing the $.connection() to as follow:

var connection = $.hubConnection('http://localhost.my:8081/signalr');
var chatHubProxy = connection.createHubProxy('chatHub');

Versions I'm using:

• signalR-1.1.0

• jquery.signalR-1.1.3.js

• dot.net 4.0

Answer 6

var connection = $.connection('http://somecrossdomainurl/echo')
connection.start({ transport: 'longPolling', xdomain: true });

https://github.com/SignalR/SignalR/wiki/SignalR-JS-Client