Authenticate a .NET Core 2.1 SignalR console client to a web app that uses "Identity as UI"

Question

Using .NET Core 2.1 & VS2017 preview 2 I created a simple web server with "Identity as UI" as explained here and then added a SignalR chat following this.

In particular I have:

app.UseAuthentication();
app.UseSignalR((options) => {
    options.MapHub<MyHub>("/hubs/myhub");
});

..

[Authorize]
public class MyHub : Hub

..

"iisSettings": {
  "windowsAuthentication": false,
  "anonymousAuthentication": true,
     "iisExpress": {
     "applicationUrl": "http://localhost:5000",
     "sslPort": 0

I start the debugger which brings the browser, register a user and log in, then go to http://localhost:5000/SignalRtest (my razor page that uses signalr.js) and verify the chat works fine.

I now try to create a .NET Core console app chat client:

class Program
{
    public static async Task SetupSignalRHubAsync()
    {
        var hubConnection = new HubConnectionBuilder()
                    .WithUrl("http://localhost:5000/hubs/myhub")
                    .Build();

        await hubConnection.StartAsync();
        await hubConnection.SendAsync("Send", "consoleapp");
    }

    public static void Main(string[] args)
    {
        SetupSignalRHubAsync().Wait();
    }
}

My issue is I don't know how to authenticate this client ?

EDIT:

(from https://github.com/aspnet/SignalR/issues/2455)

"The reason it works in the browser is because the browser has a Cookie from when you logged in, so it sends it automatically when SignalR makes it's requests. To do something similar in the .NET client you'll have to call a REST API on your server that can set the cookie, scoop the cookie up from HttpClient and then provide it in the call to .WithUrl, like so:

var loginCookie = /* get the cookie */
var hubConnection = new HubConnectionBuilder()
    .WithUrl("http://localhost:5000/hubs/myhub", options => {
        options.Cookies.Add(loginCookie);
    })
    .Build();

I now put a bounty on this question, hoping to get a solution showing how to authenticate the .NET Core 2.1 SignalR console client with a .NET Core 2.1 web app SignalR server that uses "Identity as UI". I need to get the cookie from the server and then add it to SignalR HubConnectionBuilder (which now have a WithCookie method).

Note that I am not looking for a third-party solutions like IdentityServer Thanks!

Answer 1

I did ended up getting this to work like this:

On the server I scaffolded Login and then in Login.cshtml.cs added

[AllowAnonymous]
[IgnoreAntiforgeryToken(Order = 1001)]
public class LoginModel : PageModel

That is I do not require the anti forgery token on login (which doesn't make sense anyway)

The client code is then like this:

HttpClientHandler handler = new HttpClientHandler();
CookieContainer cookies = new CookieContainer();
handler.CookieContainer = cookies;
HttpClient client = new HttpClient(handler);

var uri = new Uri("http://localhost:5000/Identity/Account/Login");
string jsonInString = "Input.Email=myemail&Input.Password=mypassword&Input.RememberMe=false";
HttpResponseMessage response = await client.PostAsync(uri, new StringContent(jsonInString, System.Text.Encoding.UTF8, "application/x-www-form-urlencoded"));
var responseCookies = cookies.GetCookies(uri);
var authCookie = responseCookies[".AspNetCore.Identity.Application"];

var hubConnection = new HubConnectionBuilder()
        .WithUrl("http://localhost:5000/hubs/myhub", options =>
        {
            options.Cookies.Add(authCookie);
        })
        .Build();

await hubConnection.StartAsync();
await hubConnection.SendAsync("Send", "hello!");

(of course password will be elsewhere in deployment)