Remove auth cookie from browser in Xamarin.Forms

Question

I have an app where users are going to share devices. The app uses OAuth 2.0 to sign the user in.(from a provider with IdentityServer4, though the problem occurs on other providers too)

The browser used is:

//Android
public Task OpenBrowser(Uri uri)
{
    var nativeUri = UUri.Parse(uri.AbsoluteUri);

    var builder = new CustomTabsIntent.Builder();
    var launchIntent = builder
        .SetShowTitle(true)
        .Build();

    launchIntent.LaunchUrl(MainActivity, nativeUri);
    return Task.CompletedTask;
}

//iOS
public Task OpenBrowser(Uri uri)
{
    var nativeUrl = new NSUrl(uri.AbsoluteUri);
    var sfViewController = new SFSafariViewController(nativeUrl, false);

    var window = UIApplication.SharedApplication.KeyWindow;
    var vc = window.RootViewController;

    while (vc.PresentedViewController != null)
    {
        vc = vc.PresentedViewController;
    }

    vc.PresentViewControllerAsync(sfViewController, true);
    return Task.CompletedTask;
}

I also tried to use the new WebAuthenticator from Xamarin.Forms.

Since I’m making an app where users share devices I have to let them sign out, to remove the token from internal storage. The problem arises when there is no Internet, as I can only remove the token in the app, and not the authentication/token or what is cached in the Browser. Meaning, the next user to try (when the internet is back) will get automatically signed in with the previous users' credentials..

I tried to remove cookies with NSHttpCookieStorage.SharedStorage and CookieManager.Instance, but they have empty cookie storages.

Any solution is welcome, either to remove the cookie from the browser or to create a browser which clears cookies instantly (as I don't need the cookies in the browser after auth is done anyway).

Remove auth cookie from browser in Xamarin.Forms

0 Answers