RequestHandler to set Proxy Auth not working

[SorceryAdmin]

for the classes:

public class CustomRequestContext : RequestContextHandler
{

    public WebProxy CurrentProxy { get; set; }
    public bool blockWebRTC { get; set; } = true;
    public CustomRequestContext(bool blockRTC) : base()
    {
        blockWebRTC = blockRTC;

     
    }
    protected override async void OnRequestContextInitialized(IRequestContext requestContext)
    {
        requestContext.SetPreference("credentials_enable_service", true, out _);
        if (CurrentProxy != null)
        {
            requestContext.SetPreference("webrtc.multiple_routes_enabled", false, out _);
            requestContext.SetPreference("webrtc.nonproxied_udp_enabled", false, out _);
            if (blockWebRTC)
                requestContext.SetPreference("webrtc.ip_handling_policy", "disable_non_proxied_udp", out _);

            requestContext.SetProxy(CurrentProxy.Address.Scheme, CurrentProxy.Address.Host, CurrentProxy.Address.Port, out string error);
            requestContext.SetPreference("intl.accept_languages", "en-US,en;q=0.9,en", out string error2);
        }
    }

    protected override IResourceRequestHandler GetResourceRequestHandler(IBrowser browser, IFrame frame, IRequest request, bool isNavigation, bool isDownload, string requestInitiator, ref bool disableDefaultHandling)
    {
        return base.GetResourceRequestHandler(browser, frame, request, isNavigation, isDownload, requestInitiator, ref disableDefaultHandling);
    }


}

public class ProxyAuthRequestHandler : CefSharp.Handler.RequestHandler
{
    public NetworkCredential Credentials { get; set; }
    protected override bool GetAuthCredentials(IWebBrowser chromiumWebBrowser, IBrowser browser, string originUrl, bool isProxy, string host, int port, string realm, string scheme, IAuthCallback callback)
    {
        File.WriteAllText(@$"D:\html\{DateTime.Now.Ticks}.json", $@"{new { originUrl , isProxy , host , port, realm , scheme }}");

        if (Credentials != null && isProxy == true)
        {
            callback.Continue(Credentials.UserName, Credentials.Password);
            return true;
        }
        return false;
    }
}

and calling in file BrowserProcessHandler.cs.cs in the method CreateBrowser

        Task IOutOfProcessClientRpc.CreateBrowser(IntPtr parentHwnd, string url, int id)
        {
            //Debugger.Break();

            return CefThread.ExecuteOnUiThread(() =>
            {
                var requestContextSettings = new RequestContext(new CustomRequestContext( false) { CurrentProxy = this.Proxy });
                var browser = new OutOfProcessChromiumWebBrowser(_outOfProcessServer, id, url, requestContextSettings);
                browser.RequestHandler = new ProxyAuthRequestHandler() { Credentials = (NetworkCredential)Proxy.Credentials };
                var windowInfo = new WindowInfo();
                windowInfo.WindowName = "BrowserProcess";
                windowInfo.SetAsChild(parentHwnd);
                //Disable Window activation by default
                //https://bitbucket.org/chromiumembedded/cef/issues/1856/branch-2526-cef-activates-browser-window
                windowInfo.ExStyle |= OutOfProcessChromiumWebBrowser.WS_EX_NOACTIVATE;
                browser.CreateBrowser(windowInfo);
                _browsers.TryAdd(id, browser);

                return true;
            });
        }

CustomRequestContext is set and the proxy is done but it promps as is show in the image for a proxy credentials the GetAuthCredentials method is never called. on non auth proxies it works all fine cause CustomRequestContext sets correctly the proxy.

probably I'm missing something on my understanding of the project but I'm unable to make the Request Handler to work.

[amaitland]

CustomRequestContext is set and the proxy is done but it promps as is show in the image for a proxy credentials the GetAuthCredentials method is never called. on non auth proxies it works all fine cause CustomRequestContext sets correctly the proxy.

What do you mean by the proxy is done? I'm not sure I understand.

Have you attached the debugger and stepped through your code?

You can programmatically launch the debugger.
https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.debugger.launch?view=net-9.0

Another option is to test your code in say https://github.com/cefsharp/CefSharp.MinimalExample then you can directly debug in the same process, once that's working you can move it across.

What CefSharp version are you using? Need more information to understand what's going on.

[SorceryAdmin]

What do you mean by the proxy is done? I'm not sure I understand.
I mean it does try to use the proxy.
but it never calls the RequestHandler to handle Authentication
Have you attached the debugger and stepped through your code?
yes is never called.

What CefSharp version are you using?
tried from 138 to 141.0.110

[amaitland]

I've upgraded the main repo to M141 and made a change that should hopefully help.

Specifically commit f3e2571

The WinForms/Wpf/OffScreen implementations have some default command line args set. One being to disable the login prompt so GetAuthCredentials works. Please see if this resolves your issue.