DevToolsContext vs Task.Delay (nugget build 2.0.83)

[Oberuks]

Hello,

I am using:
Windows Forms App with framework .NET Core 3.1
CefSharp.WinForms.NETCore version 107.1.50
CefSharp.Dom version 2.0.83

If I use Task.Delay in the context of DevToolsContext then an error occurs:

CefSharp.Dom.TargetClosedException: 'Protocol error(Runtime.callFunctionOn): Target closed. (Connection failed to process Runtime.executionContextCreated. Frame 3184B035461ABD0B95E8CAC602552101 not found.    at CefSharp.Dom.Helpers.AsyncDictionaryHelper2.<>c__DisplayClass4_0.<GetItemAsync>b__0() in C:\projects\cefsharp-dom\lib\PuppeteerSharp\Helpers\AsyncDictionaryHelper.cs:line 34
   at CefSharp.Dom.Helpers.TaskHelper.WithTimeout[T](Task1 task, Action timeoutAction, TimeSpan timeout) in C:\projects\cefsharp-dom\lib\PuppeteerSharp\Helpers\TaskHelper.cs:line 130
   at CefSharp.Dom.Helpers.AsyncDictionaryHelper2.GetItemAsync(TKey key) in C:\projects\cefsharp-dom\lib\PuppeteerSharp\Helpers\AsyncDictionaryHelper.cs:line 32
   at CefSharp.Dom.FrameManager.OnExecutionContextCreatedAsync(ContextPayload contextPayload) in C:\projects\cefsharp-dom\lib\PuppeteerSharp\FrameManager.cs:line 234
   at CefSharp.Dom.FrameManager.OnConnectionMessageReceived(Object sender, MessageEventArgs e) in C:\projects\cefsharp-dom\lib\PuppeteerSharp\FrameManager.cs:line 163)'

Why is this happening?

My code:

using System;
using System.Threading.Tasks;
using System.Windows.Forms;
using CefSharp.WinForms;
using CefSharp.Dom;

namespace WinFormsApp4
{
    public partial class Form1 : Form
    {
        private readonly ChromiumWebBrowser _browser;

        public Form1()
        {
            InitializeComponent();

            _browser = new ChromiumWebBrowser("https://developers.google.com/web/");
            panel2.Controls.Add(_browser);
        }

        private async void Form1_Load(object sender, EventArgs e)
        {
            await _browser.WaitForInitialLoadAsync();
            await TestDomAsync();
        }

        private async Task TestDomAsync()
        {
            await using var devToolsContext = await _browser.CreateDevToolsContextAsync();
            var inputSelector = "input[name='q']";
            var waitForSelectorOptions = new WaitForSelectorOptions {Timeout = 30000};
            var emailInput = await devToolsContext.WaitForSelectorAsync(inputSelector, waitForSelectorOptions);
            await emailInput.TypeAsync("Headless");

            // this line rise CefSharp.Dom.TargetClosedException
            await Task.Delay(1000);
           
            var emailInput1 = await devToolsContext.WaitForSelectorAsync(inputSelector, waitForSelectorOptions);
            await emailInput1.TypeAsync(" Chrome");
        }
    }
}

My test solution: WinFormsApp4.zip

[amaitland]

First step is to create a failing xunit test from your example and submit a PR.

https://github.com/cefsharp/CefSharp.Dom/blob/main/lib/PuppeteerSharp.Tests/WaitTaskTests/DevToolsContextWaitForTests.cs

[Oberuks]

PR submited
#45

[Oberuks]

I made a mistake in testing product versions. There is no problem in the current repository at github.com CefSharp.Dom.
The problem I described is in the nugget build 2.0.83 dated 9/12/2022.

[amaitland]

There is no problem in the current repository at github.com CefSharp.Dom.
The problem I described is in the nugget build 2.0.83 dated 9/12/2022.

If you look closely you'll see that version 2.0.83 was built from the same commit your PR was based
https://ci.appveyor.com/project/cefsharp/cefsharp-dom/builds/44746155

There were no new changes/fixes until today.

The difference is likely the Chromium version you were testing against. Likely the sequence or timing changed in the CDP events.

[amaitland]

Try version 2.0.86

[Oberuks]

Try version 2.0.86

Thanks, version 2.0.86 doesn't have this problem.

[amaitland]

Thanks for confirming 👍