[webview_flutter] WebKitWebResourceError no longer contains information about the failing URL

[Aulig]

Is there an existing issue for this?

• I have searched the existing issues
• I have read the guide to filing a bug

Steps to reproduce

1. Trigger a WebResourceError in an iOS app (e.g. by disabling your internet connection or, on a simulator where you can't do that, by loading a malformatted URL)
2. Look at the content of the WebResouceError

Expected results

Like on Android with WebResourceError.failingUrl there should be some way of accessing the URL that triggered the WebResourceError. This used to be possible in webview_flutter 2.x.x aswell.

Actual results

In webview_flutter 2.x.x the description attribute of the WebResourceError used to contain the domain where the error occurred roughly like this: NSErrorFailingURLKey=example.com

In webview_flutter 4.2.0 it only contains the error description but not the URL.

I thought it was moved to WebKitWebResourceError.domain as that is supposed to contain "A string representing the domain of the error.". However, that always contains the string "NSURLErrorDomain".

Code sample

Code sample

import 'package:flutter/material.dart';
import 'package:webview_flutter/webview_flutter.dart';
import 'package:webview_flutter_android/webview_flutter_android.dart';
import 'package:webview_flutter_wkwebview/webview_flutter_wkwebview.dart';

void main() => runApp(const MaterialApp(home: WebViewExample()));

class WebViewExample extends StatefulWidget {
  const WebViewExample({Key? key}) : super(key: key);

  @override
  State<WebViewExample> createState() => _WebViewExampleState();
}

class _WebViewExampleState extends State<WebViewExample> {
  late final WebViewController _controller;

  @override
  void initState() {
    super.initState();

    _controller = WebViewController();

    _controller.setJavaScriptMode(JavaScriptMode.unrestricted);
    _controller.loadRequest(Uri.parse('https://brokenurl'));

    _controller.setNavigationDelegate(NavigationDelegate(
      onWebResourceError: (WebResourceError webResourceError) {

        if (webResourceError is WebKitWebResourceError) {
          print("WebResourceError: Code ${webResourceError.errorCode} Domain: ${webResourceError.domain} Description: ${webResourceError.description} errorType: ${webResourceError.errorType} isForMainFrame ${webResourceError.isForMainFrame}");
        }
      }
    ));
	
  }

  @override
  Widget build(BuildContext context) {
    return SafeArea(
      child: WebViewWidget(controller: _controller),
    );
  }
}

Screenshots or Video

No response

Logs

Logs

Launching lib/main.dart on iPhone 13 Pro Max in debug mode...
Running Xcode build...
Xcode build done.                                           23.1s
Debug service listening on ws://127.0.0.1:55260/By5UiDWofds=/ws
Syncing files to device iPhone 13 Pro Max...
flutter: WebResourceError: Code -1003 Domain: NSURLErrorDomain Description: A server with the specified hostname could not be found. errorType: null isForMainFrame true

Flutter Doctor output

Doctor output

[✓] Flutter (Channel stable, 3.7.10, on macOS 12.6.3 21G419 darwin-x64, locale en)
    • Flutter version 3.7.10 on channel stable at /Users/administrator/Documents/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 4b12645012 (3 weeks ago), 2023-04-03 17:46:48 -0700
    • Engine revision ec975089ac
    • Dart version 2.19.6
    • DevTools version 2.20.1

[✓] Android toolchain - develop for Android devices (Android SDK version 31.0.0)
    • Android SDK at /Users/administrator/Library/Android/sdk
    • Platform android-33, build-tools 31.0.0
    • ANDROID_HOME = /Users/administrator/Library/Android/sdk
    • ANDROID_SDK_ROOT = /Users/administrator/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jbr/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 17.0.6+0-17.0.6b802.4-9586694)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 14.2)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 14C18
    • CocoaPods version 1.11.2

[✗] Chrome - develop for the web (Cannot find Chrome executable at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome)
    ! Cannot find Chrome. Try setting CHROME_EXECUTABLE to a Chrome executable.

[✓] Android Studio (version 2022.2)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 17.0.6+0-17.0.6b802.4-9586694)

[✓] Connected device (2 available)
    • iPhone 13 Pro Max (mobile) • E27A0EED-67B6-4A6C-AF53-612A32ECB74D • ios        • com.apple.CoreSimulator.SimRuntime.iOS-16-2 (simulator)
    • macOS (desktop)            • macos                                • darwin-x64 • macOS 12.6.3 21G419 darwin-x64

[✓] HTTP Host Availability
    • All required HTTP hosts are available

! Doctor found issues in 1 category.

[darshankawar]

Thanks for the report @Aulig

Can you take a look at the migration guide for the package : https://pub.dev/packages/webview_flutter#migrating-from-30-to-40

Also, below changes related to WebResourceError and see if it helps in your case further or not:

[Aulig]

Thanks for the report @Aulig

Can you take a look at the migration guide for the package : https://pub.dev/packages/webview_flutter#migrating-from-30-to-40

Also, below changes related to WebResourceError and see if it helps in your case further or not:

1826×498 png160,7 kB

Thanks @darshankawar - yes I used the migration guide to migrate to the new onWebResourceError function. The migration docs don't provide any info as to why the failing URL is no longer accessible though.

[stuartmorgan-g]

/cc @bparrishMines for comment

[darshankawar]

Thanks for the update. Seeing the same behavior upon running code sample.

stable, master flutter doctor -v

[!] Flutter (Channel stable, 3.7.12, on macOS 12.2.1 21D62 darwin-x64, locale
    en-GB)
    • Flutter version 3.7.12 on channel stable at
      /Users/dhs/documents/fluttersdk/flutter
    ! Warning: `flutter` on your path resolves to
      /Users/dhs/Documents/Fluttersdk/flutter/bin/flutter, which is not inside
      your current Flutter SDK checkout at
      /Users/dhs/documents/fluttersdk/flutter. Consider adding
      /Users/dhs/documents/fluttersdk/flutter/bin to the front of your path.
    ! Warning: `dart` on your path resolves to
      /Users/dhs/Documents/Fluttersdk/flutter/bin/dart, which is not inside your
      current Flutter SDK checkout at /Users/dhs/documents/fluttersdk/flutter.
      Consider adding /Users/dhs/documents/fluttersdk/flutter/bin to the front
      of your path.
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 4d9e56e694 (3 days ago), 2023-04-17 21:47:46 -0400
    • Engine revision 1a65d409c7
    • Dart version 2.19.6
    • DevTools version 2.20.1
    • If those were intentional, you can disregard the above warnings; however
      it is recommended to use "git" directly to perform update checks and
      upgrades.

[!] Xcode - develop for iOS and macOS (Xcode 12.3)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    ! Flutter recommends a minimum Xcode version of 13.
      Download the latest version or update via the Mac App Store.
    • CocoaPods version 1.11.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] VS Code (version 1.62.0)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.21.0

[✓] Connected device (5 available)
    • SM G975F (mobile)       • RZ8M802WY0X • android-arm64   • Android 11 (API 30)
    • Darshan's iphone (mobile)  • 21150b119064aecc249dfcfe05e259197461ce23 •
      ios            • iOS 14.4.1 18D61
    • iPhone 12 Pro Max (mobile) • A5473606-0213-4FD8-BA16-553433949729     •
      ios            • com.apple.CoreSimulator.SimRuntime.iOS-14-3 (simulator)
    • macOS (desktop)            • macos                                    •
      darwin-x64     • Mac OS X 10.15.4 19E2269 darwin-x64
    • Chrome (web)               • chrome                                   •
      web-javascript • Google Chrome 98.0.4758.80

[✓] HTTP Host Availability
    • All required HTTP hosts are available

! Doctor found issues in 1 category.

[!] Flutter (Channel master, 3.10.0-16.0.pre.23, on macOS 12.2.1 21D62
    darwin-x64, locale en-GB)
    • Flutter version 3.10.0-16.0.pre.23 on channel master at
      /Users/dhs/documents/fluttersdk/flutter
    ! Warning: `flutter` on your path resolves to
      /Users/dhs/Documents/Fluttersdk/flutter/bin/flutter, which is not inside
      your current Flutter SDK checkout at
      /Users/dhs/documents/fluttersdk/flutter. Consider adding
      /Users/dhs/documents/fluttersdk/flutter/bin to the front of your path.
    ! Warning: `dart` on your path resolves to
      /Users/dhs/Documents/Fluttersdk/flutter/bin/dart, which is not inside your
      current Flutter SDK checkout at /Users/dhs/documents/fluttersdk/flutter.
      Consider adding /Users/dhs/documents/fluttersdk/flutter/bin to the front
      of your path.
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 55c988fb45 (4 hours ago), 2023-04-27 20:32:55 -0400
    • Engine revision 1d25906b4c
    • Dart version 3.1.0 (build 3.1.0-49.0.dev)
    • DevTools version 2.23.1
    • If those were intentional, you can disregard the above warnings; however
      it is recommended to use "git" directly to perform update checks and
      upgrades.

[!] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
    • Android SDK at /Users/dhs/Library/Android/sdk
    ✗ cmdline-tools component is missing
      Run `path/to/sdkmanager --install "cmdline-tools;latest"`
      See https://developer.android.com/studio/command-line for more details.
    ✗ Android license status unknown.
      Run `flutter doctor --android-licenses` to accept the SDK licenses.
      See https://flutter.dev/docs/get-started/install/macos#android-setup for
      more details.

[✓] Xcode - develop for iOS and macOS (Xcode 13.2.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 13C100
    • CocoaPods version 1.11.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] IntelliJ IDEA Ultimate Edition (version 2021.3.2)
    • IntelliJ at /Applications/IntelliJ IDEA.app
    • Flutter plugin version 65.1.4
    • Dart plugin version 213.7228

[✓] VS Code (version 1.62.0)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.29.0

[✓] Connected device (3 available)
    • Darshan's iphone (mobile) • 21150b119064aecc249dfcfe05e259197461ce23 • ios
      • iOS 15.3.1 19D52
    • macOS (desktop)           • macos                                    •
      darwin-x64     • macOS 12.2.1 21D62 darwin-x64
    • Chrome (web)              • chrome                                   •
      web-javascript • Google Chrome 109.0.5414.119

[✓] Network resources
    • All expected network resources are available.

! Doctor found issues in 1 category.
      
[!] Xcode - develop for iOS and macOS (Xcode 12.3)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    ! Flutter recommends a minimum Xcode version of 13.
      Download the latest version or update via the Mac App Store.
    • CocoaPods version 1.11.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] VS Code (version 1.62.0)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.21.0

[✓] Connected device (5 available)
    • SM G975F (mobile)       • RZ8M802WY0X • android-arm64   • Android 11 (API 30)
    • Darshan's iphone (mobile)  • 21150b119064aecc249dfcfe05e259197461ce23 •
      ios            • iOS 14.4.1 18D61
    • iPhone 12 Pro Max (mobile) • A5473606-0213-4FD8-BA16-553433949729     •
      ios            • com.apple.CoreSimulator.SimRuntime.iOS-14-3 (simulator)
    • macOS (desktop)            • macos                                    •
      darwin-x64     • Mac OS X 10.15.4 19E2269 darwin-x64
    • Chrome (web)               • chrome                                   •
      web-javascript • Google Chrome 98.0.4758.80

[✓] HTTP Host Availability
    • All required HTTP hosts are available

! Doctor found issues in 1 category.