[webview_flutter_platform_interface] Adds support to respond to recoverable SSL certificate errors

packages/webview_flutter/webview_flutter_platform_interface/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.13.0
+
+* Adds support to respond to recoverable SSL certificate errors. See `PlatformNavigationDelegate.setOnSSlAuthError`.
+
 ## 2.12.0
 
 * Adds support to set whether to draw the scrollbar. See

packages/webview_flutter/webview_flutter_platform_interface/lib/src/platform_navigation_delegate.dart

@@ -6,6 +6,7 @@ import 'dart:async';
 
 import 'package:flutter/foundation.dart';
 import 'package:plugin_platform_interface/plugin_platform_interface.dart';
+import 'platform_ssl_auth_error.dart';
 import 'types/types.dart';
 
 import 'webview_platform.dart' show WebViewPlatform;
@@ -34,6 +35,13 @@ typedef UrlChangeCallback = void Function(UrlChange change);
 /// authentication request.
 typedef HttpAuthRequestCallback = void Function(HttpAuthRequest request);
 
+/// Signature for callbacks that notify the host application of an SSL
+/// authentication error.
+///
+/// The host application must call either [PlatformSslAuthError.cancel] or
+/// [PlatformSslAuthError.proceed].
+typedef SslAuthErrorCallback = void Function(PlatformSslAuthError error);
+
 /// An interface defining navigation events that occur on the native platform.
 ///
 /// The [PlatformWebViewController] is notifying this delegate on events that
@@ -143,4 +151,15 @@ abstract class PlatformNavigationDelegate extends PlatformInterface {
       'setOnHttpAuthRequest is not implemented on the current platform.',
     );
   }
+
+  /// Invoked when the web view receives a recoverable SSL error for a
+  /// certificate.
+  ///
+  /// The host application must call either [PlatformSslAuthError.cancel] or
+  /// [PlatformSslAuthError.proceed].
+  Future<void> setOnSSlAuthError(SslAuthErrorCallback onSslAuthError) {
+    throw UnimplementedError(
+      'setOnSSlAuthError is not implemented on the current platform.',
+    );
+  }
 }

packages/webview_flutter/webview_flutter_platform_interface/lib/src/platform_ssl_auth_error.dart

@@ -0,0 +1,41 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/foundation.dart';
+
+import 'types/types.dart';
+
+/// Represents an SSL error with the associated certificate.
+///
+/// The host application must call [cancel] or, contrary to secure web
+/// communication standards, [proceed] to provide the web view's response to the
+/// request. [proceed] should generally only be used in test environments, as
+/// using it in production can expose users to security and privacy risks.
+abstract class PlatformSslAuthError {
+  /// Creates a [PlatformSslAuthError].
+  @protected
+  PlatformSslAuthError({required this.certificate, required this.description});
+
+  /// The certificate associated with this error.
+  final X509Certificate? certificate;
+
+  /// A human-presentable description for a given error.
+  final String description;
+
+  /// Instructs the WebView that encountered the SSL certificate error to ignore
+  /// the error and continue communicating with the server.
+  ///
+  /// **Warning:** Warning: Calling [proceed] in a production environment is
+  /// strongly discouraged, as an invalid SSL certificate means that the
+  /// connection is not secure, so proceeding can expose users to security and
+  /// privacy risks.
+  Future<void> proceed();
+
+  /// Instructs the WebView that encountered the SSL certificate error to
+  /// terminate communication with the server.
+  ///
+  /// The host application must call this method to prevent a resource from
+  /// loading when an SSL certificate is invalid.
+  Future<void> cancel();
+}

packages/webview_flutter/webview_flutter_platform_interface/lib/src/types/types.dart

@@ -25,3 +25,4 @@ export 'web_resource_request.dart';
 export 'web_resource_response.dart';
 export 'webview_cookie.dart';
 export 'webview_credential.dart';
+export 'x509_certificate.dart';

packages/webview_flutter/webview_flutter_platform_interface/lib/src/types/x509_certificate.dart

@@ -0,0 +1,15 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/foundation.dart';
+
+/// Represents an X.509 certificate.
+@immutable
+class X509Certificate {
+  /// Creates an [X509Certificate].
+  const X509Certificate({this.data});
+
+  /// A DER representation of the certificate object.
+  final Uint8List? data;
+}

packages/webview_flutter/webview_flutter_platform_interface/lib/webview_flutter_platform_interface.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 export 'src/platform_navigation_delegate.dart';
+export 'src/platform_ssl_auth_error.dart';
 export 'src/platform_webview_controller.dart';
 export 'src/platform_webview_cookie_manager.dart';
 export 'src/platform_webview_widget.dart';

packages/webview_flutter/webview_flutter_platform_interface/pubspec.yaml

@@ -4,7 +4,7 @@ repository: https://github.com/flutter/packages/tree/main/packages/webview_flutt
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+webview_flutter%22
 # NOTE: We strongly prefer non-breaking changes, even at the expense of a
 # less-clean API. See https://flutter.dev/go/platform-interface-breaking-changes
-version: 2.12.0
+version: 2.13.0
 
 environment:
   sdk: ^3.4.0

packages/webview_flutter/webview_flutter_platform_interface/test/platform_navigation_delegate_test.dart

@@ -155,6 +155,19 @@ void main() {
       throwsUnimplementedError,
     );
   });
+
+  test(
+      'Default implementation of setOnSSlAuthError should throw unimplemented error',
+      () {
+    final PlatformNavigationDelegate callbackDelegate =
+        ExtendsPlatformNavigationDelegate(
+            const PlatformNavigationDelegateCreationParams());
+
+    expect(
+      () => callbackDelegate.setOnSSlAuthError((PlatformSslAuthError eror) {}),
+      throwsUnimplementedError,
+    );
+  });
 }
 
 class MockWebViewPlatformWithMixin extends MockWebViewPlatform