Can't return a modified breadcrumb via `beforeBreadcrumb` with `copyWith()`

[jamieastley]

Platform:

• Dart
• Flutter Android or iOS
• Flutter Web

IDE:

• VSCode
• IntelliJ/AS
• XCode
• Other, which one?

split-debug-info and obfuscate (Flutter Android or iOS) or CanvasKit (Flutter Web):

• Enabled
• Disabled

Platform installed with:

• pub.dev
• GitHub

Output of the command flutter doctor -v below:

flutter doctor -v

[✓] Flutter (Channel stable, 3.3.10, on macOS 13.0.1 22A400 darwin-arm, locale en-AU)
    • Flutter version 3.3.10 on channel stable at /path/to/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 135454af32 (2 months ago), 2022-12-15 07:36:55 -0800
    • Engine revision 3316dd8728
    • Dart version 2.18.6
    • DevTools version 2.15.0

[!] Android toolchain - develop for Android devices (Android SDK version 33.0.1)
    • Android SDK at /path/to/Library/Android/sdk
    • Platform android-33, build-tools 33.0.1
    • Java binary at: /Library/Java/JavaVirtualMachines/temurin-8.jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (Temurin)(build 1.8.0_302-b08)
    ✗ 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 14.2)
    • Xcode at /Applications/Xcode-14.2.0.app/Contents/Developer
    • Build 14C18
    • CocoaPods version 1.11.3

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

[!] Android Studio
    • Android Studio at /path/to/Library/Application Support/JetBrains/Toolbox/apps/AndroidStudio/ch-1/222.4459.24.2221.9601061/Android Studio Preview.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
    ✗ Unable to find bundled Java version.
    • Try updating or re-installing Android Studio.

[✓] IntelliJ IDEA Ultimate Edition (version 2022.3.2)
    • IntelliJ at /path/to/Library/Application Support/JetBrains/Toolbox/apps/IDEA-U/ch-0/223.8617.56/IntelliJ IDEA.app
    • 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

[✓] VS Code (version 1.75.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.58.0

[✓] Connected device (3 available)
    • Pixel 2 (mobile) • <device-id> • android-arm64  • Android 11 (API 30)
    • macOS (desktop)  • macos        • darwin-arm64   • macOS 13.0.1 22A400 darwin-arm
    • Chrome (web)     • chrome       • web-javascript • Google Chrome 110.0.5481.100

[!] HTTP Host Availability
    ✗ HTTP host "https://cocoapods.org/" is not reachable. Reason: Failed to connect to host in 10 seconds

! Doctor found issues in 6 categories.

The version of the SDK (See pubspec.lock):
6.20.1

---

I have the following issue:

Potentially related to #982 , manipulating a breadcrumb within beforeBreadcrumb has no effect when copyWith() is used.

In our current project we pass classes as navigation arguments instead of Map<String, dynamic>, and some of these classes contain PII/verbose values which we don't want or need in our breadcrumbs. Since Sentry will invoke toString() on these nav arg models to capture within breadcrumb data, we can't parse this string back to a class to nullify/remove values we don't want sent, and therefor need to manually remove the from_arguments/to_arguments key pairs so can we instead attach our sanitised data to breadcrumbs via the additionalnfoProvider callback of SentryNavigatorObserver.

Directly mutating the breadcrumb itself rather than returning a copy works as intended, however this isn't documented to be expected behaviour, nor does it feel like a good way to achieve this.

Breadcrumb? sanitiseBreadcrumb(Breadcrumb? breadcrumb, {dynamic hint}) {
  breadcrumb?.data?.remove('from_arguments');
  breadcrumb?.data?.remove('to_arguments');
  return breadcrumb;
}

Steps to reproduce:

Breadcrumb? sanitiseBreadcrumb(Breadcrumb? breadcrumb, {dynamic hint}) {
  final sanitisedData = Map<String, dynamic>.from(breadcrumb?.data ?? {})
    ..remove('from_arguments')
    ..remove('to_arguments');

  return breadcrumb?.copyWith(data: sanitisedData);
}

await SentryFlutter.init(
  (options) {
    options

      // DSN setup etc ...

      ..beforeBreadcrumb = sanitiseBreadcrumb;
  },
);

Actual result:

• from_arguments/to_arguments key value pairs are still logged to Sentry.

Expected result:

• from_arguments/to_arguments should be removed from the breadcrumb.

[marandaneto]

@jamieastley Thanks for reporting, I'm gonna take a look.

[marandaneto]

@jamieastley I actually just tested this and

Breadcrumb? sanitiseBreadcrumb(Breadcrumb? breadcrumb, {dynamic hint}) {
  final sanitisedData = Map<String, dynamic>.from(breadcrumb?.data ?? {})
    ..remove('from_arguments')
    ..remove('to_arguments');

  return breadcrumb?.copyWith(data: sanitisedData);
}

works as intended, the data is without the from_arguments and to_arguments.
Filtering docs.
If it does not work for you, can you provide a minimal reproducible example?

[jamieastley]

thanks @marandaneto , will try and provide a reproducible example shortly.

[jamieastley]

@marandaneto here's a reproducible sample app.

to/from args are still captured in Sentry:

[marandaneto]

Ok, I found the reason, thanks for reporting.
The reason is that the crumb is being mutated by the sanitiseBreadcrumb but we are syncing the scope with the non-mutated crumb.

sentry-dart/dart/lib/src/scope.dart

Line 203 in d301b11

await scopeObserver.addBreadcrumb(breadcrumb));

should pass the processedBreadcrumb instead.