Flutter Crash Reporting and Error Tracking

Docs > RUM & Session Replay > Error Tracking for Web and Mobile Applications > Mobile Crash Reporting > Flutter Crash Reporting and Error Tracking

Overview

Enable Crash Reporting and Error Tracking to get comprehensive crash reports and error trends with Real User Monitoring.

Your crash reports appear in Error Tracking.

Setup

If you have not set up the Datadog Flutter SDK for RUM yet, follow the in-app setup instructions or see the Flutter setup documentation.

Add Dart error tracking

If you are using DatadogSdk.runApp, then the Datadog Flutter SDK automatically tracks and reports uncaught Dart exceptions.

If you are not using DatadogSdk.runApp, you need to setup Dart error tracking manually with the following code before you initialize Datadog:

final originalOnError = FlutterError.onError;
FlutterError.onError = (details) {
  DatadogSdk.instance.rum?.handleFlutterError(details);
  originalOnError?.call(details);
};
final platformOriginalOnError = PlatformDispatcher.instance.onError;
PlatformDispatcher.instance.onError = (e, st) {
  DatadogSdk.instance.rum?.addErrorInfo(
    e.toString(),
    RumErrorSource.source,
    stackTrace: st,
  );
  return platformOriginalOnError?.call(e, st) ?? false;
};

Add native crash reporting

Update your initialization snippet to enable native crash reporting for iOS and Android by setting nativeCrashReportEnabled to true.

For example:

final configuration = DatadogConfiguration(
  clientToken: '<DD_CLIENT_TOKEN>'
  env: '<DD_ENV>'
  site: DatadogSite.us1,
  nativeCrashReportEnabled: true, // Set this flag
  loggingConfiguration: DatadogLoggingConfiguration(),
  rumConfiguration: DatadogRumConfiguration(
    applicationId: '<DD_APP_ID>',
  ),
);

If your application suffers a fatal crash, the Datadog Flutter SDK uploads a crash report to Datadog after your application restarts. For non-fatal errors, the Datadog Flutter SDK uploads these errors with other RUM data.

Get deobfuscated stack traces

Mapping files are used to deobfuscate stack traces, which helps in debugging errors. Using a unique build ID that gets generated, Datadog automatically matches the correct stack traces with the corresponding mapping files. This ensures that regardless of when the mapping file was uploaded (either during pre-production or production builds), the correct information is available for efficient QA processes when reviewing crashes and errors reported in Datadog.

For Flutter applications, the matching of stack traces and source maps relies on their service, version, variant, and architecture fields.

Upload symbol files to Datadog

Native iOS crash reports are collected in a raw format and mostly contain memory addresses. To map these addresses into legible symbol information, Datadog requires that you upload .dSYM files, which are generated in your application’s build process.

Crash reports and errors sent from Flutter iOS and Android applications that are built with the --split-debug-info option set and/or with the --obfuscate option set will also be in a raw or obfuscated format. For these applications, you need to upload their Android Proguard mapping file and Dart symbol files generated by the Flutter build process.

Errors sent from Flutter Web applications will send unmapped JavaScript file and line numbers, which need to be mapped to Dart file and line numbers. For these applications, you need to upload the Flutter generated JavaScript source map generated by the Flutter build porcess.

The @datadog/datadog-ci command line tool supports uploading all of the necessary files (dSYMs, Android Proguard Mapping, and Dart Symbol Files) in one command.

First, install the datadog-ci tool from the instructions above and create a datadog-ci.json file at the root of your project, containing your API key and (optionally) your Datadog site:

{
  "apiKey": "<YOUR_DATADOG_API_KEY>",
  "datadogSite": "datadoghq.eu"  // Optional if you are using datadoghq.com
}

Because this file contains your API key, it should not be checked in to version control.

Alternately, you can set the DATADOG_API_KEY and DATADOG_SITE environment variables.

Then, you can use the following command to upload all the necessary files for symbolication and deobfuscation of your crash reports:

datadog-ci flutter-symbols upload --service-name <your_service_name> --dart-symbols-location <location_of_dart_symbols> --android-mapping --ios-dsyms

Note: Re-uploading a source map does not override the existing one if the version has not changed.

For a full list of options, see the datadog-ci Flutter Symbols documentation.

Limitations

Test your implementation

To verify your Flutter Crash Reporting and Error Tracking configuration, issue an error in your RUM application and confirm that the error appears in Datadog.

Run your application on a simulator, emulator, or a real device. If you are running on iOS, ensure that the debugger is not attached. Otherwise, Xcode captures the crash before the Datadog SDK does.

Execute code containing an error or crash. For example:

void throwError() {
 throw Exception("My Exception")
}

For obfuscated error reports that do not result in a crash, you can verify symbolication and deobfuscation in Error Tracking.
For crashes, after the crash happens, restart your application and wait for the Flutter SDK to upload the crash report in Error Tracking.

Flavors and build numbers

Datadog uses the combination of the service-name, version, and flavor to locate the correct symbols for deobfuscation. For your crash reports to have complete information, the parameters sent to the datadog-ci command and the parameters set in DatadogConfiguration must match exactly.

If you are using app flavors in Flutter, you need to set the name of the flavor in DatadogConfiguration.flavor since we cannot detect the flavor automatically. You can then pass this to the --flavor parameter of the datadog-ci command:

datadog-ci flutter-symbols upload --service-name <your_service_name> --dart-symbols-location <location_of_dart_symbols> --android-mapping --ios-dsyms --flavor my_flavor

The Datadog SDK automatically detects the version number of your application specified in your pubspec.yaml up to but not including the build number. If you are using build numbers as part of the version in your application and need to upload symbols for each build, you need to add the version to DatadogConfiguration.version. You can then pass this to the --version parameter of the datadog-ci command:

datadog-ci flutter-symbols upload --service-name <your_service_name> --dart-symbols-location <location_of_dart_symbols> --android-mapping --ios-dsyms --version 1.2.3+22

Note: Datadog uses tags for versions which do not allow +. All tooling automatically replaces + with - so that the version tags are searchable in Datadog.