New event added for sending analytics within package on errors (#229)

* Added new event + refactoring sentEvent on impl

* Fix tests + limiting one error event for logFileStats

* Make `Analytics` required for `LogHandler`

* Make error sent a field in class

* Events added for error handling in session handler

* Remove unnecessary `io` import

* Refactoring `legacyOptOut` to use loop

* Only expose `sentEvents` on the  `FakeAnalytics` instance

* Bump version

* Misc

* Convert to wip

* Pass send method instead of `Analytics` + nits

* `ErrorHandler` class created + used in session

* Use `ErrorHandler` with `LogHandler`

* Check telemetry status in `Session`

* Tests added for the survey handler

* Fix error

* Tests added for log handler exceptions

* Use set for sent error messages

* Test added to check for 2 unique error events

pkgs/unified_analytics/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 5.8.2-wip
+
+- Added new event `Event.analyticsException` to track internal errors for this package
+- Redirecting the `Analytics.test` factory to return an instance of `FakeAnalytics`
+
 ## 5.8.1
 
 - Refactor logic for `okToSend` and `shouldShowMessage`

pkgs/unified_analytics/lib/src/analytics.dart

@@ -16,6 +16,7 @@ import 'asserts.dart';
 import 'config_handler.dart';
 import 'constants.dart';
 import 'enums.dart';
+import 'error_handler.dart';
 import 'event.dart';
 import 'ga_client.dart';
 import 'initializer.dart';
@@ -25,6 +26,9 @@ import 'survey_handler.dart';
 import 'user_property.dart';
 import 'utils.dart';
 
+/// For passing the [Analytics.send] method to classes created by [Analytics].
+typedef SendFunction = void Function(Event event);
+
 abstract class Analytics {
   /// The default factory constructor that will return an implementation
   /// of the [Analytics] abstract class using the [LocalFileSystem].
@@ -60,7 +64,7 @@ abstract class Analytics {
     final homeDirectory = getHomeDirectory(fs);
     if (homeDirectory == null ||
         !checkDirectoryForWritePermissions(homeDirectory)) {
-      return NoOpAnalytics();
+      return const NoOpAnalytics();
     }
 
     // Resolve the OS using dart:io
@@ -187,7 +191,7 @@ abstract class Analytics {
     int toolsMessageVersion = kToolsMessageVersion,
     String toolsMessage = kToolsMessage,
   }) =>
-      AnalyticsImpl(
+      FakeAnalytics(
         tool: tool,
         homeDirectory: homeDirectory,
         flutterChannel: flutterChannel,
@@ -203,7 +207,6 @@ abstract class Analytics {
               initializedSurveys: [],
             ),
         gaClient: gaClient ?? const FakeGAClient(),
-        enableAsserts: true,
         clientIde: clientIde,
         enabledFeatures: enabledFeatures,
       );
@@ -325,6 +328,7 @@ class AnalyticsImpl implements Analytics {
   late final UserProperty userProperty;
   late final LogHandler _logHandler;
   late final Session _sessionHandler;
+  late final ErrorHandler _errorHandler;
   final int toolsMessageVersion;
 
   /// Tells the client if they need to show a message to the
@@ -414,11 +418,20 @@ class AnalyticsImpl implements Analytics {
         p.join(homeDirectory.path, kDartToolDirectoryName, kClientIdFileName));
     _clientId = _clientIdFile.readAsStringSync();
 
+    // Initialization for the error handling class that will prevent duplicate
+    // [Event.analyticsException] events from being sent to GA4
+    _errorHandler = ErrorHandler(sendFunction: send);
+
     // Initialize the user property class that will be attached to
     // each event that is sent to Google Analytics -- it will be responsible
     // for getting the session id or rolling the session if the duration
     // exceeds [kSessionDurationMinutes]
-    _sessionHandler = Session(homeDirectory: homeDirectory, fs: fs);
+    _sessionHandler = Session(
+      homeDirectory: homeDirectory,
+      fs: fs,
+      errorHandler: _errorHandler,
+      telemetryEnabled: telemetryEnabled,
+    );
     userProperty = UserProperty(
       session: _sessionHandler,
       flutterChannel: flutterChannel,
@@ -436,7 +449,11 @@ class AnalyticsImpl implements Analytics {
     );
 
     // Initialize the log handler to persist events that are being sent
-    _logHandler = LogHandler(fs: fs, homeDirectory: homeDirectory);
+    _logHandler = LogHandler(
+      fs: fs,
+      homeDirectory: homeDirectory,
+      errorHandler: _errorHandler,
+    );
   }
 
   @override
@@ -712,10 +729,12 @@ class FakeAnalytics extends AnalyticsImpl {
     super.flutterVersion,
     super.clientIde,
     super.enabledFeatures,
+    int? toolsMessageVersion,
+    GAClient? gaClient,
   }) : super(
-          gaClient: const FakeGAClient(),
+          gaClient: gaClient ?? const FakeGAClient(),
           enableAsserts: true,
-          toolsMessageVersion: kToolsMessageVersion,
+          toolsMessageVersion: toolsMessageVersion ?? kToolsMessageVersion,
         );
 
   @override
@@ -767,9 +786,7 @@ class NoOpAnalytics implements Analytics {
   final Map<String, Map<String, Object?>> userPropertyMap =
       const <String, Map<String, Object?>>{};
 
-  factory NoOpAnalytics() => const NoOpAnalytics._();
-
-  const NoOpAnalytics._();
+  const NoOpAnalytics();
 
   @override
   String get clientId => staticClientId;

pkgs/unified_analytics/lib/src/constants.dart

@@ -82,7 +82,7 @@ const int kLogFileLength = 2500;
 const String kLogFileName = 'dart-flutter-telemetry.log';
 
 /// The current version of the package, should be in line with pubspec version.
-const String kPackageVersion = '5.8.1';
+const String kPackageVersion = '5.8.2-wip';
 
 /// The minimum length for a session.
 const int kSessionDurationMinutes = 30;

pkgs/unified_analytics/lib/src/enums.dart

@@ -22,6 +22,10 @@ enum DashEvent {
     label: 'analytics_collection_enabled',
     description: 'The opt-in status for analytics collection',
   ),
+  analyticsException(
+    label: 'analytics_exception',
+    description: 'Errors that are encountered within package:unified_analytics',
+  ),
   exception(
     label: 'exception',
     description: 'General errors to log',

pkgs/unified_analytics/lib/src/error_handler.dart

@@ -0,0 +1,32 @@
+// Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'analytics.dart';
+import 'enums.dart';
+import 'event.dart';
+
+class ErrorHandler {
+  /// Stores each of the events that have been sent to GA4 so that the
+  /// same error doesn't get sent twice.
+  final Set<Event> _sentErrorEvents = {};
+  final SendFunction _sendFunction;
+
+  /// Handles any errors encountered within package:unified_analytics.
+  ErrorHandler({required SendFunction sendFunction})
+      : _sendFunction = sendFunction;
+
+  /// Sends the encountered error [Event.analyticsException] to GA4 backend.
+  ///
+  /// This method will not send the event to GA4 if it has already been
+  /// sent before during the current process.
+  void log(Event event) {
+    if (event.eventName != DashEvent.analyticsException ||
+        _sentErrorEvents.contains(event)) {
+      return;
+    }
+
+    _sendFunction(event);
+    _sentErrorEvents.add(event);
+  }
+}

pkgs/unified_analytics/lib/src/event.dart

@@ -19,6 +19,30 @@ final class Event {
       : eventName = DashEvent.analyticsCollectionEnabled,
         eventData = {'status': status};
 
+  /// Event that is emitted when an error occurs within
+  /// `package:unified_analytics`, tools that are using this package
+  /// should not use this event constructor.
+  ///
+  /// Tools using this package should instead use the more generic
+  /// [Event.exception] constructor.
+  ///
+  /// [workflow] - refers to what process caused the error, such as
+  ///   "LogHandler.logFileStats".
+  ///
+  /// [error] - the name of the error, such as "FormatException".
+  ///
+  /// [description] - the description of the error being caught.
+  Event.analyticsException({
+    required String workflow,
+    required String error,
+    String? description,
+  })  : eventName = DashEvent.analyticsException,
+        eventData = {
+          'workflow': workflow,
+          'error': error,
+          if (description != null) 'description': description,
+        };
+
   /// This is for various workflows within the flutter tool related
   /// to iOS and macOS workflows.
   ///
@@ -685,7 +709,7 @@ final class Event {
         };
 
   @override
-  int get hashCode => eventData.hashCode;
+  int get hashCode => Object.hash(eventName, jsonEncode(eventData));
 
   @override
   bool operator ==(Object other) =>