From 7e0b073f32fd9604d49a9033f374d1baa410e69f Mon Sep 17 00:00:00 2001
From: Vishesh Handa <me@vhanda.in>
Date: Mon, 30 Mar 2020 11:20:04 +0200
Subject: [PATCH] Move error reporting to its own file

* Avoid passing Flutter errors to its Zone handler, this doesn't always
catch the errors

* Catch the current isolate's errors. I haven't been able to test this
out, but lets see.
---
 lib/error_reporting.dart | 115 +++++++++++++++++++++++++++++++++++++++
 lib/main.dart            |  39 ++++---------
 2 files changed, 126 insertions(+), 28 deletions(-)
 create mode 100644 lib/error_reporting.dart

diff --git a/lib/error_reporting.dart b/lib/error_reporting.dart
new file mode 100644
index 00000000..191e7af4
--- /dev/null
+++ b/lib/error_reporting.dart
@@ -0,0 +1,115 @@
+import 'dart:async';
+import 'dart:io';
+
+import 'package:device_info/device_info.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter_crashlytics/flutter_crashlytics.dart';
+import 'package:gitjournal/app.dart';
+import 'package:gitjournal/settings.dart';
+import 'package:package_info/package_info.dart';
+import 'package:sentry/sentry.dart';
+
+SentryClient _sentryClient;
+Future<SentryClient> _initSentry() async {
+  return SentryClient(
+    dsn: 'https://35f34dbec289435fbe16483faacf49a5@sentry.io/5168082',
+    environmentAttributes: await _environmentEvent,
+  );
+}
+
+Future<SentryClient> getSentryClient() async {
+  return _sentryClient ??= await _initSentry();
+}
+
+Future<Event> get _environmentEvent async {
+  final packageInfo = await PackageInfo.fromPlatform();
+  final deviceInfoPlugin = DeviceInfoPlugin();
+  OperatingSystem os;
+  Device device;
+  if (Platform.isAndroid) {
+    final androidInfo = await deviceInfoPlugin.androidInfo;
+    os = OperatingSystem(
+      name: 'android',
+      version: androidInfo.version.release,
+    );
+    device = Device(
+      model: androidInfo.model,
+      manufacturer: androidInfo.manufacturer,
+      modelId: androidInfo.product,
+    );
+  } else if (Platform.isIOS) {
+    final iosInfo = await deviceInfoPlugin.iosInfo;
+    os = OperatingSystem(
+      name: iosInfo.systemName,
+      version: iosInfo.systemVersion,
+    );
+    device = Device(
+      model: iosInfo.utsname.machine,
+      family: iosInfo.model,
+      manufacturer: 'Apple',
+    );
+  }
+  final environment = Event(
+    release: '${packageInfo.version} (${packageInfo.buildNumber})',
+    contexts: Contexts(
+      operatingSystem: os,
+      device: device,
+      app: App(
+        name: packageInfo.appName,
+        version: packageInfo.version,
+        build: packageInfo.buildNumber,
+      ),
+    ),
+  );
+  return environment;
+}
+
+void flutterOnErrorHandler(FlutterErrorDetails details) {
+  if (reportCrashes == true) {
+    // vHanda: This doesn't always call our zone error handler, why?
+    // Zone.current.handleUncaughtError(details.exception, details.stack);
+    reportError(details.exception, details.stack);
+  } else {
+    FlutterError.dumpErrorToConsole(details);
+  }
+}
+
+bool get reportCrashes => _reportCrashes ??= _initReportCrashes();
+bool _reportCrashes;
+bool _initReportCrashes() {
+  return !JournalApp.isInDebugMode && Settings.instance.collectCrashReports;
+}
+
+Future<FlutterCrashlytics> getCrashlyticsClient() async {
+  return _crashlytics ??= await _initCrashlytics();
+}
+
+FlutterCrashlytics _crashlytics;
+Future<FlutterCrashlytics> _initCrashlytics() async {
+  await FlutterCrashlytics().initialize();
+  return FlutterCrashlytics();
+}
+
+Future<void> reportError(Object error, StackTrace stackTrace) async {
+  if (reportCrashes) {
+    try {
+      final sentry = await getSentryClient();
+      sentry.captureException(
+        exception: error,
+        stackTrace: stackTrace,
+      );
+    } catch (e) {
+      print("Failed to report with Sentry: $e");
+    }
+
+    try {
+      final crashlytics = await getCrashlyticsClient();
+      crashlytics.reportCrash(error, stackTrace, forceCrash: false);
+    } catch (e) {
+      print("Failed to report with Crashlytics: $e");
+    }
+  }
+
+  print("Uncaught Exception: $error");
+  print(stackTrace);
+}
diff --git a/lib/main.dart b/lib/main.dart
index bfe208d0..8cd7a045 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -1,10 +1,10 @@
 import 'dart:async';
+import 'dart:isolate';
 
 import 'package:flutter/material.dart';
 import 'package:flutter/foundation.dart' as foundation;
 
-import 'package:flutter_crashlytics/flutter_crashlytics.dart';
-import 'package:sentry/sentry.dart';
+import 'package:gitjournal/error_reporting.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
 import 'package:gitjournal/app.dart';
@@ -17,35 +17,18 @@ void main() async {
   Settings.instance.load(pref);
 
   JournalApp.isInDebugMode = foundation.kDebugMode;
-  var reportCrashes =
-      !JournalApp.isInDebugMode && Settings.instance.collectCrashReports;
+  FlutterError.onError = flutterOnErrorHandler;
 
-  FlutterError.onError = (FlutterErrorDetails details) {
-    if (!reportCrashes) {
-      FlutterError.dumpErrorToConsole(details);
-    } else {
-      Zone.current.handleUncaughtError(details.exception, details.stack);
-    }
-  };
+  Isolate.current.addErrorListener(RawReceivePort((dynamic pair) async {
+    var isolateError = pair as List<dynamic>;
+    assert(isolateError.length == 2);
+    assert(isolateError.first.runtimeType == Error);
+    assert(isolateError.last.runtimeType == StackTrace);
 
-  print("Report Crashes: $reportCrashes");
-  if (reportCrashes) {
-    await FlutterCrashlytics().initialize();
-  }
-
-  var sentry = SentryClient(
-    dsn: 'https://35f34dbec289435fbe16483faacf49a5@sentry.io/5168082',
-  );
+    await reportError(isolateError.first, isolateError.last);
+  }).sendPort);
 
   runZoned<Future<void>>(() async {
     await JournalApp.main(pref);
-  }, onError: (Object error, StackTrace stackTrace) async {
-    print("Uncaught Exception: " + error.toString());
-    print(stackTrace);
-    FlutterCrashlytics().reportCrash(error, stackTrace, forceCrash: false);
-    sentry.captureException(
-      exception: error,
-      stackTrace: stackTrace,
-    );
-  });
+  }, onError: reportError);
 }