sentry diagnostics

lib/main.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:aitrainer_app/view/account.dart';
 import 'package:aitrainer_app/view/customer_bodytype_page.dart';
 import 'package:aitrainer_app/view/customer_fitness_page.dart';
@@ -25,8 +27,73 @@ import 'package:flutter/widgets.dart';
 import 'package:provider/provider.dart';
 import 'package:flutter_localizations/flutter_localizations.dart';
 import 'package:aitrainer_app/localization/app_localization.dart';
+import 'package:sentry/sentry.dart';
 
-void main() {
+final SentryClient _sentry = new SentryClient(dsn: 'https://5fac40cbfcfb4c15aa80c7a8638d7310@o418565.ingest.sentry.io/5322520');
+
+/// Whether the VM is running in debug mode.
+///
+/// This is useful to decide whether a report should be sent to sentry. Usually
+/// reports from dev mode are not very useful, as these happen on developers'
+/// workspaces rather than on users' devices in production.
+bool get isInDebugMode {
+  bool inDebugMode = false;
+  assert(inDebugMode = true);
+  return inDebugMode;
+}
+
+/// Reports [error] along with its [stackTrace] to Sentry.io.
+Future<Null> _reportError(dynamic error, dynamic stackTrace) async {
+  print('Caught error: $error');
+
+  // Errors thrown in development mode are unlikely to be interesting. You can
+  // check if you are running in dev mode using an assertion and omit sending
+  // the report.
+  if (isInDebugMode) {
+    print(stackTrace);
+    print('In dev mode. Not sending report to Sentry.io.');
+    return;
+  }
+
+  print('Reporting to Sentry.io...');
+
+  final SentryResponse response = await _sentry.captureException(
+    exception: error,
+    stackTrace: stackTrace,
+  );
+
+  if (response.isSuccessful) {
+    print('Success! Event ID: ${response.eventId}');
+  } else {
+    print('Failed to report to Sentry.io: ${response.error}');
+  }
+}
+
+Future<Null> main() async {
+  // This captures errors reported by the Flutter framework.
+  FlutterError.onError = (FlutterErrorDetails details) async {
+    if (isInDebugMode) {
+      // In development mode simply print to console.
+      FlutterError.dumpErrorToConsole(details);
+    } else {
+      // In production mode report to the application zone to report to
+      // Sentry.
+      Zone.current.handleUncaughtError(details.exception, details.stack);
+    }
+  };
+
+  // This creates a [Zone] that contains the Flutter application and stablishes
+  // an error handler that captures errors and reports them.
+  //
+  // Using a zone makes sure that as many errors as possible are captured,
+  // including those thrown from [Timer]s, microtasks, I/O, and those forwarded
+  // from the `FlutterError` handler.
+  //
+  // More about zones:
+  //
+  // - https://api.dartlang.org/stable/1.24.2/dart-async/Zone-class.html
+  // - https://www.dartlang.org/articles/libraries/zones
+  runZonedGuarded<Future<Null>>(() async {
     runApp(
         MultiProvider(
           // Initialize the model in the builder. That way, Provider
@@ -38,10 +105,13 @@ void main() {
           ],
 
           child: AitrainerApp(),
-      ),
-  );
+        ));
+  }, (error, stackTrace) async {
+    await _reportError(error, stackTrace);
+  });
 }
 
+
 class AitrainerApp extends StatelessWidget {
 
   @override

lib/widgets/bottom_nav.dart

@@ -40,6 +40,10 @@ class BottomNavigator {
                 Navigator.of(context).pop();
                 Navigator.of(context).pushNamed('home');
 
+                break;
+              case 1:
+                throw new StateError('This is a Dart exception on event.');
+
                 break;
               case 2:
                 Navigator.of(context).pop();