From d73dd6b3560620109dfb094505bb63de53471b80 Mon Sep 17 00:00:00 2001
From: Zachary Anderson <zanderso@users.noreply.github.com>
Date: Tue, 25 Feb 2020 15:22:17 -0500
Subject: [PATCH] [flutter_tools] Rework iOS vmservice handshake failure usage
 event (#51419)

---
 .../lib/src/ios/fallback_discovery.dart       | 37 ++++++++++++-------
 .../test/general.shard/ios/devices_test.dart  |  2 +-
 2 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/packages/flutter_tools/lib/src/ios/fallback_discovery.dart b/packages/flutter_tools/lib/src/ios/fallback_discovery.dart
index cf8883f8bdc..12d9f2d188e 100644
--- a/packages/flutter_tools/lib/src/ios/fallback_discovery.dart
+++ b/packages/flutter_tools/lib/src/ios/fallback_discovery.dart
@@ -6,6 +6,7 @@ import 'package:meta/meta.dart';
 import 'package:vm_service/vm_service.dart';
 import 'package:vm_service/vm_service_io.dart' as vm_service_io;
 
+import '../base/io.dart';
 import '../base/logger.dart';
 import '../device.dart';
 import '../mdns_discovery.dart';
@@ -120,19 +121,14 @@ class FallbackDiscovery {
     } on Exception catch (err) {
       _logger.printTrace(err.toString());
       _logger.printTrace('Failed to connect directly, falling back to mDNS');
-      UsageEvent(
-        _kEventName,
-        'failure',
-        label: err.toString(),
-        value: hostPort,
-      ).send();
+      _sendFailureEvent(err, assumedDevicePort);
       return null;
     }
 
     // Attempt to connect to the VM service 5 times.
     int attempts = 0;
     const int kDelaySeconds = 2;
-    Object firstException;
+    Exception firstException;
     while (attempts < 5) {
       try {
         final VmService vmService = await _vmServiceConnectUri(assumedWsUri.toString());
@@ -163,12 +159,27 @@ class FallbackDiscovery {
       attempts += 1;
     }
     _logger.printTrace('Failed to connect directly, falling back to mDNS');
-    UsageEvent(
-      _kEventName,
-      'failure',
-      label: firstException?.toString() ?? 'Connection attempts exhausted',
-      value: hostPort,
-    ).send();
+    _sendFailureEvent(firstException, assumedDevicePort);
     return null;
   }
+
+  void _sendFailureEvent(Exception err, int assumedDevicePort) {
+    String eventAction;
+    String eventLabel;
+    if (err == null) {
+      eventAction = 'failure-attempts-exhausted';
+      eventLabel = assumedDevicePort.toString();
+    } else if (err is HttpException) {
+      eventAction = 'failure-http';
+      eventLabel = '${err.message}, device port = $assumedDevicePort';
+    } else {
+      eventAction = 'failure-other';
+      eventLabel = '$err, device port = $assumedDevicePort';
+    }
+    UsageEvent(
+      _kEventName,
+      eventAction,
+      label: eventLabel,
+    ).send();
+  }
 }
diff --git a/packages/flutter_tools/test/general.shard/ios/devices_test.dart b/packages/flutter_tools/test/general.shard/ios/devices_test.dart
index 6ec864d2d31..1daacc484c2 100644
--- a/packages/flutter_tools/test/general.shard/ios/devices_test.dart
+++ b/packages/flutter_tools/test/general.shard/ios/devices_test.dart
@@ -643,7 +643,7 @@ void main() {
         expect(launchResult.hasObservatory, isFalse);
         verify(mockUsage.sendEvent(
           'ios-handshake',
-          'failure',
+          'failure-other',
           label: anyNamed('label'),
           value: anyNamed('value'),
         )).called(1);