Honor legacy opt out status (#80)

* Function added to check dart and flutter legacy analytics files

* Sort members in utils.dart

* Logic updated to change config string if legacy optout

* Update tests for both dart and flutter legacy analytics

* Doc clean up

* On error, assume user has opted out of legacy analytics

* Update CHANGELOG.md

* Alter consent message based on tool using package

* Clean up try blocks

* Update try blocks for add'l exception + ignore lint for http client

* Change home directory location for windows

* Update documentation on http client

Author: eliasyishak

pkgs/unified_analytics/CHANGELOG.md

@@ -1,6 +1,7 @@
 ## 1.1.0
 
 - Added a `okToSend` getter so that clients can easily and accurately check the state of the consent mechanism.
+- Initialize the config file with user opted out if user was opted out in legacy Flutter and Dart analytics
 
 ## 1.0.1
 

pkgs/unified_analytics/analysis_options.yaml

@@ -18,6 +18,7 @@ include: package:lints/recommended.yaml
 linter:
   rules:
     - always_declare_return_types
+    - avoid_catches_without_on_clauses
     - camel_case_types
     - prefer_single_quotes
     - unawaited_futures

pkgs/unified_analytics/lib/src/analytics.dart

@@ -376,8 +376,15 @@ class AnalyticsImpl implements Analytics {
   }
 
   @override
-  String get getConsentMessage =>
-      kToolsMessage.replaceAll('[tool name]', tool.description);
+  String get getConsentMessage {
+    // The command to swap in the consent message
+    final String commandString =
+        tool == DashTool.flutterTool ? 'flutter' : 'dart';
+
+    return kToolsMessage
+        .replaceAll('[tool name]', tool.description)
+        .replaceAll('[dart|flutter]', commandString);
+  }
 
   /// Checking the [telemetryEnabled] boolean reflects what the
   /// config file reflects

pkgs/unified_analytics/lib/src/ga_client.dart

@@ -47,15 +47,28 @@ class GAClient {
 
   /// Receive the payload in Map form and parse
   /// into JSON to send to GA
+  ///
+  /// The [Response] returned from this method can be
+  /// checked to ensure that events have been sent. A response
+  /// status code of `2xx` indicates a successful send event.
+  /// A response status code of `500` indicates an error occured on the send
+  /// can the error message can be found in the [Response.body]
   Future<http.Response> sendData(Map<String, Object?> body) async {
+    final Uri uri = Uri.parse(postUrl);
+
+    /// Using a try catch all since post method can result in several
+    /// errors; clients using this method can check the awaited status
+    /// code to get a specific error message if the status code returned
+    /// is a 500 error status code
     try {
       return await _client.post(
-        Uri.parse(postUrl),
+        uri,
         headers: <String, String>{
           'Content-Type': 'application/json; charset=UTF-8',
         },
         body: jsonEncode(body),
       );
+      // ignore: avoid_catches_without_on_clauses
     } catch (error) {
       return Future<http.Response>.value(http.Response(error.toString(), 500));
     }

pkgs/unified_analytics/lib/src/initializer.dart

@@ -60,7 +60,16 @@ class Initializer {
     required int toolsMessageVersion,
   }) {
     configFile.createSync(recursive: true);
-    configFile.writeAsStringSync(kConfigString);
+
+    // If the user was previously opted out, then we will
+    // replace the line that assumes automatic opt in with
+    // an opt out from the start
+    if (legacyOptOut(fs: fs, home: homeDirectory)) {
+      configFile.writeAsStringSync(
+          kConfigString.replaceAll('reporting=1', 'reporting=0'));
+    } else {
+      configFile.writeAsStringSync(kConfigString);
+    }
   }
 
   /// Creates that log file that will store the record formatted

pkgs/unified_analytics/lib/src/utils.dart

@@ -2,10 +2,12 @@
 // 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 'dart:convert';
 import 'dart:io' as io;
 import 'dart:math' show Random;
 
 import 'package:file/file.dart';
+import 'package:path/path.dart' as p;
 
 import 'enums.dart';
 import 'user_property.dart';
@@ -75,12 +77,88 @@ Directory getHomeDirectory(FileSystem fs) {
   } else if (io.Platform.isLinux) {
     home = envVars['HOME'];
   } else if (io.Platform.isWindows) {
-    home = envVars['UserProfile'];
+    home = envVars['AppData'];
   }
 
   return fs.directory(home!);
 }
 
+/// Returns `true` if user has opted out of legacy analytics in Dart or Flutter
+///
+/// Checks legacy opt-out status for the Flutter
+/// and Dart in the following locations
+///
+/// Dart: `$HOME/.dart/dartdev.json`
+///
+/// Flutter: `$HOME/.flutter`
+bool legacyOptOut({
+  required FileSystem fs,
+  required Directory home,
+}) {
+  final File dartLegacyConfigFile =
+      fs.file(p.join(home.path, '.dart', 'dartdev.json'));
+  final File flutterLegacyConfigFile = fs.file(p.join(home.path, '.flutter'));
+
+  // Example of what the file looks like for dart
+  //
+  // {
+  //   "firstRun": false,
+  //   "enabled": false,  <-- THIS USER HAS OPTED OUT
+  //   "disclosureShown": true,
+  //   "clientId": "52710e60-7c70-4335-b3a4-9d922630f12a"
+  // }
+  if (dartLegacyConfigFile.existsSync()) {
+    try {
+      // Read in the json object into a Map and check for
+      // the enabled key being set to false; this means the user
+      // has opted out of analytics for dart
+      final Map<String, Object?> dartObj =
+          jsonDecode(dartLegacyConfigFile.readAsStringSync());
+      if (dartObj.containsKey('enabled') && dartObj['enabled'] == false) {
+        return true;
+      }
+    } on FormatException {
+      // In the case of an error when parsing the json file, return true
+      // which will result in the user being opted out of unified_analytics
+      //
+      // A corrupted file could mean they opted out previously but for some
+      // reason, the file was written incorrectly
+      return true;
+    } on FileSystemException {
+      return true;
+    }
+  }
+
+  // Example of what the file looks like for flutter
+  //
+  // {
+  //   "firstRun": false,
+  //   "clientId": "4c3a3d1e-e545-47e7-b4f8-10129f6ab169",
+  //   "enabled": false  <-- THIS USER HAS OPTED OUT
+  // }
+  if (flutterLegacyConfigFile.existsSync()) {
+    try {
+      // Same process as above for dart
+      final Map<String, Object?> flutterObj =
+          jsonDecode(dartLegacyConfigFile.readAsStringSync());
+      if (flutterObj.containsKey('enabled') && flutterObj['enabled'] == false) {
+        return true;
+      }
+    } on FormatException {
+      // In the case of an error when parsing the json file, return true
+      // which will result in the user being opted out of unified_analytics
+      //
+      // A corrupted file could mean they opted out previously but for some
+      // reason, the file was written incorrectly
+      return true;
+    } on FileSystemException {
+      return true;
+    }
+  }
+
+  return false;
+}
+
 /// A UUID generator.
 ///
 /// This will generate unique IDs in the format: