TF-1018 Add abstract Config loader and parser

core/lib/core.dart

@@ -36,6 +36,9 @@ export 'utils/benchmark.dart';
 export 'utils/fps_manager.dart';
 export 'utils/build_utils.dart';
 export 'utils/string_convert.dart';
+export 'utils/config/app_config_loader.dart';
+export 'utils/config/app_config_parser.dart';
+export 'utils/config/errors.dart';
 export 'data/utils/compress_file_utils.dart';
 
 // Views

core/lib/utils/config/app_config_loader.dart

@@ -0,0 +1,34 @@
+import 'package:core/utils/config/app_config_parser.dart';
+import 'package:core/utils/config/errors.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter/services.dart' show rootBundle;
+
+class AppConfigLoader {
+  Future<T> load<T>(String fileName, AppConfigParser parser) async {
+    try {
+      WidgetsFlutterBinding.ensureInitialized();
+      var envString = await rootBundle.loadString(fileName);
+      if (envString.isEmpty) {
+        throw EmptyConfiguration();
+      }
+
+      return await parser.parse(envString);
+    } on FlutterError {
+      throw ConfigurationNotFoundError();
+    }
+  }
+
+  Future<T> loadData<T>(String fileName, AppConfigParser parser) async {
+    try {
+      WidgetsFlutterBinding.ensureInitialized();
+      var envData = await rootBundle.load(fileName);
+      if (envData.lengthInBytes == 0) {
+        throw EmptyConfiguration();
+      }
+
+      return await parser.parseData(envData);
+    } on FlutterError {
+      throw ConfigurationNotFoundError();
+    }
+  }
+}

core/lib/utils/config/app_config_parser.dart

@@ -0,0 +1,8 @@
+import 'dart:async';
+
+import 'package:flutter/services.dart';
+
+abstract class AppConfigParser<T> {
+  Future<T> parse(String value);
+  Future<T> parseData(ByteData data);
+}

core/lib/utils/config/errors.dart

@@ -0,0 +1,7 @@
+class NotInitializedError implements Exception {}
+
+class ConfigurationNotFoundError implements Exception {}
+
+class EmptyConfiguration implements Exception {}
+
+class InvalidConfigurationParser implements Exception {}