♻️ refactor: GitHub例外をNetwork例外に変更してドメイン層で定義するように変更

Issue #145

lib/infrastructure/github/exception.dart → lib/domain/exceptions.dart

@@ -2,67 +2,100 @@
 // Use of this source code is governed by a MIT license that can be
 // found in the LICENSE file.
 
-import 'package:flutter/material.dart';
+/// 基底ドメイン例外
+///
+/// ドメイン層が定義する例外の基底クラス
+abstract class DomainException implements Exception {
+  const DomainException(this.message);
 
-/// GitHub API の例外
-class GitHubException implements Exception {
-  const GitHubException([
-    this.message,
+  final Object message;
+}
+
+/// ドメイン層で発生する入力値検査例外
+class ValidatorException extends DomainException {
+  const ValidatorException([
+    super.message = 'validator exception',
+    this.errorMessages = const [],
+  ]);
+
+  /// ユーザーに表示するエラーメッセージのリスト
+  final List<String> errorMessages;
+
+  @override
+  String toString() {
+    return '''
+ValidatorException: $message
+
+Error messages:
+$errorMessages
+''';
+  }
+
+  /// エラーメッセージを返す
+  String get errorMessage => errorMessages.join('\n');
+}
+
+/// インフラストラクチャ層で発生するネットワーク関連の例外
+///
+/// リポジトリ実装がこの例外を投げたら、プレゼンテーション層
+/// で受け取って適切に表示すること。
+class NetworkException extends DomainException {
+  const NetworkException._([
+    super.message = 'network exception',
     String? code,
-    // ignore: unnecessary_this
-  ]) : this.code = code ?? codeUnknown;
+  ]) : code = code ?? codeUnknown;
 
   /// 1. 無効なJSONを送信すると、`400 Bad Request` レスポンスが返されます。
   /// 2. 間違ったタイプの JSON 値を送信すると、`400 Bad Request` レスポンスが返されます。
-  factory GitHubException.badRequest() => const GitHubException(
+  factory NetworkException.badRequest() => const NetworkException._(
         'Illegal request sent. (400)',
         codeBadRequest,
       );
 
   /// 無効な認証情報で認証すると、`401 Unauthorized` が返されます。
-  factory GitHubException.badCredentials() => const GitHubException(
+  factory NetworkException.badCredentials() => const NetworkException._(
         'Illegal request sent. (401)',
         codeBadCredentials,
       );
 
   /// API は、無効な認証情報を含むリクエストを短期間に複数回検出すると、`403 Forbidden` で、
   /// そのユーザに対するすべての認証試行（有効な認証情報を含む）を一時的に拒否します。
-  factory GitHubException.maximumNumberOfLoginAttemptsExceeded() =>
-      const GitHubException(
+  factory NetworkException.maximumNumberOfLoginAttemptsExceeded() =>
+      const NetworkException._(
         'Please wait a while and try again. (403)',
         codeMaximumNumberOfLoginAttemptsExceeded,
       );
 
   /// `404 Not Found`
-  factory GitHubException.notFound() => const GitHubException(
+  factory NetworkException.notFound() => const NetworkException._(
         'No data found. (404)',
         codeNotFound,
       );
 
   /// 無効なフィールドを送信すると、`422 Unprocessable Entity` レスポンスが返されます。
-  factory GitHubException.validationFailed() => const GitHubException(
+  factory NetworkException.validationFailed() => const NetworkException._(
         'Illegal request sent. (422)',
         codeValidationFailed,
       );
 
   /// `503 Service Unavailable` サービス停止中
-  factory GitHubException.serviceUnavailable() => const GitHubException(
+  factory NetworkException.serviceUnavailable() => const NetworkException._(
         'Please wait a while and try again.  (503)',
         codeServiceUnavailable,
       );
 
-  /// 不明なエラー
-  factory GitHubException.unknown() => const GitHubException(
-        'An unknown error has occurred. (-1)',
-        codeUnknown,
-      );
-
   /// インターネット接続不可
-  factory GitHubException.noInternetConnection() => const GitHubException(
+  factory NetworkException.noInternetConnection() => const NetworkException._(
         'Please try again in a good communication environment. (-2)',
         codeNoInternetConnection,
       );
 
+  /// 不明なエラー
+  factory NetworkException.unknown() => const NetworkException._(
+        'An unknown error has occurred. (-1)',
+        codeUnknown,
+      );
+
   // エラーコードの定義
   static const codeBadRequest = 'bad-request';
   static const codeBadCredentials = 'bad-credentials';
@@ -71,35 +104,12 @@ class GitHubException implements Exception {
   static const codeNotFound = 'not-found';
   static const codeValidationFailed = 'validation-failed';
   static const codeServiceUnavailable = 'service-unavailable';
-  static const codeUnknown = 'unknown';
   static const codeNoInternetConnection = 'no-internet-connection';
-
-  /// メッセージ
-  final dynamic message;
+  static const codeUnknown = 'unknown';
 
   /// エラーコード
   final String code;
 
   @override
-  bool operator ==(Object other) {
-    if (identical(this, other)) {
-      return true;
-    }
-    if (other is! GitHubException) {
-      return false;
-    }
-    return other.hashCode == hashCode;
-  }
-
-  @override
-  int get hashCode => hashValues(code, message);
-
-  @override
-  String toString() {
-    final Object? message = this.message;
-    if (message == null) {
-      return 'GitHubException[$code]';
-    }
-    return 'GitHubException[$code]: $message';
-  }
+  String toString() => 'NetworkException[$code]: $message';
 }

lib/infrastructure/github/http_client.dart

@@ -10,8 +10,8 @@ import 'package:http/http.dart' as http;
 
 import '../../config/env.dart';
 import '../../config/env_define.dart';
+import '../../domain/exceptions.dart';
 import '../../utils/logger.dart';
-import 'exception.dart';
 
 /// GitHubアクセストークンプロバイダー
 final githubAccessTokenProvider = Provider<String>(
@@ -75,23 +75,23 @@ class GitHubHttpClient {
           final data = json.decode(response.body) as Map<String, dynamic>;
           return responseBuilder(data);
         case 400:
-          throw GitHubException.badRequest();
+          throw NetworkException.badRequest();
         case 401:
-          throw GitHubException.badCredentials();
+          throw NetworkException.badCredentials();
         case 403:
-          throw GitHubException.maximumNumberOfLoginAttemptsExceeded();
+          throw NetworkException.maximumNumberOfLoginAttemptsExceeded();
         case 404:
-          throw GitHubException.notFound();
+          throw NetworkException.notFound();
         case 422:
-          throw GitHubException.validationFailed();
+          throw NetworkException.validationFailed();
         case 503:
-          throw GitHubException.serviceUnavailable();
+          throw NetworkException.serviceUnavailable();
         default:
-          throw GitHubException.unknown();
+          throw NetworkException.unknown();
       }
     } on SocketException catch (e) {
       logger.w(e);
-      throw GitHubException.noInternetConnection();
+      throw NetworkException.noInternetConnection();
     }
   }
 
@@ -110,17 +110,17 @@ class GitHubHttpClient {
         case 200:
           return response.body;
         case 400:
-          throw GitHubException.badRequest();
+          throw NetworkException.badRequest();
         case 404:
-          throw GitHubException.notFound();
+          throw NetworkException.notFound();
         case 503:
-          throw GitHubException.serviceUnavailable();
+          throw NetworkException.serviceUnavailable();
         default:
-          throw GitHubException.unknown();
+          throw NetworkException.unknown();
       }
     } on SocketException catch (e) {
       logger.w(e);
-      throw GitHubException.noInternetConnection();
+      throw NetworkException.noInternetConnection();
     }
   }
 }

lib/infrastructure/github/repo_repository.dart

@@ -10,9 +10,9 @@ import '../../domain/entities/search_repos_result.dart';
 import '../../domain/entities/search_repos_sort.dart';
 import '../../domain/entities/values/repo_count.dart';
 import '../../domain/entities/values/repo_language.dart';
+import '../../domain/exceptions.dart';
 import '../../domain/repositories/repo_repository.dart';
 import 'api.dart';
-import 'exception.dart';
 import 'http_client.dart';
 import 'json_object/repo/repo.dart';
 import 'json_object/search_repos_result/search_repos_result.dart';
@@ -120,9 +120,9 @@ class GitHubRepoRepository implements RepoRepository {
       );
       try {
         return await _client.getRaw(uri: uri);
-      } on GitHubException catch (e) {
+      } on NetworkException catch (e) {
         // 404 の場合はファイル名を変えてリトライする
-        if (e.code == GitHubException.codeNotFound) {
+        if (e.code == NetworkException.codeNotFound) {
           continue;
         }
 
@@ -132,6 +132,6 @@ class GitHubRepoRepository implements RepoRepository {
     }
 
     // 最終的に取得できなかったら 404 を返す
-    throw GitHubException.notFound();
+    throw NetworkException.notFound();
   }
 }

lib/localizations/strings.i18n.json

@@ -7,7 +7,9 @@
   "error": "Error",
   "errorOccurred": "An error has occurred",
   "forksCount": "Forks count",
-  "gitHubExceptionMessage": {
+  "helpWantedIssuesCount": "Help wanted @:issuesCount",
+  "issuesCount": "Issues count",
+  "networkExceptionMessage": {
     "badRequest": "Illegal request sent (400)",
     "badCredentials": "Illegal request sent (401)",
     "maximumNumberOfLoginAttemptsExceeded": "Please wait a while and try again (403)",
@@ -17,8 +19,6 @@
     "unknown": "An unknown error has occurred (-1)",
     "noInternetConnection": "Please try again in a good communication environment (-2)"
   },
-  "helpWantedIssuesCount": "Help wanted @:issuesCount",
-  "issuesCount": "Issues count",
   "notFoundRepos": "We couldn't find any repositories",
   "ownerName": "Owner name",
   "projectLanguage": "Project language",

lib/localizations/strings_ja.i18n.json

@@ -7,7 +7,9 @@
   "error": "エラー",
   "errorOccurred": "エラーが発生しました",
   "forksCount": "Fork数",
-  "gitHubExceptionMessage": {
+  "helpWantedIssuesCount": "助けを求めている@:issuesCount",
+  "issuesCount": "Issue数",
+  "networkExceptionMessage": {
     "badRequest": "不正なリクエストが送信されました (400)",
     "badCredentials": "不正なリクエストが送信されました (401)",
     "maximumNumberOfLoginAttemptsExceeded": "しばらく時間をおいてから再度お試しください (403)",
@@ -17,8 +19,6 @@
     "unknown": "不明なエラーが発生しました (-1)",
     "noInternetConnection": "通信環境の良いところで再度お試しください (-2)"
   },
-  "helpWantedIssuesCount": "助けを求めている@:issuesCount",
-  "issuesCount": "Issue数",
   "notFoundRepos": "リポジトリが見つかりませんでした",
   "ownerName": "オーナー名",
   "projectLanguage": "プロジェクト言語",

lib/presentation/common/components/error_view.dart

@@ -5,8 +5,9 @@
 import 'package:flutter/material.dart';
 import 'package:lottie/lottie.dart';
 
+import '../../../domain/exceptions.dart';
+import '../../../localizations/strings.g.dart';
 import '../../../utils/assets/assets.gen.dart';
-import '../../../utils/extensions.dart';
 import '../../../utils/logger.dart';
 
 /// エラーView
@@ -36,7 +37,7 @@ class ErrorView extends StatelessWidget {
           ),
           const SizedBox(height: 8),
           Text(
-            error.toErrorMessage(),
+            error.errorMessage,
             style: Theme.of(context).textTheme.bodyLarge,
           ),
           const SizedBox(height: 40),
@@ -45,3 +46,32 @@ class ErrorView extends StatelessWidget {
     );
   }
 }
+
+extension ObjectHelper on Object {
+  /// エラーメッセージを返す
+  String get errorMessage {
+    if (this is NetworkException) {
+      final error = this as NetworkException;
+      switch (error.code) {
+        case NetworkException.codeBadRequest:
+          return i18n.networkExceptionMessage.badRequest;
+        case NetworkException.codeBadCredentials:
+          return i18n.networkExceptionMessage.badCredentials;
+        case NetworkException.codeMaximumNumberOfLoginAttemptsExceeded:
+          return i18n
+              .networkExceptionMessage.maximumNumberOfLoginAttemptsExceeded;
+        case NetworkException.codeNotFound:
+          return i18n.networkExceptionMessage.notFound;
+        case NetworkException.codeValidationFailed:
+          return i18n.networkExceptionMessage.validationFailed;
+        case NetworkException.codeServiceUnavailable:
+          return i18n.networkExceptionMessage.serviceUnavailable;
+        case NetworkException.codeUnknown:
+          return i18n.networkExceptionMessage.unknown;
+        case NetworkException.codeNoInternetConnection:
+          return i18n.networkExceptionMessage.noInternetConnection;
+      }
+    }
+    return toString();
+  }
+}