WIP

rafamizes · rafamizes · commit eb8004fa8060 · 2024-08-28T19:50:59.000-03:00
diff --git a/lib/src/json_cache.dart b/lib/src/json_cache.dart
@@ -1,3 +1,5 @@
+import 'dart:collection';
+
 /// Represents cached data in json format.
 ///
 ///> Cache is a hardware or software component that stores data so that future
@@ -25,4 +27,9 @@ abstract class JsonCache {
   ///
   /// Returns `true` if there is cached data at [key]; `false` otherwise.
   Future<bool> contains(String key);
+
+  /// Lists all keys.
+  ///
+  /// Returns an **unmodifiable** list of cache keys without duplicates.
+  Future<UnmodifiableListView<String>> keys();
 }
diff --git a/lib/src/json_cache_exception.dart b/lib/src/json_cache_exception.dart
@@ -11,7 +11,7 @@ class JsonCacheException<T extends Object> implements Exception {
 
   /// The original exception that indicated the failure of the caching
   /// operation.
-  final Exception? exception;
+  final Object? exception;
 
   /// Returns [extra] along with the original exception message.
   @override
diff --git a/lib/src/json_cache_fake.dart b/lib/src/json_cache_fake.dart
@@ -1,3 +1,5 @@
+import 'dart:collection';
+
 import 'package:json_cache/json_cache.dart';
 
 /// In-memory cache without synchronization.
@@ -50,4 +52,9 @@ class JsonCacheFake implements JsonCache {
   Future<bool> contains(String key) async {
     return _memory.containsKey(key);
   }
+
+  @override
+  Future<UnmodifiableListView<String>> keys() async {
+    return UnmodifiableListView(_memory.keys);
+  }
 }
diff --git a/lib/src/json_cache_flutter_secure_storage.dart b/lib/src/json_cache_flutter_secure_storage.dart
@@ -1,3 +1,4 @@
+import 'dart:collection';
 import 'dart:convert';
 
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
@@ -39,6 +40,11 @@ class JsonCacheFlutterSecureStorage implements JsonCache {
 
   @override
   Future<bool> contains(String key) async {
-    return _storage.containsKey(key: key);
+    return await _storage.containsKey(key: key);
+  }
+
+  @override
+  Future<UnmodifiableListView<String>> keys() async {
+    return UnmodifiableListView((await _storage.readAll()).keys);
   }
 }
diff --git a/lib/src/json_cache_hive.dart b/lib/src/json_cache_hive.dart
@@ -1,3 +1,4 @@
+import 'dart:collection';
 import 'dart:convert';
 
 import 'package:hive/hive.dart';
@@ -37,4 +38,9 @@ class JsonCacheHive implements JsonCache {
   Future<bool> contains(String key) async {
     return _box.containsKey(key);
   }
+
+  @override
+  Future<UnmodifiableListView<String>> keys() async {
+    return UnmodifiableListView(_box.keys.map((k) => k as String));
+  }
 }
diff --git a/lib/src/json_cache_hollow.dart b/lib/src/json_cache_hollow.dart
@@ -1,3 +1,5 @@
+import 'dart:collection';
+
 import 'package:json_cache/json_cache.dart';
 
 /// Hollow (empty) [JsonCache] — It is intended to serve as a placeholder for
@@ -38,4 +40,9 @@ class JsonCacheHollow implements JsonCache {
   /// Always returns `false`.
   @override
   Future<bool> contains(String key) async => false;
+
+  /// An empty list of keys.
+  @override
+  Future<UnmodifiableListView<String>> keys() async =>
+      UnmodifiableListView(const []);
 }
diff --git a/lib/src/json_cache_local_storage.dart b/lib/src/json_cache_local_storage.dart
@@ -1,3 +1,4 @@
+import 'dart:collection';
 import 'dart:convert';
 
 import 'package:json_cache/json_cache.dart';
@@ -44,4 +45,15 @@ final class JsonCacheLocalStorage implements JsonCache {
 
   @override
   Future<bool> contains(String key) async => _storage.getItem(key) != null;
+
+  @override
+  Future<UnmodifiableListView<String>> keys() async {
+    return UnmodifiableListView(
+      List.generate(
+        _storage.length,
+        (int i) => _storage.key(i)!,
+        growable: false,
+      ),
+    );
+  }
 }
diff --git a/lib/src/json_cache_mem.dart b/lib/src/json_cache_mem.dart
@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:collection';
 
 import 'package:json_cache/json_cache.dart';
 import 'package:mutex/mutex.dart';
@@ -93,8 +94,6 @@ class JsonCacheMem implements JsonCache {
   static final _shrMutex = ReadWriteMutex();
 
   /// Frees up storage space in both the level2 cache and in-memory cache.
-  ///
-  /// Throws [JsonCacheException] to indicate operation failure.
   @override
   Future<void> clear() async {
     await _mutex.protectWrite(() async {
@@ -105,8 +104,6 @@ class JsonCacheMem implements JsonCache {
 
   /// Updates the data located at [key] in both the _level 2_ cache and
   /// in-memory cache.
-  ///
-  /// Throws [JsonCacheException] to indicate operation failure.
   @override
   Future<void> refresh(String key, Map<String, dynamic> data) async {
     // ATTENTION: It is safer to copy the content of [data] before calling an
@@ -160,4 +157,11 @@ class JsonCacheMem implements JsonCache {
       return foundInMemory ? foundInMemory : await _level2.contains(key);
     });
   }
+
+  @override
+  Future<UnmodifiableListView<String>> keys() {
+    return _mutex.protectRead(() async {
+      return UnmodifiableListView(_memory.keys);
+    });
+  }
 }
diff --git a/lib/src/json_cache_safe_local_storage.dart b/lib/src/json_cache_safe_local_storage.dart
@@ -1,5 +1,7 @@
 // ignore_for_file: avoid_dynamic_calls
 
+import 'dart:collection';
+
 import 'package:json_cache/json_cache.dart';
 import 'package:safe_local_storage/safe_local_storage.dart';
 
@@ -43,6 +45,14 @@ class JsonCacheSafeLocalStorage implements JsonCache {
     return (await _cachedData)[key] as Map<String, dynamic>?;
   }
 
+  @override
+  Future<UnmodifiableListView<String>> keys() async {
+    final data = await _cachedData;
+    return UnmodifiableListView(
+      data.keys.map((k) => k as String),
+    );
+  }
+
   /// Gets the cached data stored in the local storage file.
   Future<Map<dynamic, dynamic>> get _cachedData async {
     return await _localStorage.read() as Map<dynamic, dynamic>;
diff --git a/lib/src/json_cache_shared_preferences.dart b/lib/src/json_cache_shared_preferences.dart
@@ -1,3 +1,4 @@
+import 'dart:collection';
 import 'dart:convert';
 
 import 'package:json_cache/json_cache.dart';
@@ -47,4 +48,9 @@ class JsonCacheSharedPreferences implements JsonCache {
   Future<bool> contains(String key) async {
     return _sharedPreferences.containsKey(key);
   }
+
+  @override
+  Future<UnmodifiableListView<String>> keys() async {
+    return UnmodifiableListView(_sharedPreferences.getKeys());
+  }
 }
diff --git a/lib/src/json_cache_try.dart b/lib/src/json_cache_try.dart
@@ -1,3 +1,5 @@
+import 'dart:collection';
+
 import 'package:json_cache/json_cache.dart';
 
 /// A [JsonCache] decorator that provides improved information about
@@ -103,4 +105,19 @@ class JsonCacheTry implements JsonCache {
       );
     }
   }
+
+  @override
+  Future<UnmodifiableListView<String>> keys() async {
+    try {
+      return await _wrapped.keys();
+    } on Exception catch (ex, st) {
+      Error.throwWithStackTrace(
+        JsonCacheException(
+          extra: "Error retreiving the cache keys.",
+          exception: ex,
+        ),
+        st,
+      );
+    }
+  }
 }
diff --git a/lib/src/json_cache_wrap.dart b/lib/src/json_cache_wrap.dart
@@ -1,3 +1,5 @@
+import 'dart:collection';
+
 import 'package:json_cache/json_cache.dart';
 
 /// Decorator Envelope of [JsonCache].
@@ -30,4 +32,8 @@ abstract class JsonCacheWrap implements JsonCache {
   /// Forwards to the [JsonCache.contains] of its wrapped instance.
   @override
   Future<bool> contains(String key) => _wrapped.contains(key);
+
+  /// Forwards to the [JsonCache.keys] of its wrapped instance.
+  @override
+  Future<UnmodifiableListView<String>> keys() => _wrapped.keys();
 }
diff --git a/test/json_cache_fake_test.dart b/test/json_cache_fake_test.dart
@@ -70,6 +70,19 @@ void main() {
       expect(await fake.contains(prefKey), false);
       expect(await fake.contains('a key'), false);
     });
+    test('keys', () async {
+      final profData = <String, dynamic>{'id': 1, 'name': 'John Due'};
+      final prefData = <String, dynamic>{
+        'theme': 'dark',
+        'notifications': {'enabled': true},
+      };
+      final fake = JsonCacheFake();
+      // update data
+      await fake.refresh(profKey, profData);
+      await fake.refresh(prefKey, prefData);
+
+      expect(await fake.keys(), [profKey, prefKey]);
+    });
     group('remove', () {
       test('default ctor', () async {
         final JsonCacheFake fakeCache = JsonCacheFake();
diff --git a/test/json_cache_mem_test.dart b/test/json_cache_mem_test.dart
@@ -130,6 +130,19 @@ void main() {
       expect(await memCache.contains(prefKey), false);
       expect(await memCache.contains('a key'), false);
     });
+    test('keys', () async {
+      final profData = <String, dynamic>{'id': 1, 'name': 'John Due'};
+      final prefData = <String, dynamic>{
+        'theme': 'dark',
+        'notifications': {'enabled': true},
+      };
+      final memCache = JsonCacheMem();
+      // update data
+      await memCache.refresh(profKey, profData);
+      await memCache.refresh(prefKey, prefData);
+
+      expect(await memCache.keys(), [profKey, prefKey]);
+    });
     group('remove', () {
       test('default ctor', () async {
         final JsonCacheMem memCache = JsonCacheMem();
diff --git a/test/json_cache_shared_preferences_test.dart b/test/json_cache_shared_preferences_test.dart
@@ -5,9 +5,14 @@ import 'package:shared_preferences/shared_preferences.dart';
 void main() {
   SharedPreferences.setMockInitialValues({});
   group('JsonCacheSharedPreferences', () {
+    const profKey = 'profile';
+    const prefKey = 'preferences';
+    final profData = <String, dynamic>{'id': 1, 'name': 'John Due'};
+    final prefData = <String, dynamic>{
+      'theme': 'dark',
+      'notifications': {'enabled': true},
+    };
     test('clear, value, refresh', () async {
-      const profKey = 'profile';
-      const profData = <String, Object>{'id': 1, 'name': 'John Due'};
       final JsonCacheSharedPreferences prefsCache =
           JsonCacheSharedPreferences(await SharedPreferences.getInstance());
       await prefsCache.refresh(profKey, profData);
@@ -19,13 +24,6 @@ void main() {
     });
 
     test('contains', () async {
-      const profKey = 'profile';
-      const prefKey = 'preferences';
-      final profData = <String, dynamic>{'id': 1, 'name': 'John Due'};
-      final prefData = <String, dynamic>{
-        'theme': 'dark',
-        'notifications': {'enabled': true},
-      };
       final JsonCacheSharedPreferences prefs =
           JsonCacheSharedPreferences(await SharedPreferences.getInstance());
       // update data
@@ -43,14 +41,17 @@ void main() {
       await prefs.remove(prefKey);
       expect(await prefs.contains(prefKey), false);
     });
+
+    test('keys', () async {
+      final JsonCacheSharedPreferences prefs =
+          JsonCacheSharedPreferences(await SharedPreferences.getInstance());
+      // update data
+      await prefs.refresh(profKey, profData);
+      await prefs.refresh(prefKey, prefData);
+
+      expect(await prefs.keys(), [profKey, prefKey]);
+    });
     test('remove', () async {
-      const profKey = 'profile';
-      const prefKey = 'preferences';
-      final profData = <String, Object>{'id': 1, 'name': 'John Due'};
-      final prefData = <String, Object>{
-        'theme': 'dark',
-        'notifications': {'enabled': true},
-      };
       final JsonCacheSharedPreferences prefsCache =
           JsonCacheSharedPreferences(await SharedPreferences.getInstance());
       await prefsCache.refresh(profKey, profData);

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,5 @@`
	`1`	`+import 'dart:collection';`
	`2`	`+`
`1`	`3`	`import 'package:json_cache/json_cache.dart';`
`2`	`4`
`3`	`5`	`/// In-memory cache without synchronization.`
`@@ -50,4 +52,9 @@ class JsonCacheFake implements JsonCache {`
`50`	`52`	`Future<bool> contains(String key) async {`
`51`	`53`	`return _memory.containsKey(key);`
`52`	`54`	`}`
	`55`	`+`
	`56`	`+ @override`
	`57`	`+ Future<UnmodifiableListView<String>> keys() async {`
	`58`	`+ return UnmodifiableListView(_memory.keys);`
	`59`	`+ }`
`53`	`60`	`}`
Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,4 @@`
	`1`	`+import 'dart:collection';`
`1`	`2`	`import 'dart:convert';`
`2`	`3`
`3`	`4`	`import 'package:hive/hive.dart';`
`@@ -37,4 +38,9 @@ class JsonCacheHive implements JsonCache {`
`37`	`38`	`Future<bool> contains(String key) async {`
`38`	`39`	`return _box.containsKey(key);`
`39`	`40`	`}`
	`41`	`+`
	`42`	`+ @override`
	`43`	`+ Future<UnmodifiableListView<String>> keys() async {`
	`44`	`+ return UnmodifiableListView(_box.keys.map((k) => k as String));`
	`45`	`+ }`
`40`	`46`	`}`