offline_sync_core 0.1.6 
offline_sync_core: ^0.1.6 copied to clipboard
A robust, production-ready Flutter package for offline-first caching and synchronization. Features smart TTL cache, offline sync queue with auto-retry, optimistic UI updates, periodic background sync, [...]
import 'package:flutter/material.dart';
import 'package:offline_sync_core/offline_sync_core.dart';
void main() async {
WidgetsFlutterBinding.ensureInitialized();
// Initialize offline_sync_core with Hive and logging enabled
await OfflineSyncCore.initialize(
storage: HiveStorage(),
config: const OfflineSyncConfig(
enableLogging: true,
maxRetries: 3,
),
);
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
@override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'offline_sync_core',
theme: ThemeData.dark().copyWith(
scaffoldBackgroundColor: const Color(0xFF0F0F1A),
colorScheme: const ColorScheme.dark().copyWith(
primary: const Color(0xFF7C3AED),
secondary: const Color(0xFF10B981),
surface: const Color(0xFF1A1A2E),
),
),
home: const HomePage(),
);
}
}
class HomePage extends StatefulWidget {
const HomePage({super.key});
@override
State<HomePage> createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
final TextEditingController _nameController = TextEditingController();
String _cacheStatus = 'No data loaded';
bool _isLoading = false;
bool _fromCache = false;
@override
void initState() {
super.initState();
_loadUser();
}
@override
void dispose() {
_nameController.dispose();
super.dispose();
}
// Showcase Smart Caching & TTL
Future<void> _loadUser() async {
setState(() => _isLoading = true);
try {
final start = DateTime.now();
final user = await OfflineSyncCore.get<Map>(
key: 'user_profile',
ttl: const Duration(seconds: 15),
fetch: () async {
await Future.delayed(const Duration(seconds: 2));
return {
'name': 'Pawan Kushwaha',
'email': 'pawan@example.com',
'role': 'Flutter Developer',
'fetchedAt': DateTime.now().toIso8601String(),
};
},
);
final elapsed = DateTime.now().difference(start).inMilliseconds;
setState(() {
_fromCache = elapsed < 500;
if (user != null) {
_cacheStatus = '👤 Name: ${user['name']}\n'
'📧 Email: ${user['email']}\n'
'💼 Role: ${user['role']}\n'
'🕒 Loaded At: ${user['fetchedAt'].toString().substring(11, 19)}';
} else {
_cacheStatus = 'No profile data found';
}
_isLoading = false;
});
} catch (e) {
setState(() {
_cacheStatus = 'Error loading data: $e';
_isLoading = false;
});
}
}
// Showcase Offline Sync & Immediate Local Cache Update
Future<void> _updateProfileOffline() async {
final newName = _nameController.text.trim();
if (newName.isEmpty) {
ScaffoldMessenger.of(context).showSnackBar(
const SnackBar(
content: Text('⚠️ Please enter a new profile name!'),
backgroundColor: Colors.orange,
),
);
return;
}
setState(() => _isLoading = true);
// 1. Manually update the local cache immediately (Optimistic Cache Update)
final updatedProfile = {
'name': newName,
'email': '${newName.toLowerCase().replaceAll(' ', '')}@example.com',
'role': 'Flutter Developer (Updated)',
'fetchedAt': DateTime.now().toIso8601String(),
};
await OfflineSyncCore.put(
key: 'user_profile',
data: updatedProfile,
ttl: const Duration(seconds: 15),
);
// 2. Queue the mutation task to sync with server in background
final task = SyncTask(
url: 'https://jsonplaceholder.typicode.com/users/1',
method: 'PUT',
body: updatedProfile,
);
await OfflineSyncCore.enqueue(task);
// 3. Immediately refresh UI with new local cache (instant update, no 2s delay)
await _loadUser();
if (mounted) {
ScaffoldMessenger.of(context).showSnackBar(
SnackBar(
content: Text('📝 Local cache updated to "$newName" & Sync Task queued!'),
backgroundColor: const Color(0xFF10B981),
duration: const Duration(seconds: 2),
),
);
}
_nameController.clear();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
backgroundColor: const Color(0xFF1A1A2E),
title: const Text(
'⚡ Offline Sync Core',
style: TextStyle(fontWeight: FontWeight.bold),
),
actions: [
IconButton(
icon: const Icon(Icons.bug_report, color: Color(0xFF7C3AED)),
onPressed: () {
// Open Visual Inspector Screen
Navigator.push(
context,
MaterialPageRoute(
builder: (_) => InspectorScreen(
controller: InspectorController(
storage: HiveStorage(),
syncManager: OfflineSyncCore.syncManager,
),
),
),
);
},
tooltip: 'Open Inspector',
),
],
),
body: SingleChildScrollView(
padding: const EdgeInsets.all(20),
child: Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: [
// Smart Cache Card
Card(
color: const Color(0xFF1A1A2E),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(15),
side: const BorderSide(color: Colors.white10),
),
child: Padding(
padding: const EdgeInsets.all(20),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
crossAxisAlignment: CrossAxisAlignment.start,
children: [
const Expanded(
child: Text(
'🗄️ Smart Cache (TTL: 15s)',
style: TextStyle(
fontSize: 16,
fontWeight: FontWeight.bold,
color: Color(0xFF7C3AED),
),
),
),
const SizedBox(width: 8),
if (_isLoading)
const SizedBox(
width: 16,
height: 16,
child: CircularProgressIndicator(
strokeWidth: 2,
color: Color(0xFF7C3AED),
),
)
else if (_cacheStatus != 'No data loaded')
AnimatedSwitcher(
duration: const Duration(milliseconds: 400),
child: Chip(
key: ValueKey(_fromCache),
avatar: Icon(
_fromCache
? Icons.flash_on
: Icons.cloud_download,
size: 14,
color: _fromCache
? Colors.amber
: Colors.blueAccent,
),
label: Text(
_fromCache ? '⚡ CACHE' : '🌐 NETWORK',
style: TextStyle(
fontSize: 10,
fontWeight: FontWeight.bold,
color: _fromCache
? Colors.amber
: Colors.blueAccent,
),
),
backgroundColor: _fromCache
? Colors.amber.withValues(alpha: 0.12)
: Colors.blueAccent.withValues(alpha: 0.12),
side: BorderSide(
color: _fromCache
? Colors.amber
: Colors.blueAccent,
),
padding: EdgeInsets.zero,
visualDensity: VisualDensity.compact,
),
),
],
),
const SizedBox(height: 15),
Text(
_cacheStatus,
style: const TextStyle(
fontSize: 14,
height: 1.6,
color: Colors.white70,
),
),
const SizedBox(height: 15),
ElevatedButton.icon(
onPressed: _isLoading ? null : _loadUser,
icon: const Icon(Icons.refresh),
label: const Text('Fetch / Refresh Cache'),
style: ElevatedButton.styleFrom(
backgroundColor: const Color(0xFF7C3AED),
foregroundColor: Colors.white,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10),
),
),
),
],
),
),
),
const SizedBox(height: 20),
// Queue Operations Card
Card(
color: const Color(0xFF1A1A2E),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(15),
side: const BorderSide(color: Colors.white10),
),
child: Padding(
padding: const EdgeInsets.all(20),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
const Text(
'📤 Update Profile Offline & Sync',
style: TextStyle(
fontSize: 18,
fontWeight: FontWeight.bold,
color: Color(0xFF10B981),
),
),
const SizedBox(height: 10),
const Text(
'Type a name, turn off the internet, and save. The local UI updates instantly while the sync is queued.',
style: TextStyle(color: Colors.white54, fontSize: 14),
),
const SizedBox(height: 15),
TextField(
controller: _nameController,
decoration: const InputDecoration(
labelText: 'Enter New Profile Name (e.g. Shivam)',
border: OutlineInputBorder(),
focusedBorder: OutlineInputBorder(
borderSide: BorderSide(color: Color(0xFF10B981)),
),
labelStyle: TextStyle(color: Colors.white54),
),
style: const TextStyle(color: Colors.white),
),
const SizedBox(height: 15),
ElevatedButton.icon(
onPressed: _updateProfileOffline,
icon: const Icon(Icons.sync_alt),
label: const Text('Update Profile & Queue Sync'),
style: ElevatedButton.styleFrom(
backgroundColor: const Color(0xFF10B981),
foregroundColor: Colors.white,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10),
),
),
),
],
),
),
),
const SizedBox(height: 20),
// Visual Debugger Button
ElevatedButton.icon(
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (_) => InspectorScreen(
controller: InspectorController(
storage: HiveStorage(),
syncManager: OfflineSyncCore.syncManager,
),
),
),
);
},
icon: const Icon(Icons.troubleshoot),
label: const Text('Open Visual Sync Inspector'),
style: ElevatedButton.styleFrom(
backgroundColor: const Color(0xFF1E1B4B),
foregroundColor: const Color(0xFFC084FC),
side: const BorderSide(color: Color(0xFF6B21A8)),
padding: const EdgeInsets.symmetric(vertical: 15),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(12),
),
),
),
],
),
),
);
}
}Metadata
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unverified uploader
Weekly Downloads
Metadata
A robust, production-ready Flutter package for offline-first caching and synchronization. Features smart TTL cache, offline sync queue with auto-retry, optimistic UI updates, periodic background sync, SQLite & Hive adapters, and a built-in visual debug inspector.
Homepage
Repository (GitHub)
View/report issues
Topics
#offline #cache #sync #hive #networking
License
MIT (license)
Dependencies
connectivity_plus, crypto, flutter, hive, hive_flutter, http, json_annotation, logger, path, path_provider, rxdart, sqflite, synchronized, uuid, workmanager