offline_sync 0.0.1

A package designed to manage and synchronize data offline-first, ensuring seamless functionality independent of internet connectivity, with automatic syncing upon restoration of connection.

OfflineSync

OfflineSync is a Flutter package that provides offline-first data management and synchronization. It ensures smooth functionality even without an internet connection and syncs data once connectivity is restored.

Features

• Local data storage and retrieval
• Automatic synchronization with server when online
• Conflict resolution
• Encryption of sensitive data
• Batch syncing for improved performance
• Error handling and retry mechanisms

Installation

Add this to your package's pubspec.yaml file:

dependencies:
  offline_sync: ^0.0.1

Usage

Initialization

First, initialize the OfflineSync instance in your app:

import 'package:offline_sync/offline_sync.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  final offlineSync = OfflineSync();
  await offlineSync.initialize();
  runApp(MyApp());
}

Setting Custom API Endpoint

Set a custom endpoint for your specific server:

final offlineSync = OfflineSync();
offlineSync.setApiEndpoint('https://your-custom-api.com');

Saving Data

To save data locally and queue it for syncing:

final offlineSync = OfflineSync();
await offlineSync.saveLocalData('user_1', {
  'name': 'John Doe',
  'email': '[e-mail]',
  'age': 30,
});

Reading Data

To read locally stored data:

final userData = await offlineSync.readLocalData('user_1');
if (userData != null) {
  print('User name: ${userData['name']}');
} else {
  print('User not found');
}

Syncing with Server

The package automatically syncs data when an internet connection is available. However, you can manually trigger a sync:

try {
  await offlineSync.updateFromServer();
  print('Data updated from server successfully');
} catch (e) {
  print('Failed to update from server: $e');
}

Handling Authentication

Set the authentication token for API requests:

await offlineSync.setAuthToken('your_auth_token_here');

Advanced Usage:

Conflict Resolution

The package includes basic conflict resolution. You can customize this by extending the OfflineSync class:

class CustomOfflineSync extends OfflineSync {
  @override
  Future<Map<String, dynamic>> resolveConflict(
    String id, 
    Map<String, dynamic> localData, 
    Map<String, dynamic> serverData
  ) async {
    // Implement your custom conflict resolution strategy here
    // This example prefers local changes
    final resolvedData = Map<String, dynamic>.from(serverData);
    localData.forEach((key, value) {
      if (value != serverData[key]) {
        resolvedData[key] = value;
      }
    });
    return resolvedData;
  }
}

Batch Processing

The package processes sync queue in batches. You can adjust the batch size:

class CustomOfflineSync extends OfflineSync {
  @override
  int get batchSize => 100; // Default is 50
}

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.