📶 Dio Offline Queue

A robust, 100% customizable, and production-ready Dio interceptor that automatically catches failed network requests (POST, PUT, DELETE, PATCH) when the device is offline, saves them, and replays them in FIFO order once connectivity is restored.

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🚀 Features

• Automatic Queuing: Catches DioException related to connectivity and saves requests.
• FIFO Replay: Ensures data consistency by replaying requests in the order they were made.
• Fully Abstracted: Swap out storage, network observation, or retry logic with your own implementations.
• Sensible Defaults: Comes with InMemoryQueueStorage and ConnectivityPlusObserver out-of-the-box.
• Safe by Default: Only queues non-GET requests by default to prevent side-effect issues.

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📦 Installation

Add the following to your pubspec.yaml:

dependencies:
  dio_offline_queue: ^1.0.0

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🛠️ Quick Start

import 'package:dio/dio.dart';
import 'package:dio_offline_queue/dio_offline_queue.dart';

void main() {
  final dio = Dio();

  // 1. Setup the manager with default implementations
  final manager = OfflineQueueManager(
    dio: dio,
    storage: InMemoryQueueStorage(),
    networkObserver: ConnectivityPlusObserver(),
    retryPolicy: DefaultRetryPolicy(),
  );

  // 2. Add the interceptor to your Dio instance
  dio.interceptors.add(OfflineQueueInterceptor(manager: manager));

  // 3. That's it! Requests made while offline will now be queued and replayed.
}

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⚙️ Advanced Customization

💾 Persistent Storage (Hive/SQLite)

The default InMemoryQueueStorage will lose data if the app is closed. For production, implement the QueueStorage interface using your preferred database:

class MyHiveStorage implements QueueStorage {
  @override
  Future<void> add(QueuedRequest request) async {
    final box = await Hive.openBox('queue');
    await box.put(request.id, request.toJson());
  }
  // Implement other methods...
}

🔄 Custom Retry Policy

Control exactly when and how requests should be retried:

final retryPolicy = DefaultRetryPolicy(
  maxAttempts: 10,
  retryDelay: Duration(seconds: 10),
);

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🤝 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.