local_first_icloud_backup 0.1.0

iCloud backup provider for local_first: backup and restore app data using iCloud Documents on iOS/macOS.

local_first_icloud_backup

An iCloud backup provider for the LocalFirst framework. Backup and restore your local-first data using iCloud Documents — the same approach used by WhatsApp on iOS.

Note: This is a companion package to local_first. You need to install the core package first.

Why local_first_icloud_backup?

• WhatsApp-style backups: Uses iCloud Documents, the native iOS/macOS backup mechanism
• AES-256 encryption: Backups are encrypted with a user-provided password before upload
• Zero authentication: Automatically uses the device's Apple ID — no sign-in flow needed
• Native integration: Uses Apple's iCloud APIs for reliable cloud storage
• Simple API: Upload, download, list, and delete backups with a single method call
• Incremental restore: Restores merge with existing data instead of overwriting

Features

• ✅ iCloud Documents Storage: Native Apple cloud storage integration
• ✅ Automatic Authentication: Uses the device's Apple ID — no sign-in required
• ✅ Upload/Download Backups: Full backup lifecycle management
• ✅ List Available Backups: Browse and select backups to restore
• ✅ Delete Old Backups: Clean up iCloud storage when no longer needed
• ✅ Configurable Subfolder: Organize backups in custom subdirectories
• ✅ Full Test Coverage: Comprehensive unit tests with mocked iCloud APIs

Platform Support

Platform	Supported
iOS	✅
macOS	✅
Android	❌
Windows	❌
Linux	❌
Web	❌

Throws UnsupportedError on non-Apple platforms.

Installation

Add the dependencies to your pubspec.yaml:

dependencies:
  local_first: ^0.7.0
  local_first_icloud_backup: ^0.1.0
  # Choose your storage adapter
  local_first_hive_storage: ^0.2.0  # or
  local_first_sqlite_storage: ^0.3.0

Then install:

flutter pub get

Setup

Xcode Configuration

1. Open your project in Xcode
2. Select your target → Signing & Capabilities
3. Click + Capability → add iCloud
4. Enable iCloud Documents
5. Add your container identifier (e.g., iCloud.com.example.myapp)

Info.plist (iOS)

Ensure iCloud entitlements are properly configured. Xcode usually handles this automatically when you add the capability.

Entitlements (macOS)

For macOS, also add the following to your .entitlements file:

<key>com.apple.developer.icloud-container-identifiers</key>
<array>
    <string>iCloud.com.example.myapp</string>
</array>
<key>com.apple.developer.ubiquity-container-identifiers</key>
<array>
    <string>iCloud.com.example.myapp</string>
</array>

Quick Start

import 'package:local_first/local_first.dart';
import 'package:local_first_icloud_backup/local_first_icloud_backup.dart';

// 1) Create the provider (no sign-in needed!)
final icloudProvider = ICloudBackupProvider(
  containerId: 'iCloud.com.example.myapp',
  subfolder: 'my_app_backups', // optional, defaults to 'local_first_backups'
);

// 2) Create the backup service
final backupService = BackupService(client: myLocalFirstClient);

// 3) Create a backup
final metadata = await backupService.createBackup(
  provider: icloudProvider,
  password: 'user-chosen-password',
);
print('Backup created: ${metadata.fileName} (${metadata.sizeInBytes} bytes)');

// 4) List available backups
final backups = await backupService.listBackups(icloudProvider);
for (final backup in backups) {
  print('${backup.fileName} - ${backup.createdAt}');
}

// 5) Restore from a backup
await backupService.restoreBackup(
  provider: icloudProvider,
  metadata: backups.first,
  password: 'user-chosen-password',
);

// 6) Delete a backup
await backupService.deleteBackup(
  provider: icloudProvider,
  metadata: backups.last,
);

How It Works

Backup Flow

┌──────────────────┐     ┌──────────────────┐     ┌──────────────────┐
│  LocalFirstClient│────▶│  BackupService    │────▶│  ICloudBackup    │
│                  │     │                   │     │  Provider        │
│  - repositories  │     │  1. Collect data  │     │                  │
│  - events        │     │  2. JSON encode   │     │  Write temp file │
│  - config        │     │  3. Gzip compress  │     │  Upload to iCloud│
│                  │     │  4. AES-256 encrypt│     │  Clean up temp   │
└──────────────────┘     └──────────────────┘     └──────────────────┘

Restore Flow

┌──────────────────┐     ┌──────────────────┐     ┌──────────────────┐
│  ICloudBackup    │────▶│  BackupService    │────▶│  LocalFirstClient│
│  Provider        │     │                   │     │                  │
│                  │     │  1. AES-256 decrypt│     │  Incremental     │
│  Download from   │     │  2. Gunzip         │     │  merge via       │
│  iCloud Documents│     │  3. JSON decode    │     │  pullChanges()   │
│  Clean up temp   │     │  4. Restore config │     │                  │
└──────────────────┘     └──────────────────┘     └──────────────────┘

Architecture

iCloud Documents

iCloud Documents provides native Apple cloud storage:

• Automatic sync — Apple handles upload/download synchronization
• Offline support — files are cached locally and synced when online
• Apple ID auth — no separate sign-in needed, uses the device's Apple ID
• Cross-device — backups are accessible on any device with the same Apple ID

Storage Structure

iCloud Container (iCloud.com.example.myapp)/
└── local_first_backups/           ← configurable via subfolder
    ├── backup_2026-03-01T12:00:00Z.lfbk
    ├── backup_2026-03-05T08:30:00Z.lfbk
    └── backup_2026-03-09T15:45:00Z.lfbk

Configuration

Container ID

The container ID must match your Xcode iCloud entitlement:

final provider = ICloudBackupProvider(
  containerId: 'iCloud.com.example.myapp', // must match Xcode config
);

Custom Subfolder

Organize backups in a custom subdirectory:

final provider = ICloudBackupProvider(
  containerId: 'iCloud.com.example.myapp',
  subfolder: 'production_backups',
);

Comparison with Other Providers

Feature	iCloud	GDrive	Firebase Storage
Platform	iOS, macOS only	Android, iOS, Web	All platforms
Auth	Automatic (Apple ID)	Google Sign-In	Firebase Auth
Storage Location	iCloud Documents	App Data folder	Firebase Storage
User Visibility	Visible in iCloud	Hidden	Hidden
Quota Impact	Yes (iCloud quota)	No	Yes (Firebase quota)
Best For	Apple-only apps	Android-first apps	Cross-platform apps

Best Practices

1. Match container IDs: Ensure containerId matches your Xcode iCloud entitlement exactly
2. Check platform: The provider throws UnsupportedError on non-Apple platforms — guard with Platform.isIOS || Platform.isMacOS
3. Limit backup count: Delete old backups to avoid excessive iCloud storage usage
4. Use strong passwords: The encryption is only as strong as the user's password
5. Test on real devices: iCloud functionality requires a real Apple ID and device

Troubleshooting

UnsupportedError on Construction

• This provider only works on iOS and macOS
• Use GDriveBackupProvider or FirebaseBackupProvider for other platforms

Upload Fails

• Verify the container ID matches your Xcode iCloud entitlement
• Check that iCloud is enabled on the device (Settings → Apple ID → iCloud)
• Ensure the device has sufficient iCloud storage

Backups Not Appearing

• iCloud sync may take a few seconds — wait and retry
• Verify you're using the same subfolder for upload and list operations
• Check that the Apple ID is the same on all devices

Entitlement Errors

• Re-add the iCloud capability in Xcode
• Clean and rebuild the project
• Verify your provisioning profile includes iCloud entitlements

Testing

import 'package:flutter_test/flutter_test.dart';
import 'package:local_first_icloud_backup/local_first_icloud_backup.dart';
import 'package:mocktail/mocktail.dart';

class MockDelegate extends Mock implements ICloudStorageDelegate {}

void main() {
  test('uploads backup to iCloud', () async {
    final mockDelegate = MockDelegate();
    final provider = ICloudBackupProvider(
      containerId: 'iCloud.com.test',
      delegate: mockDelegate,
    );

    // ... set up mocks and test
  });
}

Contributing

Contributions are welcome. See CONTRIBUTING.md for guidelines.

Support the Project 💰

Your contributions help us enhance and maintain our plugins. Donations are used to procure devices and equipment for testing compatibility across platforms and versions.

License

This project is available under the MIT License. See LICENSE for details.