Storage

Introduction

Nylo Website v7 provides a powerful storage system through the NyStorage class. It uses flutter_secure_storage under the hood to store data securely on the user's device.

import 'package:nylo_framework/nylo_framework.dart';

// Save a value
await NyStorage.save("coins", 100);

// Read a value
int? coins = await NyStorage.read<int>('coins'); // 100

// Delete a value
await NyStorage.delete('coins');

Save Values

Save values using NyStorage.save() or the storageSave() helper:

// Using NyStorage class
await NyStorage.save("username", "Anthony");
await NyStorage.save("score", 1500);
await NyStorage.save("isPremium", true);

// Using helper function
await storageSave("username", "Anthony");

Save to Backpack Simultaneously

Store in both persistent storage and in-memory Backpack:

await NyStorage.save('auth_token', 'abc123', inBackpack: true);

// Now accessible synchronously via Backpack
String? token = Backpack.instance.read('auth_token');

Read Values

Read values with automatic type casting:

// Read as String (default)
String? username = await NyStorage.read('username');

// Read with type casting
int? score = await NyStorage.read<int>('score');
double? rating = await NyStorage.read<double>('rating');
bool? isPremium = await NyStorage.read<bool>('isPremium');

// With default value
String name = await NyStorage.read('name', defaultValue: 'Guest') ?? 'Guest';

// Using helper function
String? username = await storageRead('username');
int? score = await storageRead<int>('score');

Delete Values

// Delete a single key
await NyStorage.delete('username');

// Delete and remove from Backpack too
await NyStorage.delete('auth_token', andFromBackpack: true);

// Delete multiple keys
await NyStorage.deleteMultiple(['key1', 'key2', 'key3']);

// Delete all (with optional exclusions)
await NyStorage.deleteAll();
await NyStorage.deleteAll(excludeKeys: ['auth_token']);

Storage Keys

Organize your storage keys in lib/config/storage_keys.dart:

final class StorageKeysConfig {
  // Auth key for user authentication
  static StorageKey auth = 'SK_AUTH';

  // Keys synced on app boot
  static syncedOnBoot() => () async {
    return [
      coins.defaultValue(0),
      themePreference.defaultValue('light'),
    ];
  };

  static StorageKey coins = 'SK_COINS';
  static StorageKey themePreference = 'SK_THEME_PREFERENCE';
  static StorageKey onboardingComplete = 'SK_ONBOARDING_COMPLETE';
}

Using StorageKey Extensions

StorageKey is a typedef for String, and comes with a powerful set of extension methods:

// Save
await StorageKeysConfig.coins.save(100);

// Save with Backpack
await StorageKeysConfig.coins.save(100, inBackpack: true);

// Read
int? coins = await StorageKeysConfig.coins.read<int>();

// Read with default value
int? coins = await StorageKeysConfig.coins.fromStorage<int>(defaultValue: 0);

// Save/Read JSON
await StorageKeysConfig.coins.saveJson({"gold": 50, "silver": 200});
Map? data = await StorageKeysConfig.coins.readJson<Map>();

// Delete
await StorageKeysConfig.coins.deleteFromStorage();

// Delete (alias)
await StorageKeysConfig.coins.flush();

// Read from Backpack (synchronous)
int? coins = StorageKeysConfig.coins.fromBackpack<int>();

// Collection operations
await StorageKeysConfig.coins.addToCollection<int>(100);
List<int> allCoins = await StorageKeysConfig.coins.readCollection<int>();

Save/Read JSON

Store and retrieve JSON data:

// Save JSON
Map<String, dynamic> user = {
  "name": "Anthony",
  "email": "anthony@example.com",
  "preferences": {"theme": "dark"}
};
await NyStorage.saveJson("user_data", user);

// Read JSON
Map<String, dynamic>? userData = await NyStorage.readJson("user_data");
print(userData?['name']); // "Anthony"

TTL (Time-to-Live)

Nylo Website v7 supports storing values with automatic expiration:

// Save with 1 hour expiration
await NyStorage.saveWithExpiry(
  'session_token',
  'abc123',
  ttl: Duration(hours: 1),
);

// Read (returns null if expired)
String? token = await NyStorage.readWithExpiry<String>('session_token');

// Check remaining time
Duration? remaining = await NyStorage.getTimeToLive('session_token');
if (remaining != null) {
  print('Expires in ${remaining.inMinutes} minutes');
}

// Clean up all expired keys
int removed = await NyStorage.removeExpired();
print('Removed $removed expired keys');

Batch Operations

Efficiently handle multiple storage operations:

// Save multiple values
await NyStorage.saveAll({
  'username': 'Anthony',
  'score': 1500,
  'level': 10,
});

// Read multiple values
Map<String, dynamic?> values = await NyStorage.readMultiple<dynamic>([
  'username',
  'score',
  'level',
]);

// Delete multiple keys
await NyStorage.deleteMultiple(['temp_1', 'temp_2', 'temp_3']);

Introduction to Collections

Collections allow you to store lists of items under a single key:

// Add items to a collection
await NyStorage.addToCollection("favorites", item: "Product A");
await NyStorage.addToCollection("favorites", item: "Product B");

// Read the collection
List<String> favorites = await NyStorage.readCollection<String>("favorites");
// ["Product A", "Product B"]

Add to Collection

// Add item (allows duplicates by default)
await NyStorage.addToCollection("cart_ids", item: 123);

// Prevent duplicates
await NyStorage.addToCollection(
  "cart_ids",
  item: 123,
  allowDuplicates: false,
);

// Save entire collection at once
await NyStorage.saveCollection<int>("cart_ids", [1, 2, 3, 4, 5]);

Read Collection

// Read collection with type
List<int> cartIds = await NyStorage.readCollection<int>("cart_ids");

// Check if collection is empty
bool isEmpty = await NyStorage.isCollectionEmpty("cart_ids");

Update Collection

// Update item by index
await NyStorage.updateCollectionByIndex<int>(
  0, // index
  (item) => item + 10, // transform function
  key: "scores",
);

// Update items matching a condition
await NyStorage.updateCollectionWhere<Map<String, dynamic>>(
  (item) => item['id'] == 5, // where condition
  key: "products",
  update: (item) {
    item['quantity'] = item['quantity'] + 1;
    return item;
  },
);

Delete from Collection

// Delete by index
await NyStorage.deleteFromCollection<String>(0, key: "favorites");

// Delete by value
await NyStorage.deleteValueFromCollection<int>(
  "cart_ids",
  value: 123,
);

// Delete items matching a condition
await NyStorage.deleteFromCollectionWhere<Map<String, dynamic>>(
  (item) => item['expired'] == true,
  key: "coupons",
);

// Delete entire collection
await NyStorage.delete("favorites");

Backpack Storage

Backpack is a lightweight in-memory storage class for quick synchronous access during a user's session. Data is not persisted when the app closes.

Save to Backpack

// Using helper
backpackSave('user_token', 'abc123');
backpackSave('user', userObject);

// Using Backpack directly
Backpack.instance.save('settings', {'darkMode': true});

Read from Backpack

// Using helper
String? token = backpackRead('user_token');
User? user = backpackRead<User>('user');

// Using Backpack directly
var settings = Backpack.instance.read('settings');

Delete from Backpack

backpackDelete('user_token');

// Delete all
backpackDeleteAll();

Practical Example

// After login, store token in both persistent and session storage
Future<void> handleLogin(String token) async {
  // Persist for app restarts
  await NyStorage.save('auth_token', token);

  // Also store in Backpack for quick access
  backpackSave('auth_token', token);
}

// In API service, access synchronously
class ApiService extends NyApiService {
  Future<User?> getProfile() async {
    return await network<User>(
      request: (request) => request.get("/profile"),
      bearerToken: backpackRead('auth_token'), // No await needed
    );
  }
}

Persist with Backpack

Store in both persistent storage and Backpack in one call:

// Save to both
await NyStorage.save('user_token', 'abc123', inBackpack: true);

// Now accessible via Backpack (sync) and NyStorage (async)
String? tokenSync = Backpack.instance.read('user_token');
String? tokenAsync = await NyStorage.read('user_token');

Sync Storage to Backpack

Load all persistent storage into Backpack on app boot:

// In your app provider
await NyStorage.syncToBackpack();

// With overwrite option
await NyStorage.syncToBackpack(overwrite: true);

Sessions

Sessions provide named, in-memory storage for grouping related data (not persisted):

// Create/access a session and add data
session('checkout')
    .add('items', ['Product A', 'Product B'])
    .add('total', 99.99)
    .add('coupon', 'SAVE10');

// Or initialize with data
session('checkout', {
  'items': ['Product A', 'Product B'],
  'total': 99.99,
});

// Read session data
List<String>? items = session('checkout').get<List<String>>('items');
double? total = session('checkout').get<double>('total');

// Get all session data
Map<String, dynamic>? checkoutData = session('checkout').data();

// Delete a single value
session('checkout').delete('coupon');

// Clear entire session
session('checkout').clear();
// or
session('checkout').flush();

Persist Sessions

Sessions can be synced to persistent storage:

// Save session to storage
await session('checkout').syncToStorage();

// Restore session from storage
await session('checkout').syncFromStorage();

Session Use Cases

Sessions are ideal for:

• Multi-step forms (onboarding, checkout)
• Temporary user preferences
• Wizard/journey flows
• Shopping cart data

Model Save

The Model base class provides built-in storage methods. When you define a key in the constructor, the model can save itself:

class User extends Model {
  String? name;
  String? email;

  // Define a storage key
  static StorageKey key = 'user';
  User() : super(key: key);

  User.fromJson(dynamic data) : super(key: key) {
    name = data['name'];
    email = data['email'];
  }

  @override
  Map<String, dynamic> toJson() => {
    "name": name,
    "email": email,
  };
}

Saving a Model

User user = User();
user.name = "Anthony";
user.email = "anthony@example.com";

// Save to persistent storage
await user.save();

// Save to both storage and Backpack
await user.save(inBackpack: true);

Reading a Model Back

User? user = await NyStorage.read<User>(User.key);

Syncing to Backpack

Load a model from storage into Backpack for synchronous access:

bool found = await User().syncToBackpack();
if (found) {
  User? user = Backpack.instance.read<User>(User.key);
}

Model Collections

Save models to a collection:

User userAnthony = User();
userAnthony.name = 'Anthony';
await userAnthony.saveToCollection();

User userKyle = User();
userKyle.name = 'Kyle';
await userKyle.saveToCollection();

// Read back
List<User> users = await NyStorage.readCollection<User>(User.key);

StorageKey Extension Reference

StorageKey is a typedef for String. The NyStorageKeyExt extension provides these methods:

Storage Exceptions

Nylo Website v7 provides typed storage exceptions:

try {
  await NyStorage.read<User>('user');
} on StorageDeserializationException catch (e) {
  print('Failed to load user: ${e.message}');
  print('Expected type: ${e.expectedType}');
}

Legacy Migration

Nylo Website v7 uses a new envelope storage format. If you're upgrading from v6, you can migrate old data:

// Call during app initialization
int migrated = await NyStorage.migrateToEnvelopeFormat();
print('Migrated $migrated keys to new format');

This converts legacy format (separate _runtime_type keys) to the new envelope format. The migration is safe to run multiple times - already-migrated keys are skipped.