storage/storage library

Zenify Storage Adapters

Zenify ships zero third-party dependencies. The ZenStorage interface is intentionally minimal so you can plug in any persistence backend.

Important: the wire format is Map<String, dynamic>, not a JSON string

ZenStorage.write() and read() pass a plain Dart map. There is no jsonEncode/jsonDecode anywhere in the ZenQuery cache layer itself. This means ZenQueryConfig.toJson/fromJson are actually Map<String, dynamic> converters — Drift's toMap()/fromMap() plug in directly without any extra encoding step.

Built-in (zero-dep) adapters

• InMemoryStorage — Stores data in-memory for the current session. Ideal for testing, CI, and debug builds.

Platform adapters (implement yourself — it's ~10 lines)

Zenify deliberately does NOT bundle shared_preferences, hive, sqflite, etc. as dependencies. Instead, implement ZenStorage yourself:

SharedPreferences (encodes map → JSON string)

import 'dart:convert';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:zenify/zenify.dart';

class SharedPreferencesStorage implements ZenStorage {
  SharedPreferences? _prefs;
  Future<SharedPreferences> get _instance async =>
      _prefs ??= await SharedPreferences.getInstance();

  @override
  Future<void> write(String key, Map<String, dynamic> json) async =>
      (await _instance).setString(key, jsonEncode(json));

  @override
  Future<Map<String, dynamic>?> read(String key) async {
    final raw = (await _instance).getString(key);
    return raw != null ? jsonDecode(raw) as Map<String, dynamic> : null;
  }

  @override
  Future<void> delete(String key) async =>
      (await _instance).remove(key);
}

SQLite / Drift (stores map natively — no JSON encoding needed)

import 'package:zenify/zenify.dart';

class DriftStorage implements ZenStorage {
  final AppDatabase _db;
  DriftStorage(this._db);

  @override
  Future<void> write(String key, Map<String, dynamic> json) =>
      _db.zenCache.insertOrReplace(ZenCacheCompanion(
        key: Value(key),
        data: Value(jsonEncode(json['data'])),
        timestamp: Value(json['timestamp'] as int),
      ));

  @override
  Future<Map<String, dynamic>?> read(String key) async {
    final row = await _db.zenCache
        .select().where((t) => t.key.equals(key)).getSingleOrNull();
    if (row == null) return null;
    return {'data': jsonDecode(row.data), 'timestamp': row.timestamp, 'version': 1};
  }

  @override
  Future<void> delete(String key) =>
      (_db.zenCache.delete()..where((t) => t.key.equals(key))).go();
}

// toMap()/fromMap() plug in directly — no JSON encoding needed:
ZenQueryConfig<User>(
  persist: true,
  storage: DriftStorage(db),
  toJson: (user) => user.toMap(),
  fromJson: User.fromMap,
)

See also example/zen_offline/lib/storage.dart for a full production example.

Classes

InMemoryStorage

An in-memory ZenStorage implementation.

ZenStorage

Interface for persisting query data.