configwire #

Pure-Dart ConfigWire client (fetch, cache, typed getters, realtime). Works on Dart VM and Flutter from this single package — no Flutter facade needed. Requires Dart SDK >=3.12.0.

Server wire details live in the server repo: https://github.com/configwire/configwire/blob/main/docs/CONTRACT.md.

Install #

dart pub add configwire

Or pin it in your pubspec.yaml:

dependencies:
  configwire: ^0.0.1

Git fallback (before/while pub.flutter-io.cn review is pending):

dependencies:
  configwire:
    git:
      url: https://github.com/configwire/dart.git
      ref: main

Then dart pub get (flutter pub get on Flutter).

Usage #

Omit store: for the default session-only in-memory cache (MemoryCacheStore). For disk persistence, implement the CacheStore seam and pass it as store::

import 'dart:convert';
import 'dart:io';

import 'package:configwire/configwire.dart';

class JsonFileStore implements CacheStore {
  JsonFileStore(this.file);
  final File file;
  @override
  Future<CacheData?> load() async {
    try {
      final decoded = jsonDecode(await file.readAsString());
      if (decoded is! Map) return null;
      return CacheData.fromJson(Map<String, Object?>.from(decoded));
    } catch (_) {
      return null; // miss/corruption: caller falls back to defaults
    }
  }
  @override
  Future<void> save(CacheData data) async {
    await file.parent.create(recursive: true);
    await file.writeAsString(jsonEncode(data.toJson()));
  }
}

final cw = ConfigWire(
  apiKey: 'YOUR_SDK_KEY', // sent as X-ConfigWire-Key, never printed
  env: 'dev',
  baseUrl: 'http://127.0.0.1:8090',
  defaults: {'launch_flag': false},
  // Omit `store:` for the session-only memory cache.
  // store: JsonFileStore(File('.configwire-cache/cache_dev.json')),
);
await cw.ensureInitialized();
await cw.fetchAndActivate();
final on = cw.getBool('launch_flag');
await cw.dispose();

Realtime: cw.connectRealtime() opens SSE plus a 15min poll fallback, so freshness is at most pollInterval plus one fetch on every path.

See example/main.dart for a runnable demo.

Cache #

Persistence is bring-your-own via the CacheStore seam: implement load()/save() over the backend of your choice (JSON file, shared_preferences, Isar, or any disk store you prefer). MemoryCacheStore is session-only (no disk) and is the default when store: is omitted.

Values persist as cleartext JSON: never put tokens, secrets, or PII into flag values or defaults (on Web the store is additionally readable by site JS, so the XSS framing applies). Blocked storage (private mode, denied quota) degrades to load-null/save-noop — the client keeps serving defaults plus server fetches and never throws. Web fetches need server CORS allowing the app origin.

Run the browser smoke suite with dart test -p chrome test/chrome_smoke_test.dart (needs Chrome). The smoke suite runs on the session-only memory store with a mock HTTP client, so no disk or backend setup is needed.

License #

MIT — Copyright (c) 2026 Lam Thanh Nhan. See LICENSE.