buoy_storage

Buoy storage inspector for Flutter — browse and monitor shared_preferences (plus optional secure / MMKV backends) in an in-app panel that streams live to Buoy Desktop.

Part of the Buoy devtools suite. Ports @buoy-gg/storage 1:1: the same browser / events tabs, filters, storage keys, and sync protocol.

Usage

Zero-config via the umbrella:

import 'package:buoy/buoy.dart';

MaterialApp(
  builder: (context, child) =>
      BuoyDevTools(child: child ?? const SizedBox.shrink()),
);

Or register the tool directly:

import 'package:buoy_storage/buoy_storage.dart';

if (kDebugMode) registerBuoyStorage();

Live monitoring

shared_preferences has no change stream, so Buoy monitors writes two ways:

1. Owned writes — use BuoyPrefs instead of SharedPreferences for writes you want reflected instantly in the Events stream.
2. Poll/diff — while monitoring is on, Buoy snapshots and diffs all keys on a timer so writes made through any path still surface.

Secure / MMKV (optional)

No native storage deps are pulled by default. Implement a backend against your storage plugin and register it — its keys then show up in the browser (with a Secure / MMKV badge and the instance they came from) and in the desktop/MCP secure.* / mmkv.* actions:

registerBuoySecureBackend(mySecureBackend);
registerBuoyMmkvBackend(myMmkvBackend);

BuoySecureBackend.keys() returns one descriptor per key — {key, description?, keychainService?, requireAuthentication?}. Keys marked requireAuthentication are listed but never read (a read would fire a biometric prompt). Secure keys are read once when the browser opens; each read hits the keychain.

BuoyMmkvBackend.snapshot() returns one entry per instance — {id, encrypted, readOnly, entries: [{key, value, valueType}]} where valueType is string | number | boolean | buffer. MMKV is enumerable, so Buoy also polls it for changes and emits set.* / delete events. To report a write the moment it happens, call StorageEventStore.instance.recordOwnedWrite(storageType: 'mmkv', …) from your backend's setter.

See example-flutter/lib/state/demo_storage.dart for a working in-memory pair.

License

See buoy.gg. Proprietary — © Buoy.