@plim/storage

Durable persistence primitives for Plim documents. @plim/storage is framework-agnostic: it stores serialized Snapshot strings behind a small adapter interface, then composes those adapters with debounced autosave.

Autosave to localStorage

import { createAutosave, createLocalStorageAdapter } from '@plim/storage';

const autosave = createAutosave({
editor,
adapter: createLocalStorageAdapter(),
key: 'doc',
});

await autosave.load();

Autosave listens to editor.onTransaction, waits for the debounce window, then saves new Snapshot(editor).serialize(). Use saveNow() to bypass the debounce, flush() to save pending work, load() to restore a saved snapshot, and stop() to unsubscribe.

Storage adapters

Every adapter is string-in/string-out. Values are serialized Plim snapshots.

interface StorageAdapter {
load(key: string): Promise<string | null>;
save(key: string, value: string): Promise<void>;
remove(key: string): Promise<void>;
keys?(): Promise<string[]>;
}

Built-ins:

• createMemoryAdapter() for tests, servers, and SSR-safe ephemeral storage.
• createLocalStorageAdapter({ storage, prefix }) for browser localStorage, with injectable storage for tests.
• createIndexedDBAdapter({ dbName, storeName, indexedDB }) for async browser persistence, with injectable IndexedDB for tests.
• createTransportAdapter(transport, { timeoutMs, requestId }) for saving through a remote peer.

Transport/server-document pattern

createTransportAdapter uses @plim/transports (send, onMessage, close) to request persistence from another endpoint. The client sends:

type StorageTransportMessage =
| { type: 'save'; key: string; value: string }
| { type: 'remove'; key: string }
| { type: 'load'; key: string; id: string }
| { type: 'loaded'; key: string; id: string; value: string | null };

A server peer listens for save, remove, and load. For each load, reply with loaded using the same id and key; the adapter ignores unrelated replies and rejects if the timeout elapses.