IndexedDB

import { createIndexDbAdapter, createNusmStore } from "nusm";

const activity = createNusmStore(
  { entries: [] as Array<{ id: string; message: string }> },
  {
    adapter: createIndexDbAdapter({
      dbName: "acme-app",
      storeName: "state",
    }),
    persist: { strategy: "entire" },
    storeId: "activity",
  },
);

await activity.ready;

OptionsCopy Anchor Link

interface IndexDbAdapterOptions {
  dbName?: string;
  storeName?: string;
  version?: number;
  serialize?: (value: unknown) => string;
  deserialize?: (raw: string) => unknown;
  pacer?: NusmPacerConfig;
}

BehaviorCopy Anchor Link

The adapter creates its object store during the database upgrade event when needed. Reads, writes, removes, key enumeration, and clear operations run through IndexedDB transactions.

Physical keys follow the standard nusm layout:

nusm:<storeId>:entire
nusm:<storeId>:slice:<sliceKey>

When to choose itCopy Anchor Link

IndexedDB is a good fit when state is too substantial for synchronous Web Storage, writes are naturally asynchronous, or you want a dedicated object store boundary.

Configure Authenticated synchronization with an HMAC source to share IndexedDB-backed state. Remote values pass the receiving store validator before being written into its IndexedDB store.

Browser boundaryCopy Anchor Link

createIndexDbAdapter requires the global indexedDB API and throws outside a compatible browser environment. Construct it on the client. Tests can provide an IndexedDB-compatible global such as fake-indexeddb before adapter creation.