pouchdb-sqlite-driver-expo

Modern expo-sqlite driver for pouchdb-adapter-generic-sqlite. It uses callback-scoped exclusive transactions and passes Uint8Array values directly to Expo's native BLOB binding.

import PouchDB from "pouchdb-core";
import genericSQLitePlugin from "pouchdb-adapter-generic-sqlite";
import { createExpoSQLiteDriver } from "pouchdb-sqlite-driver-expo";

PouchDB.plugin(genericSQLitePlugin);

const database = new PouchDB("notes", {
  adapter: "generic-sqlite",
  sqlite: { driver: createExpoSQLiteDriver() },
});

The driver targets Expo SDK 57's asynchronous SQLite API. Transactions are serialized per opened connection, execute on the transaction object supplied by withExclusiveTransactionAsync, and reject executor use after the callback settles. close() waits for accepted work and is idempotent. Native Uint8Array values remain BLOBs without base64 or binary-string conversion.

Expo currently reports textKeySemantics: "nul-unsafe" conservatively across its native platforms. Embedded-NUL truncation is reproduced on Android, while PouchDB ordered keys may contain NUL separators; iOS has not yet been proven to satisfy the stricter Pouch-compatible text-key contract. The driver remains a direct implementation of the generic SQL contract and does not transform text. On first database creation, the generic core sees that capability and persists its nul-escaped storage codec; reopening continues to use that codec even if a later Expo/runtime version reports native Pouch-compatible behavior.

The optional directory, native openOptions, and logical-name-to-filename function are factory-local configuration. Custom filenames must be flat and deterministic. Any customized factory also requires a non-whitespace opaque cacheNamespace of at most 200 UTF-16 code units; equivalent namespaces must resolve every logical name to the same physical database and behavior.