# localForage — Offline Storage That Just Works

> An asynchronous JavaScript library that wraps IndexedDB, WebSQL, and localStorage behind a simple localStorage-like API for reliable offline storage.

## Install

Save as a script file and run:

# localForage — Offline Storage That Just Works

## Quick Use
```bash
npm install localforage
```
```js
import localforage from 'localforage';

await localforage.setItem('user', { name: 'Ada', score: 42 });
const user = await localforage.getItem('user');
console.log(user.name); // Ada
```

## Introduction
localForage provides a simple key-value API modeled after localStorage but backed by IndexedDB or WebSQL for much higher storage limits and non-blocking reads and writes. It lets developers store blobs, typed arrays, and complex objects without serialization boilerplate, falling back gracefully across browsers.

## What localForage Does
- Stores and retrieves JavaScript objects, blobs, and typed arrays with a promise-based API
- Automatically selects the best storage backend: IndexedDB, WebSQL, or localStorage
- Supports multiple named database instances for data isolation
- Provides iteration over all stored keys with a forEach method
- Works in all modern browsers and older ones back to IE 10

## Architecture Overview
localForage wraps multiple browser storage engines behind a unified asynchronous interface. On initialization, it probes for the best available driver in order: IndexedDB, WebSQL, then localStorage. Each driver implements the same internal contract (getItem, setItem, removeItem, keys, iterate). Values are serialized only when falling back to localStorage; IndexedDB and WebSQL store structured clones natively, preserving types like Blob and ArrayBuffer without manual conversion.

## Setup & Configuration
- Install from npm or include via CDN for direct browser use
- Import and use immediately; no configuration required for defaults
- Create isolated instances with `localforage.createInstance({ name: 'myDB' })`
- Force a specific driver with `localforage.setDriver(localforage.INDEXEDDB)`
- Configure database name, store name, and version via `localforage.config()`

## Key Features
- Promise and callback API for flexible async patterns
- Stores binary data (Blob, File, ArrayBuffer) natively in IndexedDB
- Automatic driver selection with transparent fallback
- Multiple independent instances per application
- Tiny footprint (under 10 KB minified and gzipped)

## Comparison with Similar Tools
- **idb** — thin IndexedDB wrapper with no fallback; localForage adds multi-driver support and a simpler API
- **Dexie.js** — full IndexedDB ORM with queries and indexes; localForage is simpler for basic key-value needs
- **PouchDB** — document database with CouchDB sync; heavier than localForage for simple caching
- **localStorage (native)** — synchronous and limited to 5 MB of strings; localForage removes both constraints

## FAQ
**Q: How much data can localForage store?**
A: When using IndexedDB (the default), browsers typically allow hundreds of megabytes. The exact limit depends on the browser and available disk space.

**Q: Does localForage work in Web Workers?**
A: Yes. IndexedDB is available in workers, so localForage functions normally in that context.

**Q: Can I use localForage with React or Vue?**
A: Yes. It is framework-agnostic and works anywhere JavaScript runs in the browser.

**Q: Is the data encrypted?**
A: No. localForage stores data as-is in the browser's storage. For encryption, wrap values with a library like crypto-js before storing.

## Sources
- https://github.com/localForage/localForage
- https://localforage.github.io/localForage/

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Source: https://tokrepo.com/en/workflows/asset-a8deb7a3
Author: Script Depot