⚡️ RNAsyncStorageLevel

This is anabstract-levelimplementation ofAsyncStoragefor React Native using TypeScript.

It was tested with Expo SDK 48 for iOS & Android.

❗️❗️❗️ Moved to@hyphen-id/rn-async-storage-level❗️❗️❗️

🔥 Prerequisites

AsyncStoragehas to be installed, and development builds have to be created:

yarn add @react-native-async-storage/async-storage
yarn expo run:ios
yarn expo run:android

💿 Installation

yarn add @pax-k/rn-async-storage-level

🏋️ Usage

✅ With promises (prefered way)

import { RNAsyncStorageLevel } from '@pax-k/rn-async-storage-level'
import AsyncStorage from '@react-native-async-storage/async-storage'

async function withAsync() {
try {
// create a new db
const db = new RNAsyncStorageLevel(AsyncStorage, 'my-db-1')

// listen for 'put' events
db.on('put', (key, value) => {
console.log('event: put', key, value)
})

// listen for 'del' events
db.on('del', (key) => {
console.log('event: del', key)
})

// listen for 'clear' events
db.on('clear', () => {
console.log('event: clear')
})

// write some data
await db.put('key1', 'value1')
await db.put('key2', 'value2')

// get the value of one key
console.log(await db.get('key1'))

// get the values of multiple keys
console.log(await db.getMany(['key1', 'key2']))

// get all keys
console.log(await db.keys().all())

// get all values
console.log(await db.values().all())

// get all entries
console.log(await db.iterator().all())

// delete a key
await db.del('key1')

// clear db
await db.clear()
} catch (error) {
console.error(error)
}
}

🌝 With callbacks (prefer promises)

import { RNAsyncStorageLevel } from '@pax-k/rn-async-storage-level'
import AsyncStorage from '@react-native-async-storage/async-storage'

async function withCallbacks() {
// create a new db
const db = new RNAsyncStorageLevel(AsyncStorage, 'my-db-1')

// listen for 'put' events
db.on('put', (key, value) => {
console.log('event: put', key, value)
})

// listen for 'del' events
db.on('del', (key) => {
console.log('event: del', key)
})

// listen for 'clear' events
db.on('clear', () => {
console.log('event: clear')
})

// write some data
db.put('key1', 'value1', (err) => {
if (err) console.error(err)
console.log('put callback')
})

db.put('key2', 'value2', (err) => {
if (err) console.error(err)
console.log('put callback')
})

// get the value of one key
db.get('key1', (err, result) => {
if (err) console.error(err)
console.log('get callback', result)
})

// get the values of multiple keys
db.getMany(['key1', 'key2'], (err, result) => {
if (err) console.error(err)
console.log('getMany callback', result)
})

// get all keys
db.keys().all((err, result) => {
if (err) console.error(err)
console.log('keys callback', result)
})

// get all values
db.values().all((err, result) => {
if (err) console.error(err)
console.log('values callback', result)
})

// get all entries
db.iterator().all((err, result) => {
if (err) console.error(err)
console.log('iterator callback', result)
})

// delete a key
db.del('key1', (err) => {
if (err) console.error(err)
console.log('del callback')
})

// clear db
db.clear((err) => {
if (err) console.error(err)
console.log('clear callback')
})
}

🙋‍♂️ FAQ

👉🏻 Why build this

There was no modern and actively maintainedabstract-levelcompatible storage for React Native.

👉🏻 Why this works

abstract-leveluses NodeJS native functions which won't work in a browser (or in the Hermes JS engine for React Native). At build time,parcelpollyfillssome of the native functions, but missestext-encoding.This is injected bybuild.sh,thenbrowserifybundles everything together into a 100% browser compatible module.

Apart from bundling, it is important to haveAsyncStoragemodule installed in the consumer app, for it to referece the correct bindings. This is why it needs to be refereced from the app:

const db = new RNAsyncStorageLevel(AsyncStorage, 'my-db-1')

🚧 Limitations

• Known storage limits
• a value's type is limited tostring | number | boolean | null | undefined
• no support forsnapshots, keyIterator, valueIterator, iteratorNextv, streams, seek, batch
• without support for snapshots, isolation of transactions is instead guaranteed by using await/promises (as they are sequential), as opposed to callbacks that usequeueMicrotask

👷 TODO

• support forkeyIterator, valueIterator, iteratorNextv, batchoperations
• support forUint8Arrayas value type (for storing files as blobs)
• caching + invalidation
• add tests

🌈 Shouts 👏🏻

ToHyphenfor sponsoring this effort and toTBDfor powering the next wave of private & decentralised apps.

👋 Contribute

Running the project locally

git clone https://github /pax-k/rn-async-storage-level && cd rn-async-storage-level
yarn
cd expo-demo && yarn && yarn expo start:ios
cd../ && yarn watch