@journeyapps/powersync-sdk-react-native NPM

PowerSync SDK for React Native

PowerSync is a service and set of SDKs that keeps Postgres databases in sync with on-device SQLite databases.

This package (packages/powersync-sdk-react-native) is the PowerSync SDK for React Native clients. It is an extension of packages/powersync-sdk-common.

See a summary of features here.

Installation

Install Package

npx expo install @journeyapps/powersync-sdk-react-native

Install Peer Dependency: SQLite

This SDK currently requires @journeyapps/react-native-quick-sqlite as a peer dependency.

Install it in your app with:

npx expo install @journeyapps/react-native-quick-sqlite

Install Polyfills

This SDK can connect to a PowerSync instance via HTTP streams or Web sockets. Different polyfill configurations are required for each method.

Common Polyfills

The following polyfills are required for general use of the SDK:

base-64
react-native-get-random-values This is required for BSON and UUID generation
text-encoding Required for BSON and NDJSON streaming of sync events

npx expo install react-native-polyfill-globals base-64 react-native-get-random-values text-encoding

HTTP Streams

The following fetch polyfills are required for the React Native implementation of fetch:

react-native-fetch-api Required for live streaming of sync events
react-native-url-polyfill
web-streams-polyfill

These are listed as peer dependencies and need to be added to the React Native project

npx expo install react-native-fetch-api react-native-url-polyfill text-encoding web-streams-polyfill

Web sockets

Our web socket implementation supports binary payloads which are encoded as BSON documents.

This requires support for the Buffer interface.

Apply the Buffer polyfill

npx expo install @craftzdog/react-native-buffer

import { Buffer } from '@craftzdog/react-native-buffer';

if (typeof global.Buffer == 'undefined') {
  // @ts-ignore If using TypeScript
  global.Buffer = Buffer;
}

This library uses RSocket for reactive web socket streams which requires process.nextTick to be available. Apply a polyfill if not available.

if (typeof process.nextTick == 'undefined') {
  process.nextTick = setImmediate;
}

Enable Global Polyfills

Enable the polyfills in React Native app with

// App.js
import 'react-native-polyfill-globals/auto';

Babel Plugins: Watched Queries

Watched queries require support for Async Iterators. Expo apps currently require polyfill and Babel plugins in order to use this functionality.

npx expo install @azure/core-asynciterator-polyfill

Make sure to import the polyfill early in your application

// App.js
import '@azure/core-asynciterator-polyfill';

Install the async generator Babel plugin

pnpm add -D @babel/plugin-transform-async-generator-functions

Add the Babel plugin to your babel.config.js file

module.exports = function (api) {
 return {
   presets: [...],
   plugins: [
     // ... Other plugins
     '@babel/plugin-transform-async-generator-functions'
   ]
 };
};

Native Projects

This package uses native libraries. Create native Android and iOS projects (if not created already) by running:

npx expo run:android
# OR
npx expo run:ios

Getting Started

Our SDK reference contains everything you need to know to get started implementing PowerSync in your project.

Changelog

A changelog for this SDK is available here.

API Reference

The full API reference for this SDK can be found here.

Examples

For example projects built with PowerSync and React Native, see our Demo Apps / Example Projects gallery. Most of these projects can also be found in the demos/ directory.

Found a bug or need help?

Join our Discord server where you can browse topics from our community, ask questions, share feedback, or just say hello :)
Please open a GitHub issue when you come across a bug.
Have feedback or an idea? Submit an idea via our public roadmap or schedule a chat with someone from our product team.