Awesome
<img src='https://raw.githubusercontent.com/local-first-web/branding/main/svg/state-h.svg' width='600' alt="@localfirst/state logo" />
@localfirst/state
is an automatically replicated Redux store that gives your app offline
capabilities and secure peer-to-peer synchronization superpowers.
🚧 Work in progress
Why
Distributed, offline-first technologies are promising for a lot of reasons, but they're unfamiliar to most web application developers. This library provides offline storage and peer-to-peer synchronization capabilities, and exposes them via a familiar Redux store that can be used in a vanilla JS, React, or Electron application.
🡒 Read more
What
This library provides two services:
- Data replication & synchronization, using the Automerge library
- Persistence to a local or remote data store. You can use the provided adapters for IndexedDb or MongoDb, or provide your own.
🡒 Read more
How
Example apps
Two demo React applications are included:
<table> <tr> <td> <h4><code>todo</code></h4> <img src='images/screen.todo.png' width='400' /> <p>An implementation of TodoMVC</p> <p>To run: <code>yarn dev:todo:start</code> </p> </td> <td> <h4><code>grid</code></h4> <img src='images/screen.grid.png' width='400' /> <p>A simple table editor</p> <p>To run: <code>yarn dev:grid:start</code> </p> </td> </tr> </table>Getting started
yarn add @localfirst/state
import { StoreManager } from '@localfirst/state'
import { Provider } from 'react-redux'
const storeManager = new StoreManager({
// Pass your reducers
proxyReducer,
// Pass an initial state, just like you would for Redux
initialState: {
todoList: [],
todoMap: {},
filter: ALL,
},
})
export const Index = () => {
// Obtain a Redux store
const store = storeManager.createStore(discoveryKey)
return (
// Pass the store to your app
<Provider store={store}>
<App />
</Provider>
)
}
🡒 More on how to use @localfirst/state
in your app
Limitations
This library requires that the entire repository be present on each peer's machine. That means that it is limited to datasets that can fit comfortably within the disk space on a single computer. In 2019, that means something on the order of 1-10 GB.
Further reading
- CRDTs and the Quest for Distributed Consistency, a great talk by Martin Kleppman, the author of Automerge.
- Local-first software: You own your data, in spite of the cloud, a manifesto published by Ink & Switch, the industrial research lab created by Heroku alumni that is behind Automerge.
- A web application with no web server?
Alternatives
All of these projects are working in similar problem space, in JavaScript. All work in Node.js and the browser unless otherwise noted.
- Hypermerge is the semi-official networking and persistence stack for Automerge, based on the DAT project's Hypercore and created by the team at Ink and Switch. It's used in sample Automerge applications like Capstone and Farm. Node.js only.
- PouchDb Syncs with Apache CouchDb.
- Realm Database Acquired by MongoDB in 2019. Node.js only.
- HyperDB From the DAT Project. Showcased in a cool sample app by @jimpick: Dat Shopping List.
- GunDB Distributed graph database.