y-webxdc

Webxdc provider for Yjs

The WebxdcProvider turns apps using yjs into production-ready webxdc apps. Webxdc apps can be shared in a chat with messengers like Delta Chat and Cheogram, sharing all application state with chat members via yjs.

WebxdcProvider supports:

• immediate receiving of yjs changes from chat peers

• autosaving: saving yjs changes periodically to chat peers

• manual saving: call provider.syncToChatPeers() for causing immediate saving (it's fine to mix manual and autosaving).

• setting of document, summary and chat-message info which is the metadata shown in a chat (see below screenshots).

• reliably saving any pending yjs changes when the app window closes, on all webxdc-supporting platforms.

• resending entire state to force consistency over unreliable messanger delivery (resendAllUpdates).

Setup

Install

npm i y-webxdc

Client code

import * as Y from 'yjs'
import { WebxdcProvider } from 'y-webxdc'

// provided by messengers or webxdc-dev tool 
// see https://docs.webxdc.org/spec.html
const webxdc = window.webxdc;  

const ydoc = new Y.Doc()
const yarray = ydoc.get('array', Y.Array)
const provider = new WebxdcProvider({
    webxdc,
    ydoc,
    autosaveInterval: 10*1000,
    getEditInfo: () => {
        const document = 'webxdc yjs provider';
        const summary = `Last edit: ${webxdc.selfName}`;
        const startinfo = `${webxdc.selfName} editing ${document}`;
        return {document, summary, startinfo}; 
    },
    resendAllUpdates: false
});

See the following example for the meaning of document, summary and startinfo as returned by the getEditInfo callback passed into the provider.

Example

The webxdc editor uses y-webxdc to implement a collaborative editor.

Development

Test

Run code-style checks with the following command (basically same as npm run check):

npm test

Code Style

Code style is checked and fixed by eslint, run:

npm run check
npm run fix

to perform checks or apply suggested fixes. Note that npm test will automatically check code style.