client.js

var ReconnectingWebSocket = require('reconnecting-websocket');
var sharedb = require('sharedb/lib/client');
var richText = require('rich-text');
var Quill = require('quill');
sharedb.types.register(richText.type);

// Open WebSocket connection to ShareDB server
var socket = new ReconnectingWebSocket('ws://' + window.location.host, [], {
  // ShareDB handles dropped messages, and buffering them while the socket
  // is closed has undefined behavior
  maxEnqueuedMessages: 0
});
var connection = new sharedb.Connection(socket);

// For testing reconnection
window.disconnect = function() {
  connection.close();
};
window.connect = function() {
  var socket = new ReconnectingWebSocket('ws://' + window.location.host, [], {
    // ShareDB handles dropped messages, and buffering them while the socket
    // is closed has undefined behavior
    maxEnqueuedMessages: 0
  });
  connection.bindToSocket(socket);
};

// Create local Doc instance mapped to 'examples' collection document with id 'richtext'
var doc = connection.get('examples', 'richtext');
doc.subscribe(function(err) {
  if (err) throw err;
  var quill = new Quill('#editor', {theme: 'snow'});
  quill.setContents(doc.data);
  quill.on('text-change', function(delta, oldDelta, source) {
    if (source !== 'user') return;
    doc.submitOp(delta, {source: quill});
  });
  doc.on('op', function(op, source) {
    if (source === quill) return;
    quill.updateContents(op);
  });
});