app.js

var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var url = require('url');

var app = express();
var server = require('http').Server(app);

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(require('node-sass-middleware')({
  src: path.join(__dirname, 'public'),
  dest: path.join(__dirname, 'public'),
  sourceMap: true
}));
app.use(express.static(path.join(__dirname, 'public')));
app.use(express.static(path.join(__dirname, 'node_modules/quill/dist')));
app.use(express.static(path.join(__dirname, 'node_modules/quill-cursors/dist')));

app.use(require('./controllers'));

// init websockets servers
var wssShareDB = require('./helpers/wss-sharedb')(server);
var wssCursors = require('./helpers/wss-cursors')(server);

server.on('upgrade', (request, socket, head) => {
  const pathname = url.parse(request.url).pathname;

  if (pathname === '/sharedb') {
    wssShareDB.handleUpgrade(request, socket, head, (ws) => {
      wssShareDB.emit('connection', ws);
    });
  } else if (pathname === '/cursors') {
    wssCursors.handleUpgrade(request, socket, head, (ws) => {
      wssCursors.emit('connection', ws);
    });
  } else {
    socket.destroy();
  }
});

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = { app: app, server: server };