Coinbasepro fetch ticker from socket with Reconnect Strategy using `ccxt` & `coinbase-pro`

Coinbasepro.js

//Modify libary file websocket.js from node_modules
//this.socket.send(JSON.stringify(message)); -> if(this.socket) this.socket.send(JSON.stringify(message));


/**
 * Created by Azhar on 21-05-2019.
 */

const ccxt = require('ccxt');
let MarketSummaries = new Map();
let tickerCounter = 0;
let coinbasepro = new ccxt['coinbasepro'];
let websocket;
let lastAlive = new Date().getTime();

coinbasepro.fetchMarkets()
    .then((marketinfo) => {
      //console.log(market);
      console.log('coinbasepro fetch market for socket success');
      initSocket(marketinfo);
    })
    .catch(err => {
      //todo handle failure
      console.error('error in initializing coinbasepro', err);
    });

function initSocket(marketinfo) {
  marketids = marketinfo.map(pair => {
      return pair.id;
  });

  websocket = new (require('coinbase-pro')).WebsocketClient(
      productIDs = marketids,
      websocketURI = 'wss://ws-feed.pro.coinbase.com',
      auth = null,
      { channels: ['heartbeat', 'ticker'] }
  );

  websocket.on('open', () => {
    console.log('coinbasepro socket open') // socket connected
  });

  websocket.on('message', data => {
    /* work with data */
     lastAlive = new Date().getTime();
     handleTicker(data);
  });
  websocket.on('error', err => {
    /* handle error */
    console.warn('coinbasepro socket error:', err) // socket error
  });
  websocket.on('close', () => {
    /* ... */
    console.error('coinbasepro socket close') // socket closed
  });

}

//Monitor heartbeat and reconnect if needed
setInterval(()=> {
   const timeDiff = ((new Date().getTime() - lastAlive)) / 1000; //Secs
   if(timeDiff > 10) { //If greater than 10 Secs
     //reconnect

     if(websocket.socket) {
       websocket.socket.close();
       websocket.socket = null;
     }
     websocket.connect();
     console.warn('coinbasepro got disconnected. Trying to reconnect since '+timeDiff+' Secs');
   }
}, 5000);

/**
 * format - { type: 'ticker',
  sequence: 8011783,
  product_id: 'XRP-BTC',
  price: '0.00007207',
  open_24h: '0.00006783',
  volume_24h: '2311434.00000000',
  low_24h: '0.00006700',
  high_24h: '0.00008110',
  volume_30d: '31099622',
  best_bid: '0.00007203',
  best_ask: '0.00007214' }
 */
function handleTicker(data) {
  if(!data || data.type !== 'ticker') return;
  tickerCounter++;
  if(tickerCounter % 10 === 0) {
      console.log(`coinbasepro tickers update counter: ${tickerCounter}`);
  }

  const dataName = data.product_id.split('-');
  let symbol = dataName[0] + '/' + dataName[1];
  MarketSummaries[symbol] = {
    bid: parseFloat(data.best_bid),
    ask: parseFloat(data.best_ask),
    last: parseFloat(data.price),
    timestamp: new Date().toISOString()
  };
}

module.exports = MarketSummaries;