Watch Fetch Many Exchanges Many Ordersbooks

'use strict';

import ccxt from '../../js/ccxt.js';

console.log ('CCXT Version:', ccxt.version); // eslint-disable-line import/no-named-as-default-member

async function watchOrderBook (exchange, symbol) {
   while (true) { // eslint-disable-line no-constant-condition
       try {
           const method = exchange.has.watchOrderBook ? 'watchOrderBook' : 'fetchOrderBook';
           const orderbook = await exchange[method] (symbol);
           console.log (new Date (), exchange.id, symbol, orderbook['asks'][0], orderbook['bids'][0]);
       } catch (e) {
           console.log (symbol, e);
           process.exit ();
       }
   }
}

async function watchExchange (exchangeId, symbols) {
   const exchange = new ccxt.pro[exchangeId] (); // eslint-disable-line import/no-named-as-default-member
   await exchange.loadMarkets ();
   await Promise.all (symbols.map ((symbol) => watchOrderBook (exchange, symbol)));
}

async function main () {
   const streams = {
       'ftx': [
           'BTC/USDT',
           'ETH/BTC',
       ],
       'coinex': [
           'BTC/USDT',
           'ETH/BTC',
       ],
   };

   const entries = Object.entries (streams);
   await Promise.all (entries.map (([ exchangeId, symbols ]) => watchExchange (exchangeId, symbols)));
}

main ();