Binance Watch Ohlcv Many Symbols Continuously

'use strict';

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

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

const ohlcvsBySymbol = {};

function handleAllOHLCVs (exchange, ohlcvs, symbol, timeframe) {
    const now = exchange.iso8601 (exchange.milliseconds ());
    const lastCandle = exchange.safeValue (ohlcvs, ohlcvs.length - 1);
    const datetime = exchange.iso8601 (lastCandle[0]);
    console.log (now, datetime, symbol, timeframe, lastCandle.slice (1));
}

async function pollOHLCV (exchange, symbol, timeframe) {
    await exchange.throttle (1000); // 1000ms delay between subscriptions
    while (true) { // eslint-disable-line no-constant-condition
        try {
            const response = await exchange.watchOHLCV (symbol, timeframe);
            ohlcvsBySymbol[symbol] = response;
            handleAllOHLCVs (exchange, response, symbol, timeframe);
        } catch (e) {
            console.log (e);
        }
    }
}

async function main () {
    const exchange = new ccxt.pro.binance (); // eslint-disable-line import/no-named-as-default-member
    await exchange.loadMarkets ();
    const timeframe = '5m';

    const firstOneHundredSymbols = exchange.symbols.slice (0, 100);

    await Promise.all (firstOneHundredSymbols.map ((symbol) => pollOHLCV (exchange, symbol, timeframe)));
}

main ();