test.js

    // exchange btc to eth
    // trx - transaction from db

    let hitbtc = new ccxt.hitbtc();
    hitbtc.apiKey = ''; 
    hitbtc.secret = '';

    // check balance
    const balance = await hitbtc.fetchBalance(); 
    // balance >= trx.amountFrom check in btc

    // exchange process
    await hitbtc.paymentPostTransferToTrading({
      'amount': trx.amountFrom,
      'currency_code': 'btc',
    });

    await hitbtc.create_market_buy_order('BTC/ETH', trx.amountTo, {'trading_agreement': 'agree'});

    await hitbtc.paymentPostTransferToMain({
      'amount': trx.amountTo,
      'currency_code': 'eth',
    });

    // sending process
    await hitbtc.withdraw('eth', trx.amountTo, trx.payoutAddress)