Error Handling

// @NO_AUTO_TRANSPILE
import ccxt from '../../js/ccxt.js';
const verbose = process.argv.includes('--verbose');
//-----------------------------------------------------------------------------
const printSupportedExchanges = () => console.log('Supported exchanges:', ccxt.exchanges.join(', '));
const printUsage = () => {
    console.log('Usage: node', process.argv[1], 'id'.green);
    printSupportedExchanges();
};
const run = async (id) => {
    // check if the exchange is supported by ccxt
    const exchangeFound = ccxt.exchanges.indexOf(id) > -1;
    if (exchangeFound) {
        console.log('Instantiating', id, 'exchange');
        // instantiate the exchange by id
        const exchange = new ccxt[id]({ verbose });
        // try to load markets and catch the errors if any
        try {
            await exchange.loadMarkets();
        }
        catch (e) {
            if (e instanceof ccxt.NetworkError) {
                console.log(exchange.id, 'loadMarkets failed due to a network error:', e.message);
            }
            else if (e instanceof ccxt.ExchangeError) {
                console.log(exchange.id, 'loadMarkets failed due to exchange error:', e.message);
            }
            else {
                console.log(exchange.id, 'loadMarkets failed with:', e.message);
            }
            // rethrow the error "higher up" the call chain
            throw e;
        }
        // try to fetch a ticker and catch the errors if any
        try {
            const symbol = 'ETH/BTC';
            const response = await exchange.fetchTicker(symbol);
            console.log(response);
        }
        catch (e) {
            if (e instanceof ccxt.NetworkError) {
                console.log(exchange.id, 'fetchTicker failed due to a network error:', e.message);
            }
            else if (e instanceof ccxt.ExchangeError) {
                console.log(exchange.id, 'fetchTicker failed due to exchange error:', e.message);
            }
            else {
                console.log(exchange.id, 'fetchTicker failed with:', e.message);
            }
            // rethrow the error "higher up" the call chain
            throw e;
        }
    }
    else {
        console.log('Exchange', id, 'not found');
        printSupportedExchanges();
    }
};
(async function main() {
    if (process.argv.length > 2) {
        let id = process.argv[2];
        await run(id);
    }
    else {
        printUsage();
    }
    process.exit();
})();