Currency Convertor for Commander

currency.js

// jshint esversion: 9

async function install(pkgs) {
  pkgs = pkgs.join(' ');
  return new Promise((resolve, reject) => {
    const { exec } = require('child_process');
    exec(`npm install ${pkgs}`, (err, stdout, stderr) => {
      if (err) reject(err);
      else resolve();
    });
  });
}

/**
 * @description null
 * @param {ParamsType} params list of command parameters
 * @param {?string} commandText text message
 * @param {!object} [secrets = {}] list of secrets
 * @return {Promise<SlackBodyType>} Response body
 */
async function _command(params, commandText, secrets = {}) {
  const {
    from,
    to
  } = params;
  
  let packages = [ 'exchange-rates-api' ];
  await install(packages);
  
  const { convert } = require('exchange-rates-api');
  let amount = await convert(1, from, to); 

  return {
    response_type: 'in_channel', // or `ephemeral` for private response
    text: '1 ' + from + ' is equal to ' + amount + ' ' + to
  };
}

/**
 * @typedef {object} SlackBodyType
 * @property {string} text
 * @property {'in_channel'|'ephemeral'} [response_type]
 */

const main = async (args) => ({
  body: await _command(args.params, args.commandText, args.__secrets || {}).catch(error => ({
    response_type: 'ephemeral',
    text: `Error: ${error.message}`
  }))
});
module.exports = main;