router.js

const commandList = [
  { c: ['bus'], a: require('./modules/bus.js') },
];

/**
 * Executes the action indicated in the message
 */
module.exports = function router(message) {
  // If it does not start from "/", ignore
  if (message.text.indexOf('/') !== 0) {
    console.log('- Non-command received: ', message.text);
    return new Promise(() => {});
  }

  const args = message.text.slice(1).split(' ');
  const command = args[0];
  const filtered = commandList.filter(cmd => cmd.c.indexOf(command) !== -1);
  let promiseFunction;

  if (filtered.length === 1) {
    console.log('- Command: ', command);

    promiseFunction = accept => {
      filtered[0].a(...args.slice(1)).then(text => accept({
        chat_id: message.chat.id,
        text,
        options: {
          parse_mode: 'Markdown',
        },
      }));
    };
  } else {
    console.log('- Unknown command: ', command);
    promiseFunction = () => {};
  }


  return new Promise(promiseFunction);
};