Loading modules from NPM at runtime

dl_require_template.js

dl_require(['beauty', 'moment']).then(_modules => {
  /* Demo data end */
  var beauty = _modules.beauty;
  var moment = _modules.moment;
  beauty.beautifyConsole();
  console.log('log:', 'you can put your code here');
  console.info('info:', moment().format("dddd, MMMM Do YYYY, h:mm:ss a"));
  /* Demo data end */
});


function dl_require(module_names) {
  return new Promise(function (resolve, reject) {
    var modules = {};
    var missing_modules = [];
    module_names.forEach(module_name => {
      try {
        modules[module_name] = require(module_name);
      }
      catch (ex) {
        missing_modules.push(module_name)
      }
    });
    if (missing_modules.length) {
      var child = require('child_process').exec('npm i ' + missing_modules.join(' '), { stdio: [0, 1, 2] }, function (err, stdout, stderr) {
        if (err)
          throw (stderr);
        missing_modules.forEach(module_name => {
          modules[module_name] = require(module_name);
        });
        resolve(modules);
      });
      child.stdout.on('data', function (data) {
        console.log(data.toString());
      });
    }
    else {
      resolve(modules);
    }
  });
}