File-of-type 
A small utility that grabs and returns a promise that resolves to an array of all the file names of a specific type located in specified directory. Returns an empty array if no files were found.
Getting Started
npm i files-of-type
or
yarn add files-of-type
Use
/**
* Create an array of filenames of specific type.
* @param fileType - the file extension you are searching for
* @param filePath - the path to directory you would like to search. Defaults to __dirname
* @returns <Promise> which will eventually resolve to an array with either the files names or empty
*/
const filesOfType = require('file-of-type');
filesOfType('.js').
then(files => {
files.map(file => console.log(file));
});