files.js

const fs = require("fs");
const path = require("path");

function getFilesFromDir(dir, fileTypes) {
    const filesToReturn = [];
    function walkDir(currentPath) {
      const files = fs.readdirSync(currentPath);
      for (let i in files) {
        const curFile = path.join(currentPath, files[i]);      
        if (fs.statSync(curFile).isFile() && fileTypes.indexOf(path.extname(curFile)) != -1) {
          filesToReturn.push(curFile);
        } else if (fs.statSync(curFile).isDirectory()) {
          walkDir(curFile);
        }
      }
    };
    walkDir(dir);
    return filesToReturn; 
}

module.exports = getFilesFromDir;