Rename all the files in a directory with NodeJS

renameFilesInFolder.js

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

const dirPath = path.join(__dirname, './dir/relative/path');

fs.readdir(dirPath, (err, files) => {
  let x = 1;
  files.forEach((file) => {
    let oldPath = path.join(dirPath,file);
    let newPath = path.join(dirPath,`filename${x}.extension`);
    fs.renameSync(oldPath, newPath, (err) => {
      if (err) {
        console.log(err);
      }
    });
    x++;
  });
});