Get all files from within a given directory using Node.js

getFIles.js

// To log the results:
//
// getFiles(__dirname, { ignore: ['node_modules'] })
//   .then(files => console.log(
//     files
//       .flat(Infinity)
//       .filter(( Oo) => (Oo ))
//   ));

// Available options:
//  - ignore[] => circuit break at given files / directories
//  - only[]   => only include files matching filenames in this list
//  - relative => emit paths relative to the inital directory
//  - verbose  => log errors and skipped files

const fs = require("fs");
const path = require("path");
const { promisify } = require("util");

const readdir = promisify(fs.readdir);
const getStat = promisify(fs.stat);

module.exports = getFiles;

async function getFiles(dir, o, initDirLength) {
	dir || (dir = __dirname);
	o || (o = {});
	initDirLength || (initDirLength = dir.length);

	try {
		return await Promise.all(
			(await readdir(dir)).map(async (file) => {
				if (!file) {
					if (o.verbose) {
						console.log(`Missing file path under: ${dir}`);
					}
					return undefined;
				}

				const filePath = path.resolve(dir, file);
				if (
					o.ignore
					&& o.ignore.includes(file)
				) {
					if (o.verbose) {
						console.log(`Ignored: ${filePath}`);
					}
					return undefined;
				}

				if (
					!o.includeHidden
					&& file.startsWith(".")
				) {
					if (o.verbose) {
						console.log(`Ignored hidden file: ${filePath}`);
					}
					return undefined;
				}

				const stat = await getStat(filePath);
				if (stat && stat.isDirectory()) {
					return await getFiles(filePath, o, initDirLength);
				}

				if (
					!o.only
					|| o.only.length === 0
					|| o.only.includes(file)
				) {
					return o.relative
						? filePath.slice(initDirLength + 1)
						: filePath;
				}
			})
		);
	} catch (error) {
		if (o.verbose) {
			console.log(`Error reading: ${dir}`);
		}
		return undefined;
	}
}