require-from-es

This module, require-from-es, makes require, __dirname and __filename work flawlessly in ES-modules.

So you finally made the switch to using ES modules in Node.js?

Congratulations!

So you added the following in your package.json (or maybe a build tool like Vite added it...):

"type" : "module"

and you are ready to start using import and export everywhere? Those ARE good intentions.

But what about:

• old legacy code (your own and npm modules) that only works with require?
• or the convenience of requiring a json-file with require('x.json')?
• or being able to read the absolute path of your file with __filename?
• or the dir name where your file is at with __dirname?

All of this has just gone out the window...

But, fear not, just:

npm i require-from-es

And then once, at the top/start file of your application:

import 'require-from-es';

Now you can use require, __filename and __dirname anywhere in your application. No need to include something extra in each file.

More info, less important

Tested on Mac, Windows and Linux

Since requiring files requires (pun intended) a lot of juggling of file paths and those being slightly different on different OS:es, we've tested require-from-es on both Mac, Linux and Windows.

The result of our tests: It works!

How? (Only for nerds)

You're a nerd? That's good. (If not stop reading.)

So how did we do it? Well, recreating require in ES modules is done by using the function createRequire (built in to native Node.js module 'module').

The problem is that createRequire demands you to input import.meta.url as an argument. That's the same as the path to the file your code is running in.

And it is different for each file... But we are reading this path from a stack trace (carefully parsed to find the file path of the file calling require).

Then we create getters for require, __dirname and __filename in the global namespace (globalThis)... among with some other trickery to make require work in several steps down the file hierarchy :).

This means: require is created using the correct 'base path' everywhere. And you only have to import require-from-es once in your project.