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var esmIso = require("esm-iso")

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esm-iso v0.0.6

Isomorphic ESM Loader


An esm companion for isomorphic JS modules.

node -r esm -r esm-iso server.js


Try out the live demo with its example code.

The summary is explained in here:

import path from 'path';
import express from 'express';

// used to redirect client calls
const redirect = Object.assign(
    // import * from '/m/generic';
    // =>
    // import * from '/m/detailed/path/esm/index.js';
    'generic': 'detailed/path/esm/index.js'

const app = express();
app.use('/m/', (req, res, next) => {
  const mod = req.url.replace(/\?[\S\s]*$/, '').replace(/^\/|\/$/g, '');
  if (mod in redirect) res.redirect('/m/' + redirect[mod]);
  else next();
app.use('/m/', express.static(
  // that's it: your browser can now load any module
  path.join(__dirname, 'node_modules')

import module from '/m/generic';

You can use similar approach to also load any other module file:

<script src="/m/generic/min.js"></script>


If you want a more explicit version that uses /node_modules/ instead of /m/ as both client and server loader, you can check slash-node-modules-loader out: same loader, but with a more semantic absolute path.

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