isomorphic-ensure

Use webpack loaders seamlessly – in node as well as in the browser.

And that almost for free. Around 160 bytes is all you’ll add to the browser bundle – including boilerplate code. Measured minzipped when raw-loader and json-loader are used.

Installation

$ npm install isomorphic-ensure

Usage

1) Wire things up.

if (typeof require.ensure !== 'function') require.ensure =
  require('isomorphic-ensure')({

    // If you want to use loaders, pass them through options:
    loaders: {
      raw: require('raw-loader'),
      json: require('json-loader'),
    },

    // If you require local files, pass the current location:
    dirname: __dirname,
  })
;

2) Profit!

// …later in the same file:

require.ensure(
  ['./other-module', 'raw!./data.xml', 'tape', 'json!tape/package.json'],
  (require) => {
    // Local scripts:
    const otherModule = require('./other-module');

    // Local files via a loader:
    const data = require('raw!./data.xml');

    // Node modules:
    const tape = require('tape');

    // Node module files via a loader:
    const tapeManifest = require('json!tape/package.json');

    // Wow! It just works!
  }
);

3) If you’re using webpack, update your config.

// …
  resolve: {alias: {
    'isomorphic-ensure': 'isomorphic-ensure/mock',
    'raw-loader': 'isomorphic-ensure/mock',
    'json-loader': 'isomorphic-ensure/mock',
  }},
// …

FAQ

Isn’t require.ensure just a webpack feature?

Actually, it’s in the CommonJS spec, but node chose not to support it.

Do json-loader and raw-loader not work on the server side?

They work only if you process your server code with webpack. isomorphic-ensure works in raw JS code run directly in node. It passes a custom require function to your callback – and that function works with loaders.

How does it behave with loaders other than raw and json loaders?

Though I haven’t tested it with other loaders, we support the whole loader API. Any webpack loader should work.

Does it copies files for file/url loaders?

It does exactly the same as webpack does.

Would a build that processes server code through webpack even need this?

Nope. But sometimes that’s unnecessary overhead. I wrote this module to be able to test my UI in node. I wanted my test to be fast, so building native server code with webpack would be too slow and too complex for me.

License

MIT © Tomek Wiszniewski