rollup-split-index

Splits dependency tree into the entrypoint file and all the rest.

The purpose of this module is to use rollup to bundle all dependencies into a single file while leaving the index.js file human-readable (and human-editable). It does this with two plugins; dependenciesOnly can be used while generating dist/vendor.js and importExportToGlobal can be used while generating dist/index.js.

Install

$ yarn add rollup-split-index
# or:
$ npm install --save rollup-split-index

Usage

Your rollup.config.js file can look like this:

const config = require("./package.json");
const rollup = require("rollup");

const resolve = require("rollup-plugin-node-resolve");
const commonjs = require("rollup-plugin-commonjs");

const {
  importExportToGlobal,
  dependenciesOnly
} = require("rollup-split-index");

const inputFile = config.main; // likely index.js

module.exports = [
  {
    input: inputFile,
    plugins: [resolve(), commonjs(), dependenciesOnly()],
    output: {
      name: importExportToGlobal.referenceName,
      file: "dist/vendor.js",
      format: "iife"
    }
  },
  {
    input: inputFile,
    plugins: [resolve(), commonjs(), importExportToGlobal()],
    output: {
      file: "dist/index.js",
      format: "es"
    }
  }
];

You can then run rollup as usual with:

$ node_modules/.bin/rollup -c rollup.config.js

This will load index.js, trace its dependency tree including node_modules, and bundle all dependencies into dist/vendor.js. The vendor.js file will export a __rollup_vendor object referencing all of the imports.

In addition, this will transform index.js by rewriting es6 imports and exports to global declarations. For example:

import jQuery from 'jquery';
...
export default MyApp

becomes:

const jQuery = __rollup_vendor['jquery']
...
window.MyApp = MyApp;

You should then be able to load both files in script tags and then reference the default exported variable:

<script src="./dist/vendor.js"></script>
<script src="./dist/index.js"></script>
<script>
  console.log(window.MyApp);
</script>

License

MIT