rollem

Roll up multiple ES6 bundles at once

Why?

Rollup is great, but does not handle multiple bundles right out of the box. Rollem just handles a simple case

// rollem.config.js
module.exports = [{
  entry: 'src/foo.js',
  dest: 'dist/foo.js'
}, {
  entry: 'src/bar.js',
  dest: 'dist/bar.js'
}]

Which builds two bundles dist/foo.js and dist/bar.js when you run rollem.

Install and use

npm install -D rollem
// create rollem.config.js shown above
// then set script command
"build": "rollem"

You can pass --watch option in the command to enable simple bundle rebuild on changes.

You can pass -c <filename> to specify a different config file.

rollem.config.js

Almost the same syntax as rollup.config.js but exports an Array. You can use JavaScript module to create the list of configs dynamically.

// rollem.config.js with ES5
const configs = glob.sync('src/**/*-spec.js').map(toConfig)
module.exports = configs

// rollem.config.js with ES6
export default [{
  entry: 'src/foo.js',
  dest: 'dist/foo.js'
}, {
  entry: 'src/child-folder/bar.js',
  dest: 'dist/bar.js',
  format: 'umd',
  moduleName: 'bar',
  sourceMap: 'inline'
}]

API

In addition to the simple command line, you can use rollem via its module API. It exports a single function

const rollem = require('rollem')
rollem(configs, options)

• configs - simple Array of Rollup config objects
• options - object with options, right now only watch property is supported.

The rollem(configs, options) returns a Promise, resolved after the bundles have been built. The promise is resolved with the list of built files.

If you run rollem(configs, {watch: true}) then the resolved Promise will give you an event emitter. Every time there is a file change, you first will get "changed" event, and after the bundles have been built you will get an event "rolled".

rollem(configs, {watch: true})
  .then((ee) => {
    ee.on('changed', () => console.log('bundles will be rebuilt'))
    ee.on('rolled', () => console.log('new bundles have been built'))
  })

The rollem in watch mode tries to determine the folder to watch from the source files. Because it only knows about the top level entry file, it just grabs and watches the top parent folders. For example, if entries specify src/entry.js, src/foo/bar.js then the top parent folder watched will be src.

Debug

If something is wrong, run the tool with debug output enabled

DEBUG=rollem rollem

Small print

Author: Gleb Bahmutov <[e-mail]> © 2016

• @bahmutov
• glebbahmutov.com
• blog

License: MIT - do anything with the code, but don't blame me if it does not work.

Support: if you find any problems with this module, email / tweet / open issue on Github

MIT License

Copyright (c) 2016 Gleb Bahmutov <[e-mail]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.