rollup-plugin-web-worker-loader

Rollup plugin to handle Web Workers.

Can inline the worker code or emit a script file using code-splitting.
Handles Worker dependencies and can emit source maps.
Worker dependencies are added to Rollup's watch list. Supports bundling workers for Node.js environments

Getting started

yarn add rollup-plugin-web-worker-loader --dev

Add the plugin to your rollup configuration:

import webWorkerLoader from 'rollup-plugin-web-worker-loader';

export default {
    entry: 'src/index.js',
    plugins: [ 
        webWorkerLoader(/* configuration */),
    ],
    format: 'esm',
};

Bundle the worker code using the prefix web-worker: in your imports:

import DataWorker from 'web-worker:./DataWorker';

const dataWorker = new DataWorker();
dataWorker.postMessage('Hello World!');

Configuration

The plugin responds to the following configuration options:

webWorkerLoader({
    sourcemap?: boolean, // when inlined, should a source map be included in the final output. Default: false
    inline?: boolean,    // should the worker code be inlined (Base64). Default: true
    loadPath?: string    // this options is useful when the worker scripts need to be loaded from another folder. Default: ''
})

Notes

WARNING: To use code-splitting for the worker scripts, Rollup v1.9.2 or higher is required. See https://github.com/rollup/rollup/issues/2801 for more details.

The sourcemap configuration option is ignored when inline is set to false, in that case the project's sourcemap configuration is inherited.

loadPath is meant to be used in situations where code-splitting is used (inline = false) and the entry script is hosted in a different folder than the worker code.

Roadmap

• Bundle file as web worker blob
• Support for dependencies using import
• Include source map
• Configuration options to inline or code-split workers
• Provide capability checks and fallbacks
• Avoid code duplication