esbuild-plugin-worker

Collect and transpile Web Workers with esbuild.

How it works

The plugin looks for new Worker('./path/to/worker.js') statements in JavaScript and TypeScript files and instructs esbuild to treat that references as entrypoints. Final output will be used to correctly update the statement.

For example, the following script:

const worker = new Worker('./path/to/worker.js');

will be transformed to:

const worker = new Worker(new URL('./path/to/worker.js', import.meta.url));

and then resolved by the @chialab/esbuild-plugin-meta-url plugin.

Please note that RNA does not generate a Worker class to instantiate like webpack does, but it will just correctly update the import reference. If you need a Worker class, you have to wrap it yourself:

const workerClass = function () {
    return new Worker('./path/to/worker.js');
};

WARNING

At the moment this plugin does not collect importScript() statements and does treat workers as modules, but we have plan to support the { type: "module" } option in the near future.

Install

npm

npm i -D @chialab/esbuild-plugin-worker

yarn

yarn add -D @chialab/esbuild-plugin-worker

pnpm

pnpm add -D @chialab/esbuild-plugin-worker

Usage

import workerPlugin from '@chialab/esbuild-plugin-worker';
import esbuild from 'esbuild';

await esbuild.build({
    plugins: [workerPlugin()],
});

You can also define a list of Worker constructors to use (default it will look for Worker and SharedWorker):

workerPlugin({ constructors: ['Worker', 'MyWorker'] });