Use native approach to load web workers

[remcohaszing]

Currently to use Monaco with module bundlers such as Webpack 5, Parcel, Snowpack, or natively in ESM in a browser, one needs to use the following:

window.MonacoEnvironment = {
  getWorker(moduleId, label) {
    switch (label) {
      case 'css':
      case 'less':
      case 'scss':
        return new Worker(new URL('monaco-editor/esm/vs/language/css/css.worker', import.meta.url));
      case 'editorWorkerService':
        return new Worker(new URL('monaco-editor/esm/vs/editor/editor.worker', import.meta.url));
      case 'handlebars':
      case 'html':
      case 'razor':
        return new Worker(new URL('monaco-editor/esm/vs/language/html/html.worker', import.meta.url));
      case 'json':
        return new Worker(new URL('monaco-editor/esm/vs/language/json/json.worker', import.meta.url));
      case 'javascript':
      case 'typescript':
        return new Worker(new URL('monaco-editor/esm/vs/language/typescript/ts.worker', import.meta.url));
      case 'yaml':
        return new Worker(new URL('monaco-yaml/lib/esm/yaml.worker', import.meta.url));
      default:
        throw new Error(`Unknown label ${label}`);
    }
  },
};

All official documentation and examples on this subject are outdated.

It appears the issue of having to resolve a worker is going away. Instead of putting this burden on the user if this library, it may be better to move this to the plugins instead. I.e., a plugin could call something like:

import { registerWorker } from 'monaco-editor';

registerWorker('json', new Worker(new URL('./json.worker', import.meta.url)));

This way users don’t have to deal with workers explicitly anymore.

[jimmywarting]

I think that web workers should use new Worker(url, { type: module }) variant

[Kuinox]

I think that web workers should use new Worker(url, { type: module }) variant

Firefox doesn't support yet modules in web workers.

[jimmywarting]

Undici (aka fetch) now wants to create blobs backed up by filesystems as well when parsing multipart FormData.
New discussion is taking place here to bring life into some kind of fs.getFileBlob('some-file-path.txt') so just more reason to wanting to have this in the feature