ChunkAssetPlugin injection breaks imported web workers

[elilambnz]

Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

Prerequisites

• I'm using the latest version of Docusaurus.
• I have tried the npm run clear or yarn clear command.
• I have tried rm -rf node_modules yarn.lock package-lock.json and re-installing packages.
• I have tried creating a repro with https://new.docusaurus.io.
• I have read the console error message carefully (if applicable).

Description

I'm developing a package that uses web workers. Everything works fine in a development build of docusaurus, however during build time the following lines are injected by ChunkAssetPlugin:

__webpack_require__.gca = function(e) {
    return e = {}[e] || e,
    __webpack_require__.p + __webpack_require__.u(e)
}

This is breaking the functionality of the web workers and produces the following error:

Uncaught ReferenceError: __webpack_require__ is not defined

Is there anyway to either prevent this behaviour for certain files, or structure my package in such a way that it is ignored by the webpack build step?

Reproducible demo

https://stackblitz.com/edit/github-1neuf8?file=src/pages/index.js

Steps to reproduce

1. Open the reproducible demo
2. Start docusaurus, there are no errors
3. Create a build and then serve docusaurus
4. The error occurs

Expected behavior

Docusaurus should ignore these files in the imported package, resulting in expected behaviour as observed with a development build.

Actual behavior

The error detailed in the description occurs. It is worth noting that the package works as expected with a clean build of Nextjs.

Your environment

• Docusaurus version used: 2.2.0

Self-service

• I'd be willing to fix this bug myself.

[Josh-Cena]

It's too hard for me to understand what's going on. A repro is appreciated—"install the npm package in question", I have zero idea how to reproduce that.

[elilambnz]

It's too hard for me to understand what's going on. A repro is appreciated—"install the npm package in question", I have zero idea how to reproduce that.

@Josh-Cena my apologies, I've amended the issue with a reproducible demo and steps to reproduce. The error can be seen in the console after running the serve command.

Please let me know if there is any more info I can provide to help address this.

[slorber]

Thanks

Your repro is using react-py, which uses Service Worker lib comlinks + pyodide:
https://github.com/elilambnz/react-py

This puts the burden on me to understand the implementation details of your lib and how Docusaurus can mess things up here (if it is even our fault in the first place? 🤷‍♂️ ).

That would be convenient to create a repro using the full setup "inlined", ie removing the react-py deps and comlinks, with a vanilla JS SW setup.

I would also suggest that you post the minimalist SW output that Docusaurus builds: what is the output, and what do you expect as an output?

Maybe you can tweak the SW output until it works and tell us what unlocks you, so that we can see how we can make the JS output you expect a reality?

I suspect adding window.__webpack_require__ = {} to the js file could make it work. __webpack_require__.gca doesn't seem to even be called in that script

---

This is likely a time-consuming bug (if it is one) for little ROI for our other users so I'm asking you to invest your time to help us here.

[elilambnz]

@slorber thanks for your feedback and suggestions to resolve this error. Unfortunately, adding the monkey patch for __webpack_require__ didn't resolve the issue. However, I did find a related issue.

Adding the following config to Docusaurus does resolve this issue, although it's not the best solution:

plugins: [
  async function disableUsedExports() {
    return {
      name: "disable-used-exports",
      configureWebpack() {
        return {
          optimization: {
            usedExports: false,
          },
        };
      },
    };
  },
]

Because this issue may not be directly related to the ChunkAssetPlugin, the title may be misleading.