Parcel: Error: Process is not defined (in web worker)

[jtenner]

🐛 bug report

Starting up a web worker in electron seems to yield

worker.4ea33c72.js:1 Uncaught ReferenceError: process is not defined
(anonymous) @ worker.4ea33c72.js:1

I see another closed issue with this error but it seems to be related to electron and web workers in the browser half of the environment.

🎛 Configuration (.babelrc, package.json, cli command)

.tsconfig

{
  "compilerOptions": {
    "sourceMap": true,
    "lib": [ "es2017", "dom" ],
    "downlevelIteration": true,
    "allowSyntheticDefaultImports": true,
    "esModuleInterop": true
  },
  "include": [
    "index.ts",
    "src/**/*.ts"
  ],
  "exclude": [
    "node_modules",
    "**/*.spec.ts"
  ]
}

Also, providing absolute paths is the only way plugins will work, because relative ones don't work.

{
  "plugins": [
    "C:\\Users\\jtenner\\Desktop\\projects\\project-revoluti0n\\babel-plugins\\script-transformer.js",
  ]
}

🤔 Expected Behavior

I guess if process isn't defined, define it. I don't know where this code is generated, but it's literally the first line of my code for the worker, and I can't get it running.

😯 Current Behavior

It's the first line of the generated worker.

💁 Possible Solution

No idea.

💻 Code Sample

The code is going to be MIT so I don't mind sharing the entry point.

import config from "../../application.config";
import { IPointClickEvent } from "../events/IPointClickEvent";
import { IPointMoveEvent } from "../events/IPointMoveEvent";
import { IWorkerEvent } from "../events/IWorkerEvent";
import { IInteractionPoint } from "../util";
import { ISprite } from "../view/Sprite";
import { IStageManagerProps, StageManager } from "./StageManager";

const props: IStageManagerProps = {
  audioContext: new AudioContext(),
  height: config.window.height,
  selector: "body",
  width: config.window.width,
};

const sm = new StageManager(props);
const worker = new Worker("../worker/index.js");

🌍 Your Environment

| Software | Version(s) |
| ---------------- | ---------- |
| Parcel | 1.9.4
| Node | 10.6.0
| npm/Yarn | 1.7.0
| Operating System | Windows
| electron | 2.0.4
| electron-builder | 20.19.2

I have no problem trying to help fix this in any way. Thanks for the help!

[DeMoorJasper]

I don't think the entrypoint is the issue, as it'll be MIT. Could you share the entire codebase? Ot at least the part with the bug?

[jtenner]

Solved the problem.

In your main.js file of your electron environment, you must enable the nodeIntegrationInWorker parameter like this:

  mainWindow = new BrowserWindow({
    width: config.window.width,
    height: config.window.height,
    webPreferences: {
      nodeIntegrationInWorker: true
    },
  });

I'm now staring down the barrel of a different problem/error which is great news!

I have the following recommendations/suggestions:

1. Can we please inform electron developers that they need to enable this option?
2. Can parcel not make the assumptions it makes about electron inside a webworker?

[DeMoorJasper]

This is out of scope of parcel however you could request electron to show a warning for that

_{Sent with GitHawk}

[jtenner]

Okay. If parcel doesn't make assumptions about the environment, can we at least put a line in our documentation where the --target=electron options appears?

Example:

For electron users who want to use workers, please enable the webPreferences: { nodeIntegrationInWorker: true } property when creating your browser window.

It would have saved me at least three hours of headaches.

[DeMoorJasper]

Feel free to open up a pr in parcel/website repo

_{Sent with GitHawk}