Uncaught (in promise) TypeError: Cannot read properties of undefined (reading 'registerSerializer')

[EmptySpace99]

Hi everyone, I have a problem with quasar framework and thread.js and I don't know how to solve the following error: "Uncaught (in promise) TypeError: Cannot read properties of undefined (reading 'registerSerializer')"

How reproduce this error: create quasar project (with typescript support) npm install threads tiny-worker npm install -D threads-plugin

Then into your quasar.config.js: const ThreadsPlugin = require('threads-plugin');

and extend webpack in build section: extendWebpack (cfg) { cfg.plugins.push(new ThreadsPlugin()) }

Finally tried the following code from thread.js documentation in typescript section:

//App.vue
<template>
  <div><div/>
</template>
<script lang="ts">
import { spawn, Thread, Worker } from "threads"
import { Counter } from "./workers/counter"

export default {
  setup(){
    const counter = await spawn<Counter>(new Worker("./workers/counter"))
    await counter.increment()
    await Thread.terminate(counter)    

    return {}
}
</script>

//workers/counter.ts
import { expose } from "threads/worker"

let currentCount = 0

const counter = {
  getCount() {
    return currentCount
  },
  increment() {
    return ++currentCount
  },
  decrement() {
    return --currentCount
  }
}

export type Counter = typeof counter

expose(counter)

[andywer]

Hey @EmptySpace99. Can you please provide the full stack trace?

The code doesn't use registerSerializer at all, so the error must have happened somewhere "on the way".

[sylee957]

I encountered similar issue in storybook, and it is likely an import issue (even though registerSerializer is not used, I have seen it gets stuck in the comprehension of imports, because the module was somewhat undefined.) I had workaround it by require("threads") though. However, I'm working on minimal reproducible example for this.

[inlet]

any updates on this?

[sylee957]

I tried this monkey patch and it seems like working for me.

diff --git a/node_modules/threads/index.mjs b/node_modules/threads/index.mjs
index 0e7864e..2998e12 100644
--- a/node_modules/threads/index.mjs
+++ b/node_modules/threads/index.mjs
@@ -1,4 +1,4 @@
-import Threads from "./dist/index.js"
+import * as Threads from "./dist/index.js"
 
 export const registerSerializer = Threads.registerSerializer
 export const spawn = Threads.spawn
diff --git a/node_modules/threads/observable.mjs b/node_modules/threads/observable.mjs
index 52dc86f..f765af2 100644
--- a/node_modules/threads/observable.mjs
+++ b/node_modules/threads/observable.mjs
@@ -1,4 +1,4 @@
-import Observables from "./dist/observable.js"
+import * as Observables from "./dist/observable.js"
 
 export const Observable = Observables.Observable
 export const Subject = Observables.Subject
diff --git a/node_modules/threads/worker.mjs b/node_modules/threads/worker.mjs
index c53ac7d..ca822d0 100644
--- a/node_modules/threads/worker.mjs
+++ b/node_modules/threads/worker.mjs
@@ -1,4 +1,4 @@
-import WorkerContext from "./dist/worker/index.js"
+import * as WorkerContext from "./dist/worker/index.js"
 
 export const expose = WorkerContext.expose
 export const registerSerializer = WorkerContext.registerSerializer

[arietrouw]

Any update on fixing this?