[Solved] This code tries to use workers but has an error: const { Worker } = require('worker_threads'); const worker = new Worker('./worker.js'); worker.... What is the likely problem here? | Node.js

Node.js - Worker Threads

This code tries to use workers but has an error:

const { Worker } = require('worker_threads');
const worker = new Worker('./worker.js');
worker.on('message', (msg) => console.log(msg));
worker.postMessage('start');

What is the likely problem here?

AThe worker script must use parentPort to receive messages

BYou cannot send messages to workers using postMessage

CWorker constructor requires a function, not a file path

DMissing cluster module import

Step-by-Step Solution

Solution:

Step 1: Check worker communication setup
Workers communicate via message passing. The worker script must listen on parentPort to receive messages.
Step 2: Identify missing code in worker.js
If worker.js does not use parentPort.on('message'), it cannot handle messages sent by postMessage, causing no response or error.
Final Answer:
The worker script must use parentPort to receive messages -> Option A
Quick Check:
Worker script needs parentPort listener [OK]

Quick Trick: Worker script must listen on parentPort for messages [OK]

Common Mistakes:

Thinking postMessage is invalid for workers
Confusing worker_threads with cluster usage
Assuming Worker constructor takes a function directly

Master "Worker Threads" in Node.js

9 interactive learning modes - each teaches the same concept differently

Learn Why Deep Visual Try Challenge Project Recall Perf

More Node.js Quizzes

This code tries to use workers but has an error:

Step 1: Check worker communication setup

Step 2: Identify missing code in worker.js

Final Answer:

Quick Check:

Want More Practice?