Passing data to workers in Node.js - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a new worker thread.

Node.js

const { Worker } = require('worker_threads');
const worker = new Worker([1]);

Drag options to blanks, or click blank then click option'

A'./worker.js'

Bworker.js

Cnew Worker()

Drequire('worker_threads')

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around the file path.

Passing the module instead of the path string.

You must pass the path to the worker script as a string to the Worker constructor.

2fill in blank

medium

Complete the code to send data to the worker thread.

Node.js

worker.postMessage([1]);

Drag options to blanks, or click blank then click option'

Adata

B'data'

CworkerData

Dmessage

Attempts:

3 left

💡 Hint

Common Mistakes

Passing a string literal instead of the data variable.

Using undefined variable names.

You send the actual data object or value to the worker using postMessage.

3fill in blank

hard

Fix the error in receiving data inside the worker thread.

Node.js

const { parentPort } = require('worker_threads');
parentPort.on('message', ([1]) => {
  console.log('Received:', data);
});

Drag options to blanks, or click blank then click option'

Amsg

Bmessage

Cevent

Ddata

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different parameter name than the one logged.

Not defining the parameter at all.

The parameter name must match the variable used inside the function to access the data.

4fill in blank

hard

Fill both blanks to pass initial data to the worker using workerData.

Node.js

const { Worker, [1] } = require('worker_threads');
const worker = new Worker('./worker.js', { [2]: { value: 42 } });

Drag options to blanks, or click blank then click option'

AworkerData

BparentPort

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'parentPort' instead of 'workerData'.

Not passing the data inside the options object.

You import 'workerData' and pass it as an option to the Worker constructor to send initial data.

5fill in blank

hard

Fill all three blanks to create a worker that receives initial data and listens for messages.

Node.js

const { Worker, [1] } = require('worker_threads');

// In main thread
const worker = new Worker('./worker.js', { [2]: { name: 'Alice' } });

// In worker.js
const { parentPort, [3] } = require('worker_threads');
console.log('Name:', workerData.name);
parentPort.on('message', (msg) => {
  console.log('Message:', msg);
});

Drag options to blanks, or click blank then click option'

AworkerData

DparentPort

Attempts:

3 left

💡 Hint

Common Mistakes

Not importing workerData in the worker file.

Confusing parentPort and workerData.

Not passing workerData in the Worker constructor options.

You import and use 'workerData' to access initial data in the worker, and 'parentPort' to listen for messages.