Creating worker threads in Node.js - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the Worker class from the worker_threads module.

Node.js

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

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

AThread

BWorker

CWorkerThread

DThreadWorker

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect class names like Thread or WorkerThread.

Trying to import the whole module without destructuring.

The Worker class is imported from the worker_threads module to create new worker threads.

2fill in blank

medium

Complete the code to create a new worker thread running the script 'worker.js'.

Node.js

const worker = new Worker('[1]');

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

A'./worker'

B'worker.js'

C'./worker.js'

D'worker'

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting the './' prefix causing module not found errors.

Leaving out the '.js' extension.

The path to the worker script should be a relative path string like './worker.js' to correctly locate the file.

3fill in blank

hard

Fix the error in the code to listen for messages from the worker.

Node.js

worker.on('[1]', (msg) => {
  console.log('Message from worker:', msg);
});

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

Amessage

Bmsg

Cdata

Dsend

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect event names like 'msg' or 'data'.

Trying to listen for 'send' event which does not exist.

The event name to listen for messages from a worker is 'message'.

4fill in blank

hard

Fill both blanks to send a message 'Hello' to the worker and listen for its response.

Node.js

worker.[1]('Hello');
worker.on('[2]', (response) => {
  console.log('Received:', response);
});

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

ApostMessage

Bmessage

Csend

DonMessage

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'send' instead of 'postMessage' to send data.

Listening for 'onMessage' event which does not exist.

Use postMessage to send data to the worker and listen for message events to receive data from it.

5fill in blank

hard

Fill all three blanks to create a worker, send it data, and handle errors.

Node.js

const worker = new [1]('./task.js');
worker.[2]({ task: 'compute' });
worker.on('[3]', (err) => {
  console.error('Worker error:', err);
});

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

AWorker

BpostMessage

Cerror

DThread

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Thread' instead of 'Worker' to create the worker.

Using 'send' instead of 'postMessage' to send data.

Listening for 'err' event instead of 'error'.

Create a Worker instance, use postMessage to send data, and listen for error events to catch errors.