Buffer and streams relationship in Node.js - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a Buffer from a string.

Node.js

const buf = Buffer.[1]('Hello');

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

Afrom

Balloc

Cwrite

Dslice

Attempts:

3 left

💡 Hint

Common Mistakes

Using Buffer.alloc instead of Buffer.from

Trying to use Buffer.write directly

The Buffer.from() method creates a new Buffer containing the given string.

2fill in blank

medium

Complete the code to read data from a readable stream into a Buffer.

Node.js

stream.on('data', chunk => {
  const buf = Buffer.[1](chunk);
});

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Aalloc

Bslice

Cconcat

Dfrom

Attempts:

3 left

💡 Hint

Common Mistakes

Using Buffer.alloc which creates empty buffer

Trying to use Buffer.concat on single chunk

Each chunk from a stream is a Buffer or can be converted to one using Buffer.from().

3fill in blank

hard

Fix the error in the code to properly concatenate multiple Buffer chunks from a stream.

Node.js

let buffers = [];
stream.on('data', chunk => {
  buffers.push(chunk);
});
stream.on('end', () => {
  const result = Buffer.[1](buffers);
});

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

Afrom

Bconcat

Calloc

Dslice

Attempts:

3 left

💡 Hint

Common Mistakes

Using Buffer.from on array of buffers

Using Buffer.alloc which creates empty buffer

Buffer.concat() combines an array of Buffers into one Buffer.

4fill in blank

hard

Fill both blanks to create a writable stream that writes Buffer data to a file.

Node.js

const fs = require('fs');
const writable = fs.createWriteStream('output.txt');
writable.[1](Buffer.[2]('Data to write'));

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Awrite

Bfrom

Calloc

Dend

Attempts:

3 left

💡 Hint

Common Mistakes

Using Buffer.alloc instead of Buffer.from

Using end instead of write for sending data

The write method sends data to the writable stream, and Buffer.from() creates a Buffer from the string.

5fill in blank

hard

Fill all three blanks to read data from a readable stream, concatenate buffers, and convert to string.

Node.js

let chunks = [];
readable.[1]('data', chunk => {
  chunks.[2](chunk);
});
readable.on('end', () => {
  const buffer = Buffer.[3](chunks);
  console.log(buffer.toString());
});

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

Aon

Bpush

Cconcat

Dwrite

Attempts:

3 left

💡 Hint

Common Mistakes

Using write instead of on for event

Using alloc instead of concat

Using pop instead of push

Use on to listen for data events, push to add chunks to array, and Buffer.concat to combine buffers.