Watching files for changes in Node.js - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the built-in module for watching files.

Node.js

const fs = require('[1]');

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

Afs

Bpath

Cfs-extra

Dfilewatch

Attempts:

3 left

💡 Hint

Common Mistakes

Using a non-existent module name like 'filewatch'.

Confusing 'path' module with 'fs'.

The built-in Node.js module to watch files is fs. You import it using require('fs').

2fill in blank

medium

Complete the code to watch a file named 'example.txt' for changes.

Node.js

fs.[1]('example.txt', (eventType, filename) => {
  if (filename) {
    console.log(`${filename} file changed`);
  }
});

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

AreadFile

Bwatch

Copen

DwriteFile

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'readFile' which reads file content once.

Using 'writeFile' which writes data to a file.

The fs.watch method watches for changes on a file or directory.

3fill in blank

hard

Fix the error in the callback parameter name to correctly detect the changed file.

Node.js

fs.watch('data.json', (eventType, [1]) => {
  if (filename) {
    console.log(`${filename} was modified`);
  }
});

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

AfileName

Bfile

Cfilename

Dfile_path

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'fileName' with uppercase N which is undefined.

Using a different variable name than inside the function.

The callback parameter for the filename is filename (all lowercase). It must match the variable used inside the function.

4fill in blank

hard

Fill both blanks to watch a directory named 'logs' and log the event type and filename.

Node.js

fs.[1]('logs', ([2], filename) => {
  console.log(`Event: ${eventType}, File: ${filename}`);
});

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

Awatch

Bchange

CeventType

Dopen

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'change' as a method name instead of 'watch'.

Using 'change' as a parameter name instead of 'eventType'.

Use fs.watch to watch the directory. The first callback parameter is eventType which tells what happened.

5fill in blank

hard

Fill all three blanks to watch 'config.json', check if the event is 'rename', and log the filename.

Node.js

fs.watch('config.json', ([1], [2]) => {
  if (eventType === [3]) {
    console.log(`File ${filename} was renamed.`);
  }
});

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

AeventType

Bfilename

C'rename'

D'change'

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the order of parameters.

Checking eventType against 'change' instead of 'rename'.

The callback parameters are eventType and filename. To check if the file was renamed, compare eventType to the string 'rename'.