Why debugging skills matter in Node.js - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to print an error message when a promise is rejected.

Node.js

fetch('https://api.example.com/data')
  .then(response => response.json())
  .catch(error => console.[1](error))

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

Alog

Binfo

Cwarn

Derror

Attempts:

3 left

💡 Hint

Common Mistakes

Using console.log instead of console.error

Using console.warn which is less clear for errors

Use console.error to clearly show error messages in Node.js debugging.

2fill in blank

medium

Complete the code to catch and log errors in an async function.

Node.js

async function getData() {
  try {
    const response = await fetch('https://api.example.com/data');
    const data = await response.json();
    return data;
  } catch ([1]) {
    console.error(error);
  }
}

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

Aerr

Be

Cerror

Dexception

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different variable name than the one logged

Leaving the catch parameter empty

The catch block uses error as the variable name to hold the caught error.

3fill in blank

hard

Fix the error in the code to properly handle rejected promises.

Node.js

fetch('https://api.example.com/data')
  .then(response => response.json())
  .then(data => console.log(data))
  .[1](error => console.error(error))

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

Aerror

Bcatch

Cfail

Dreject

Attempts:

3 left

💡 Hint

Common Mistakes

Using .error or .fail which are not valid promise methods

Using .reject which is not a method

The correct method to handle rejected promises is catch.

4fill in blank

hard

Fill both blanks to create a simple error handler function.

Node.js

function handleError([1]) {
  console.[2](error.message);
}

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

Aerror

Blog

Dwarn

Attempts:

3 left

💡 Hint

Common Mistakes

Using console.log instead of console.error

Mismatching parameter and logged variable names

The function takes error as parameter and logs the message using console.error.

5fill in blank

hard

Fill all three blanks to log error details conditionally.

Node.js

function logErrorDetails([1]) {
  if (error.[2]) {
    console.[3](`Error: ${error.message}`);
  }
}

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

Aerror

Bstack

Dlog

Attempts:

3 left

💡 Hint

Common Mistakes

Using console.log instead of console.error

Checking a wrong property instead of 'stack'

The function checks if the error has a stack trace and logs the message using console.error.