Human-readable error messages in Rest API - Mini Project: Build & Apply

Human-readable error messages

📖 Scenario: You are building a simple REST API that returns data about books. When something goes wrong, you want to send clear, easy-to-understand error messages to the user instead of confusing technical errors.

🎯 Goal: Create a small API simulation that returns human-readable error messages for common problems like missing data or invalid input.

📋 What You'll Learn

Create a dictionary called books with three book entries and their authors

Create a variable called requested_book with the name of the book to search

Write code to check if requested_book is in books and handle errors with clear messages

Print the result or the error message

💡 Why This Matters

🌍 Real World

APIs often need to tell users what went wrong in a way they can understand, instead of showing confusing technical errors.

💼 Career

Clear error messages improve user experience and are important for developers working on web services and APIs.

1

Create the books data

Create a dictionary called books with these exact entries: '1984': 'George Orwell', 'To Kill a Mockingbird': 'Harper Lee', 'The Great Gatsby': 'F. Scott Fitzgerald'

Rest API

# Create the books dictionary with exact entries
# Your code here

Need a hint?

Use curly braces {} to create a dictionary with the exact book titles as keys and authors as values.

2

Set the requested book

Create a variable called requested_book and set it to the string 'The Catcher in the Rye'

Rest API

books = {
    '1984': 'George Orwell',
    'To Kill a Mockingbird': 'Harper Lee',
    'The Great Gatsby': 'F. Scott Fitzgerald'
}
# Set the requested_book variable to 'The Catcher in the Rye'
# Your code here

Need a hint?

Assign the exact string 'The Catcher in the Rye' to the variable requested_book.

3

Check for the book and prepare error messages

Write an if statement to check if requested_book is in books. If it is, create a variable result with the message "Found: {requested_book} by {author}". If not, set result to the error message "Error: '{requested_book}' not found in the library."

Rest API

books = {
    '1984': 'George Orwell',
    'To Kill a Mockingbird': 'Harper Lee',
    'The Great Gatsby': 'F. Scott Fitzgerald'
}
requested_book = 'The Catcher in the Rye'
# Check if requested_book is in books and set result with a human-readable message
# Your code here

Need a hint?

Use an if statement to check membership and f-strings to create clear messages.

4

Print the result

Write a print statement to display the variable result

Rest API

books = {
    '1984': 'George Orwell',
    'To Kill a Mockingbird': 'Harper Lee',
    'The Great Gatsby': 'F. Scott Fitzgerald'
}
requested_book = 'The Catcher in the Rye'

if requested_book in books:
    author = books[requested_book]
    result = f"Found: {requested_book} by {author}"
else:
    result = f"Error: '{requested_book}' not found in the library."

# Print the result variable
# Your code here

Need a hint?

Use print(result) to show the message on the screen.