Validation error details in Rest API - Mini Project: Build & Apply

Validation error details

📖 Scenario: You are building a simple REST API that accepts user data. You want to check if the data is valid and show clear error messages when it is not.

🎯 Goal: Create a Python dictionary with user data, set a validation rule, check the data against the rule, and print detailed error messages if the data is invalid.

📋 What You'll Learn

Create a dictionary called user_data with keys name and age and exact values 'Alice' and 17

Create a variable called min_age and set it to 18

Use an if statement to check if user_data['age'] is less than min_age and create an error message string called error_message

Print the error_message string

💡 Why This Matters

🌍 Real World

APIs often need to check if user input is correct and show clear error messages to help users fix mistakes.

💼 Career

Understanding validation and error messages is important for backend developers, API designers, and anyone working with user input.

1

Create user data dictionary

Create a dictionary called user_data with keys 'name' and 'age' and values 'Alice' and 17 exactly.

Rest API

# Create the user_data dictionary with name 'Alice' and age 17
# Your code here

Need a hint?

Use curly braces to create a dictionary. Keys are strings and values are 'Alice' and 17.

2

Set minimum age for validation

Create a variable called min_age and set it to the integer 18.

Rest API

user_data = {'name': 'Alice', 'age': 17}
# Create min_age variable and set it to 18
# Your code here

Need a hint?

Just assign 18 to the variable min_age.

3

Check age and create error message

Use an if statement to check if user_data['age'] is less than min_age. If true, create a string variable called error_message with the text 'User is too young: age is X' where X is the actual age from user_data.

Rest API

user_data = {'name': 'Alice', 'age': 17}
min_age = 18
# Check age and create error_message if age is less than min_age
# Your code here

Need a hint?

Use an if statement and an f-string to include the age in the message.

4

Print the error message

Print the variable error_message to show the validation error details.

Rest API

user_data = {'name': 'Alice', 'age': 17}
min_age = 18
if user_data['age'] < min_age:
    error_message = f"User is too young: age is {user_data['age']}"
# Print the error_message
# Your code here

Need a hint?

Use print(error_message) inside the if block.