Header-based versioning in Rest API - Mini Project: Build & Apply

Header-based Versioning in a REST API

📖 Scenario: You are building a simple REST API for a book store. You want to support different versions of the API using HTTP headers. This way, clients can specify which version of the API they want to use by sending a custom header.

🎯 Goal: Create a REST API endpoint that returns book information. Implement header-based versioning so that when the client sends X-API-Version: 1, the API returns the book title only, and when the client sends X-API-Version: 2, the API returns the book title and author.

📋 What You'll Learn

Create a dictionary called book with keys title and author and values 'The Great Gatsby' and 'F. Scott Fitzgerald' respectively.

Create a variable called version_header that simulates reading the 'X-API-Version' header from a request.

Use an if-elif-else statement to check the value of version_header and create a dictionary called response with the correct data for version 1 or 2.

Print the response dictionary.

💡 Why This Matters

🌍 Real World

APIs often need to support multiple versions so that old clients keep working while new features are added. Header-based versioning is one way to do this cleanly.

💼 Career

Understanding how to handle API versioning is important for backend developers and anyone working with web services to ensure smooth upgrades and backward compatibility.

1

DATA SETUP: Create the book data

Create a dictionary called book with these exact entries: 'title': 'The Great Gatsby' and 'author': 'F. Scott Fitzgerald'.

Rest API

# Create the book dictionary with title and author
# Your code here

Need a hint?

Use curly braces {} to create a dictionary with the keys and values exactly as shown.

2

CONFIGURATION: Simulate reading the version header

Create a variable called version_header and set it to the string '1' to simulate the 'X-API-Version' header value.

Rest API

book = {'title': 'The Great Gatsby', 'author': 'F. Scott Fitzgerald'}
# Create version_header variable with value '1'
# Your code here

Need a hint?

Assign the string '1' to the variable version_header.

3

CORE LOGIC: Create response based on version header

Use an if-elif-else statement to check if version_header is '1' or '2'. Create a dictionary called response that contains only 'title' from book if version is '1', or both 'title' and 'author' if version is '2'. If the version is neither, set response to {'error': 'Unsupported API version'}.

Rest API

book = {'title': 'The Great Gatsby', 'author': 'F. Scott Fitzgerald'}
version_header = '1'
# Use if-elif-else to create response dictionary based on version_header
# Your code here

Need a hint?

Use if to check for version '1', elif for version '2', and else for unsupported versions.

4

OUTPUT: Print the response

Write a print statement to display the response dictionary.

Rest API

book = {'title': 'The Great Gatsby', 'author': 'F. Scott Fitzgerald'}
version_header = '1'

if version_header == '1':
    response = {'title': book['title']}
elif version_header == '2':
    response = {'title': book['title'], 'author': book['author']}
else:
    response = {'error': 'Unsupported API version'}

# Print the response dictionary
# Your code here

Need a hint?

Use print(response) to show the final output.