Cache-aside pattern in Azure - Mini Project: Build & Apply

Implementing Cache-Aside Pattern with Azure Cache for Redis

📖 Scenario: You are building a web application that fetches user profile data from a database. To improve performance and reduce database load, you want to implement the cache-aside pattern using Azure Cache for Redis.

🎯 Goal: Build a simple cache-aside mechanism where the application first checks Azure Cache for Redis for user profile data. If the data is not found (cache miss), it fetches from the database and then stores it in the cache for future requests.

📋 What You'll Learn

Create a dictionary called database with user IDs as keys and profile names as values.

Create a variable called cache as an empty dictionary to simulate Azure Cache for Redis.

Write a function called get_user_profile that takes a user_id parameter.

Inside get_user_profile, check if user_id exists in cache and return the cached value if found.

If not found in cache, fetch the profile from database, store it in cache, and then return it.

💡 Why This Matters

🌍 Real World

Cache-aside pattern is widely used in cloud applications to reduce database load and improve response times by caching frequently accessed data.

💼 Career

Understanding and implementing caching strategies like cache-aside is essential for cloud engineers and developers working with scalable, high-performance applications.

1

Create the initial database dictionary

Create a dictionary called database with these exact entries: "user1": "Alice", "user2": "Bob", "user3": "Charlie".

Azure

# Create the database dictionary with user profiles
# Your code here

Need a hint?

Use curly braces to create a dictionary with the exact keys and values.

2

Create the cache dictionary

Create an empty dictionary called cache to simulate Azure Cache for Redis.

Azure

database = {"user1": "Alice", "user2": "Bob", "user3": "Charlie"}
# Create an empty cache dictionary
# Your code here

Need a hint?

Use empty curly braces to create an empty dictionary.

3

Write the cache-aside function

Write a function called get_user_profile that takes a parameter user_id. Inside the function, check if user_id exists in cache. If yes, return the cached value. Otherwise, fetch the profile from database, store it in cache, and then return it.

Azure

database = {"user1": "Alice", "user2": "Bob", "user3": "Charlie"}
cache = {}
# Define the get_user_profile function
# Your code here

Need a hint?

Use if user_id in cache to check cache. Use database.get(user_id) to fetch from database.

4

Complete by adding a sample call

Add a line that calls get_user_profile with "user2" and assigns the result to a variable called result.

Azure

database = {"user1": "Alice", "user2": "Bob", "user3": "Charlie"}
cache = {}

def get_user_profile(user_id):
    if user_id in cache:
        return cache[user_id]
    profile = database.get(user_id)
    if profile is not None:
        cache[user_id] = profile
    return profile

# Call get_user_profile with "user2" and store in result
# Your code here

Need a hint?

Call the function with the exact string "user2" and assign it to result.