Fallback pattern in Microservices - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a fallback method for a microservice call.

Microservices

def get_user_data(user_id):
    try:
        return call_remote_service(user_id)
    except Exception:
        return [1]()

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

Alog_error

Bcall_remote_service

Cfallback_response

Draise_error

Attempts:

3 left

💡 Hint

Common Mistakes

Using the original service call inside the except block

Raising an error instead of returning fallback

The fallback method fallback_response is called when the remote service fails.

2fill in blank

medium

Complete the code to implement a fallback pattern using a circuit breaker.

Microservices

if circuit_breaker.is_open():
    response = [1]()
else:
    response = call_remote_service()

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

Afallback_response

Bcall_remote_service

Craise_exception

Dretry_call

Attempts:

3 left

💡 Hint

Common Mistakes

Calling the remote service even when circuit is open

Raising exceptions instead of fallback

When the circuit breaker is open, the system uses the fallback response to avoid calling the failing service.

3fill in blank

hard

Fix the error in the fallback implementation to handle service failure gracefully.

Microservices

def fetch_data():
    try:
        data = call_service()
    except Exception:
        data = [1]
    return data

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

Alog_error()

Bcall_service()

Craise Exception

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Calling the service again causing infinite loop

Raising exceptions instead of fallback

Returning None in the except block is a safe fallback to indicate failure without crashing.

4fill in blank

hard

Fill both blanks to implement a fallback with a timeout and default response.

Microservices

try:
    response = call_service(timeout=[1])
except TimeoutError:
    response = [2]()

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

A5

B10

Cfallback_response

Dretry_call

Attempts:

3 left

💡 Hint

Common Mistakes

Using too large timeout

Retrying instead of fallback on timeout

The timeout is set to 5 seconds, and fallback_response is used if a timeout occurs.

5fill in blank

hard

Fill all three blanks to create a fallback pattern with logging and default data.

Microservices

def get_data():
    try:
        return call_service()
    except Exception as e:
        [1](f"Service failed: {e}")
        return [2]()

fallback_response = lambda: [3]

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

Alog_error

Bfallback_response

C{"data": "default"}

Draise_exception

Attempts:

3 left

💡 Hint

Common Mistakes

Not logging errors

Raising exceptions instead of fallback

Fallback not returning default data

Errors are logged with log_error, fallback method fallback_response is called, which returns default data.