Eventual consistency handling in Microservices - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to identify the consistency model used in microservices.

Microservices

if system.consistency == '[1]':
    print("Updates will be visible eventually.")

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

Astrong consistency

Bimmediate consistency

Ceventual consistency

Dstrict consistency

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing strong consistency which requires immediate update visibility.

Eventual consistency means updates will be visible after some time, not immediately.

2fill in blank

medium

Complete the code to implement a retry mechanism for eventual consistency.

Microservices

def update_service(data):
    try:
        send_update(data)
    except [1]:
        retry_later(data)

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

AKeyError

BValueError

CSyntaxError

DTimeoutError

Attempts:

3 left

💡 Hint

Common Mistakes

Using ValueError which is unrelated to network issues.

TimeoutError is common when a service is temporarily unavailable, so retrying later helps eventual consistency.

3fill in blank

hard

Fix the error in the code that handles event ordering for eventual consistency.

Microservices

def process_event(event):
    if event.timestamp [1] last_processed_timestamp:
        apply_event(event)
        last_processed_timestamp = event.timestamp

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

A>=

B>

C<

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' which processes older events incorrectly.

Using '>' ensures only newer events are processed, preserving order for eventual consistency.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that filters events newer than a timestamp.

Microservices

filtered_events = {e.id: e for e in events if e.timestamp [1] cutoff_timestamp and e.status [2] 'pending'}

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

A>

B==

C!=

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' for timestamp which selects older events.

We want events with timestamp greater than cutoff and status exactly 'pending'.

5fill in blank

hard

Fill all three blanks to build a dictionary comprehension that maps event keys to values for confirmed events after a timestamp.

Microservices

confirmed_events = {event.[1]: event.[2] for event in event_list if event.[3] > last_sync_time}

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

Akey

Bvalue

Ctimestamp

Dstatus

Attempts:

3 left

💡 Hint

Common Mistakes

Using status instead of timestamp for filtering.

We map event keys to values for events with timestamp greater than last sync time.