Event choreography vs orchestration in Kafka - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to publish an event to a Kafka topic named 'orders'.

Kafka

producer.send(new ProducerRecord<>("[1]", orderId, orderData));

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

Aorders

Bpayments

Cshipments

Dinventory

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong topic name causes events to be sent to unrelated services.

Misspelling the topic name leads to runtime errors.

The event must be sent to the 'orders' topic to notify other services about new orders.

2fill in blank

medium

Complete the code to consume events from the 'payments' topic.

Kafka

consumer.subscribe(Collections.singletonList("[1]"));

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

Apayments

Borders

Cshipments

Dinventory

Attempts:

3 left

💡 Hint

Common Mistakes

Subscribing to the wrong topic means missing important events.

Using an empty or null topic list causes errors.

Subscribing to the 'payments' topic allows the service to react to payment events.

3fill in blank

hard

Fix the error in the code that tries to orchestrate order processing by sending a command event.

Kafka

producer.send(new ProducerRecord<>("[1]", orderId, command));

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

Aorder-updates

Border-events

Corder-choreography

Dorder-commands

Attempts:

3 left

💡 Hint

Common Mistakes

Sending commands to event topics mixes orchestration with choreography.

Using a generic topic name causes confusion in message handling.

Commands should be sent to a dedicated 'order-commands' topic for orchestration.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps service names to their event topics only if the service is part of choreography.

Kafka

service_topics = {service: [1] for service in services if service [2] choreography_services}

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Aservice + "-events"

Bservice == "payment"

Cin

Dservice != "inventory"

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of 'in' for membership tests.

Not concatenating the '-events' suffix correctly.

The comprehension builds topic names by adding '-events' to service names that are in the choreography list.

5fill in blank

hard

Fill all three blanks to filter events with status 'completed' and map their IDs to payloads in a dictionary comprehension.

Kafka

completed_events = {event[1]: event[2] for event in events if event[3] == "completed"}

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

A.id

B.payload

C.status

D.type

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong property names like '.type' instead of '.status'.

Mixing keys and values in the comprehension.

This comprehension creates a dictionary where keys are event IDs and values are payloads, filtering only events with status 'completed'.