Message broker architecture in Kafka - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this Kafka consumer code snippet?

Consider a Kafka consumer configured to read from a topic with 3 partitions. The consumer group has 2 consumers. What will be the number of partitions assigned to each consumer?

Kafka

from kafka import KafkaConsumer

consumer = KafkaConsumer(
    'my_topic',
    group_id='my_group',
    bootstrap_servers=['localhost:9092']
)

consumer.poll(timeout_ms=1000)

partitions = consumer.assignment()
print(len(partitions))

A 1

B 3

C 2

D 0

💡 Hint

Partitions are distributed among consumers in a group as evenly as possible.

With 3 partitions and 2 consumers, partitions are split as 2 and 1. So one consumer gets 2 partitions, the other gets 1. The code prints the number of partitions assigned to the consumer, which is 2 in this case.

🧠 Conceptual

intermediate

What is the role of a Kafka broker in message broker architecture?

Choose the best description of what a Kafka broker does in the message broker architecture.

A It stores and manages messages in topics and handles client requests.

B It produces messages to topics on behalf of producers.

C It consumes messages from topics and processes them.

D It acts as a load balancer for network traffic.

💡 Hint

Think about where messages are stored and how clients interact with Kafka.

A Kafka broker is a server that stores messages in topics and partitions. It handles requests from producers to write messages and from consumers to read messages.

🔧 Debug

advanced

Why does this Kafka producer code raise a serialization error?

Examine the Kafka producer code below. It raises a serialization error when sending a message. What is the cause?

Kafka

from kafka import KafkaProducer

producer = KafkaProducer(bootstrap_servers='localhost:9092')

message = {'key': 'value'}
producer.send('my_topic', message)
producer.flush()

A The bootstrap_servers parameter is incorrectly formatted.

B The topic 'my_topic' does not exist on the broker.

C The producer is missing the group_id parameter.

D The message must be bytes, but a dict was sent without serialization.

💡 Hint

Kafka producers require messages in a specific format before sending.

The KafkaProducer expects message values as bytes. Sending a Python dict without converting it to bytes causes a serialization error.

📝 Syntax

advanced

Which Kafka consumer code snippet correctly commits offsets automatically?

Identify the code snippet that enables automatic offset commits in a Kafka consumer.

A consumer = KafkaConsumer('topic', group_id='group', bootstrap_servers='localhost:9092', enable_auto_commit=True)

B consumer = KafkaConsumer('topic', group_id='group', bootstrap_servers='localhost:9092', auto_commit=True)

C consumer = KafkaConsumer('topic', group_id='group', bootstrap_servers='localhost:9092', commit_auto=True)

D consumer = KafkaConsumer('topic', group_id='group', bootstrap_servers='localhost:9092', auto_commit_offsets=True)

💡 Hint

Check the exact parameter name for enabling auto commit in KafkaConsumer.

The correct parameter to enable automatic offset commits is enable_auto_commit. Other options are invalid and cause errors.

🚀 Application

expert

How many partitions will be in the topic after this Kafka topic creation command?

You run the following command to create a Kafka topic:

kafka-topics.sh --create --topic orders --partitions 5 --replication-factor 3 --bootstrap-server localhost:9092

How many partitions will the topic orders have?

A 3

B 5

C 8

D 15

💡 Hint

The --partitions flag sets the number of partitions.

The command explicitly sets the topic to have 5 partitions. The replication factor controls copies, not partitions.