Confluent Cloud overview in Kafka - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this Kafka producer code snippet in Confluent Cloud?

Consider this Kafka producer code snippet that sends a message to a topic in Confluent Cloud. What will be printed after successful message delivery?

Kafka

from confluent_kafka import Producer

conf = {'bootstrap.servers': 'pkc-xyz.us-west1.gcp.confluent.cloud:9092',
        'security.protocol': 'SASL_SSL',
        'sasl.mechanisms': 'PLAIN',
        'sasl.username': 'API_KEY',
        'sasl.password': 'API_SECRET'}

producer = Producer(conf)

def delivery_report(err, msg):
    if err is not None:
        print(f'Message delivery failed: {err}')
    else:
        print(f'Message delivered to {msg.topic()} [{msg.partition()}]')

producer.produce('my_topic', value='value1', callback=delivery_report)
producer.flush()

A Message delivery failed: Broker not available

B Message delivered to my_topic [0]

C Message delivered to my_topic [1]

D No output printed

💡 Hint

Think about the default partition assignment when no partition is specified.

By default, if no partition is specified, Kafka assigns the message to partition 0. So the delivery report prints the topic and partition 0.

🧠 Conceptual

intermediate

Which feature of Confluent Cloud ensures data is encrypted during transit?

Confluent Cloud provides several security features. Which one specifically ensures that data sent between clients and the cloud is encrypted?

A SASL_SSL

B Schema Registry

C Kafka Connect

D Kafka Streams

💡 Hint

Look for the protocol that combines authentication and encryption.

SASL_SSL combines SASL authentication with SSL encryption, ensuring data is encrypted during transit.

🔧 Debug

advanced

Why does this Kafka consumer in Confluent Cloud fail to receive messages?

Review the following consumer code snippet. It connects to Confluent Cloud but does not receive any messages. What is the most likely cause?

Kafka

from confluent_kafka import Consumer

conf = {'bootstrap.servers': 'pkc-xyz.us-west1.gcp.confluent.cloud:9092',
        'security.protocol': 'SASL_SSL',
        'sasl.mechanisms': 'PLAIN',
        'sasl.username': 'API_KEY',
        'sasl.password': 'API_SECRET',
        'group.id': 'my_group',
        'auto.offset.reset': 'earliest'}

consumer = Consumer(conf)
consumer.subscribe(['my_topic'])

msg = consumer.poll(1.0)
if msg is None:
    print('No message received')
elif msg.error():
    print(f'Error: {msg.error()}')
else:
    print(f'Received message: {msg.value().decode("utf-8")}')

consumer.close()

A The consumer is not polling long enough to receive messages

B The consumer group ID is missing or incorrect

C The topic name is misspelled in subscribe()

D The API key or secret is invalid

💡 Hint

Notice that poll() is called only once with a 1.0 second timeout.

A single call to poll(1.0) may time out before receiving the message due to potential network latency or broker processing delays in Confluent Cloud. Consumers typically poll in a loop.

📝 Syntax

advanced

What error does this Confluent Cloud Kafka producer code raise?

Examine the following code snippet. What error will it raise when run?

Kafka

from confluent_kafka import Producer

conf = {'bootstrap.servers': 'pkc-xyz.us-west1.gcp.confluent.cloud:9092',
        'security.protocol': 'SASL_SSL',
        'sasl.mechanisms': 'PLAIN',
        'sasl.username': 'API_KEY',
        'sasl.password': 'API_SECRET'}

producer = Producer(conf)

# Missing required argument 'value'
producer.produce('my_topic', key='key1')
producer.flush()

A TypeError: produce() missing 1 required positional argument: 'value'

B ValueError: Topic name cannot be empty

C RuntimeError: Producer not initialized

D No error, message sent with empty value

💡 Hint

Check the required parameters for the produce() method.

The produce() method has 'value=None' as the default for the value parameter, so no error is raised and a message with null value is sent.

🚀 Application

expert

How many partitions will the topic have after this Confluent Cloud CLI command?

You run this command to create a topic in Confluent Cloud:

ccloud kafka topic create my_topic --partitions 5 --config retention.ms=604800000

How many partitions will my_topic have?

A 10

B 1

C 5

D 0

💡 Hint

The --partitions flag sets the number of partitions.

The command explicitly sets the topic to have 5 partitions.