Why delivery guarantees affect correctness in Kafka - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the Kafka consumer to read messages with at-least-once delivery guarantee.

Kafka

props.put("enable.auto.commit", [1]);

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

Atrue

Bfalse

C"true"

D"false"

Attempts:

3 left

💡 Hint

Common Mistakes

Using string values instead of boolean

Setting auto commit to true for at-least-once

Setting enable.auto.commit to false ensures manual commit, enabling at-least-once delivery.

2fill in blank

medium

Complete the code to configure Kafka producer for exactly-once delivery semantics.

Kafka

props.put("enable.idempotence", [1]);

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

Atrue

Bfalse

C"true"

D"false"

Attempts:

3 left

💡 Hint

Common Mistakes

Using string instead of boolean

Disabling idempotence for exactly-once

Setting enable.idempotence to true enables exactly-once delivery by avoiding duplicate messages.

3fill in blank

hard

Fix the error in the code to ensure at-most-once delivery by committing offsets before processing.

Kafka

consumer.commitSync();
processRecord(record);
// This ensures [1] delivery.

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

Aat-least-once

Bno

Cexactly-once

Dat-most-once

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing at-most-once with at-least-once

Committing after processing instead of before

Committing offsets before processing means messages might be lost if processing fails, ensuring at-most-once delivery.

4fill in blank

hard

Fill both blanks to create a Kafka consumer that disables auto commit and sets max poll records to 10.

Kafka

props.put("enable.auto.commit", [1]);
props.put("max.poll.records", [2]);

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

Afalse

Btrue

C"10"

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Using boolean true for auto commit when disabling

Using 10 as integer instead of "10" string for max poll records

Disabling auto commit requires false. max.poll.records expects a string value like "10".

5fill in blank

hard

Fill all three blanks to create a Kafka producer with idempotence enabled, retries set to 5, and acks set to all.

Kafka

props.put("enable.idempotence", [1]);
props.put("retries", [2]);
props.put("acks", [3]);

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

Afalse

B5

Call

Dtrue

Attempts:

3 left

💡 Hint

Common Mistakes

Setting idempotence to false

Using string instead of integer for retries

Using "\"all\"" with extra quotes for acks

Idempotence must be true to avoid duplicates. Retries is an integer 5. Acks set to all waits for all replicas.