At-least-once delivery in Kafka - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to commit the offset after processing the message.

Kafka

consumer.commitSync([1]);

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

Anull

Btrue

Cfalse

Doffsets

Attempts:

3 left

💡 Hint

Common Mistakes

Passing true or false instead of offsets causes errors.

Not committing offsets can lead to message reprocessing.

The commitSync method requires the offsets to commit, so 'offsets' is the correct argument.

2fill in blank

medium

Complete the code to enable auto-commit for at-least-once delivery.

Kafka

"enable.auto.commit": [1],

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

A"false"

BTrue

CFalse

D"true"

Attempts:

3 left

💡 Hint

Common Mistakes

Using string 'true' instead of boolean true causes config issues.

Setting auto-commit to false disables automatic commits.

Setting 'enable.auto.commit' to true enables automatic offset commits for at-least-once delivery.

3fill in blank

hard

Fix the error in the code to process messages and commit offsets synchronously.

Kafka

while (true) {
    ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(100));
    for (ConsumerRecord<String, String> record : records) {
        process(record);
    }
    consumer.[1]();
}

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

AcommitOffset

BcommitAsync

CcommitSync

Dcommit

Attempts:

3 left

💡 Hint

Common Mistakes

Using commitAsync() can cause message duplication.

commit() and commitOffset() are not valid Kafka consumer methods.

commitSync() commits offsets synchronously, ensuring at-least-once delivery guarantees.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that stores offsets for partitions with offset greater than 5.

Kafka

Map<TopicPartition, OffsetAndMetadata> offsets = records.partitions().stream()
    .collect(Collectors.toMap(
        partition -> partition,
        partition -> new OffsetAndMetadata([1])
    ));

if (offsets.entrySet().stream().anyMatch(entry -> entry.getValue().offset() [2] 5)) {
    consumer.commitSync(offsets);
}

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Arecords.records(partition).get(records.records(partition).size() - 1).offset() + 1

Brecords.records(partition).get(0).offset()

C>

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using the first record's offset instead of the last.

Using '<' instead of '>' in the condition.

The offset stored is the last record's offset plus one, and the condition checks if offset is greater than 5.

5fill in blank

hard

Fill all three blanks to create a Python dictionary comprehension that stores offsets for words longer than 3 characters.

Kafka

offsets = {word[1]: [2] for word in words if len(word) [3] 3}

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

A.upper()

Blen(word)

C>

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<=' instead of '>' in the condition.

Using the word itself instead of its uppercase form as key.

The comprehension uses the uppercase word as key, length as value, and filters words longer than 3 characters.