Partition assignment in Kafka - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to assign a message to a specific partition.

Kafka

producer.send('my_topic', value=message, partition=[1])

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

A0

B1

Cpartition

Dtopic

Attempts:

3 left

💡 Hint

Common Mistakes

Using the topic name instead of a partition number.

Using a variable name that is not defined.

The partition number must be an integer indicating which partition to send the message to. Here, 0 is a valid partition index.

2fill in blank

medium

Complete the code to get the partition count for a topic.

Kafka

partitions = [tp.partition for tp in client.partitions_for_topic('[1]')]

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

Apartition

Bmy_topic

Ctopic

Dmessage

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name instead of a string literal.

Passing the partition number instead of the topic name.

You must provide the topic name as a string to get its partitions.

3fill in blank

hard

Fix the error in the code to assign partitions in a round-robin fashion.

Kafka

partition = partitions[[1] % len(partitions)]

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

Atopic

Bpartition

Ci

Dmessage

Attempts:

3 left

💡 Hint

Common Mistakes

Using the partition variable instead of the index.

Using the topic name as an index.

The variable 'i' is used as the index to cycle through partitions using modulo.

4fill in blank

hard

Fill both blanks to create a dictionary mapping partitions to messages.

Kafka

partition_map = {partition: messages[1] for partition, messages in data[2]

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A[:]

B.keys()

C.items()

D.values()

Attempts:

3 left

💡 Hint

Common Mistakes

Using .keys() instead of .items() for iteration.

Not copying the list of messages.

The slice [:] copies the messages list, and .items() iterates over dictionary key-value pairs.

5fill in blank

hard

Fill both blanks to filter partitions with more than 5 messages.

Kafka

filtered = {p: m for p, m in partition_map.items() if len(m) [1] 5 and p [2] 0}

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

A:

B>

C!=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' instead of '==' or '!=' in conditions.

Using ':' incorrectly in dictionary comprehension.

Use ':' to separate key and value in dict comprehension, '>' to check message count, and '!=' to exclude partition 0.

Practice

1.

What is the main purpose of partition assignment in Kafka?

easy

A. To encrypt messages before sending

B. To split topic data among consumers to share the workload

C. To compress data for faster transmission

D. To create new topics automatically

Solution

1. Step 1: Understand partition assignment role

   Partition assignment divides topic partitions among consumers to distribute processing.

2. Step 2: Compare options

   Only To split topic data among consumers to share the workload describes splitting data among consumers; others describe unrelated tasks.

3. Final Answer:

   To split topic data among consumers to share the workload -> Option B

4. Quick Check:

   Partition assignment = workload sharing [OK]

Hint: Partition assignment shares topic data among consumers [OK]

Common Mistakes:

• Confusing partition assignment with encryption
• Thinking it compresses data
• Assuming it creates topics

2.

Which of the following is a valid Kafka partition assignment strategy?

easy

A. RoundRobin

B. HashMap

C. QuickSort

D. BinarySearch

Solution

1. Step 1: Recall Kafka partition assignment strategies

   Kafka supports strategies like Range, RoundRobin, and Sticky.

2. Step 2: Identify valid strategy

   RoundRobin is a known Kafka strategy; others are unrelated algorithms.

3. Final Answer:

   RoundRobin -> Option A

4. Quick Check:

   RoundRobin = valid strategy [OK]

Hint: Remember Kafka uses RoundRobin, Range, Sticky strategies [OK]

Common Mistakes:

• Confusing general algorithms with Kafka strategies
• Choosing unrelated computer science terms
• Ignoring Kafka-specific terms

3.

Given a topic with 4 partitions and 2 consumers using the Range strategy, how are partitions assigned?

Partitions: 0, 1, 2, 3
Consumers: C1, C2
Strategy: Range

medium

A. Partitions are assigned randomly

B. C1 gets partitions 0 and 2; C2 gets partitions 1 and 3

C. C1 gets all partitions; C2 gets none

D. C1 gets partitions 0 and 1; C2 gets partitions 2 and 3

Solution

1. Step 1: Understand Range strategy behavior

   Range assigns consecutive partitions to each consumer in order.

2. Step 2: Apply Range to 4 partitions and 2 consumers

   Partitions 0 and 1 go to C1; partitions 2 and 3 go to C2.

3. Final Answer:

   C1 gets partitions 0 and 1; C2 gets partitions 2 and 3 -> Option D

4. Quick Check:

   Range = consecutive partition blocks [OK]

Hint: Range assigns consecutive partitions to consumers [OK]

Common Mistakes:

• Mixing RoundRobin with Range strategy
• Assuming random assignment
• Giving all partitions to one consumer

4.

Identify the error in this partition assignment code snippet using the Sticky strategy:

assignor = StickyAssignor()
assignor.assign(partitions=[0,1,2], consumers=["C1"])

medium

A. Consumers list must be integers

B. Partitions list should be empty

C. StickyAssignor requires at least two consumers for assignment

D. StickyAssignor does not support partition assignment

Solution

1. Step 1: Understand StickyAssignor requirements

   Sticky strategy balances partitions among multiple consumers to minimize movement.

2. Step 2: Check given consumers list

   Only one consumer is provided, so StickyAssignor cannot balance partitions.

3. Final Answer:

   StickyAssignor requires at least two consumers for assignment -> Option C

4. Quick Check:

   Sticky needs multiple consumers [OK]

Hint: Sticky strategy needs multiple consumers to balance partitions [OK]

Common Mistakes:

• Assuming single consumer works with Sticky
• Confusing consumer data types
• Thinking Sticky doesn't assign partitions

5.

You have 5 consumers and a topic with 10 partitions. You want to maintain processing order per partition and balance load evenly. Which partition assignment strategy should you choose?

hard

A. Sticky, because it balances partitions while minimizing reassignment

B. RoundRobin, because it distributes partitions evenly across consumers

C. Range, because it assigns consecutive partitions to consumers

D. Random, because it assigns partitions unpredictably

Solution

1. Step 1: Analyze requirements

   Need to keep processing order per partition and balance load evenly.

2. Step 2: Compare strategies

   Range assigns consecutive partitions but may imbalance load; RoundRobin balances evenly but can cause frequent partition moves; Sticky balances load and minimizes partition reassignment, preserving order.

3. Step 3: Choose best fit

   Sticky strategy best meets both order and load balance requirements.

4. Final Answer:

   Sticky, because it balances partitions while minimizing reassignment -> Option A

5. Quick Check:

   Sticky = balanced load + order preservation [OK]

Hint: Sticky balances load and keeps partition order [OK]

Common Mistakes:

• Choosing Range despite load imbalance
• Picking RoundRobin ignoring partition order
• Selecting random assignment which is unpredictable