Topic creation in Kafka - Step-by-Step Execution

Process Flow - Topic creation

Start

↓

Define Topic Name

↓

Set Configurations

↓

Send Create Topic Request

↓

Kafka Server Validates

↓

If Valid

→Topic Created

↓

If Invalid

→Error Returned

↓

End

This flow shows how a topic is created by defining its name and settings, sending a request to Kafka, which then validates and either creates the topic or returns an error.

Execution Sample

Kafka

from kafka.admin import KafkaAdminClient, NewTopic

admin_client = KafkaAdminClient(bootstrap_servers='localhost:9092')
new_topic = NewTopic(name='my_topic', num_partitions=3, replication_factor=1)
admin_client.create_topics(new_topics=[new_topic])

This code creates a Kafka topic named 'my_topic' with 3 partitions and a replication factor of 1.

Process Table

Step	Action	Input/Condition	Result
1	Initialize KafkaAdminClient	bootstrap_servers='localhost:9092'	Client ready to send requests
2	Define NewTopic	name='my_topic', num_partitions=3, replication_factor=1	Topic object created
3	Call create_topics	new_topics=[new_topic]	Request sent to Kafka server
4	Kafka server validates	Topic name valid, partitions and replication valid	Topic created successfully
5	Return from create_topics	No errors	Topic creation confirmed

💡 Topic created successfully after validation by Kafka server

Status Tracker

Variable	Start	After Step 2	After Step 3	Final
admin_client	None	KafkaAdminClient instance	KafkaAdminClient instance	KafkaAdminClient instance
new_topic	None	NewTopic(name='my_topic', num_partitions=3, replication_factor=1)	NewTopic object passed to create_topics	NewTopic object created on server

Key Moments - 2 Insights

Why do we need to specify the number of partitions and replication factor when creating a topic?

Partitions determine how data is split and parallelized; replication factor controls fault tolerance. This is shown in execution_table step 2 where these values are set before creation.

What happens if the topic name is invalid or already exists?

Kafka server validates the request (step 4). If invalid or duplicate, an error is returned instead of creating the topic.

Visual Quiz - 3 Questions

Look at the execution_table, what is the result after step 3?

A Request sent to Kafka server

B Topic created successfully

C Error returned

D Client initialization

💡 Hint

Check the 'Result' column for step 3 in execution_table

At which step does Kafka validate the topic creation request?

A Step 2

B Step 3

C Step 4

D Step 5

💡 Hint

Look at the 'Action' column in execution_table for validation

If you change the replication factor to 2, which variable in variable_tracker changes?

A admin_client

B new_topic

C bootstrap_servers

D None

💡 Hint

Replication factor is part of the NewTopic object tracked in variable_tracker

Concept Snapshot

Kafka Topic Creation:
- Use KafkaAdminClient to connect
- Define NewTopic with name, partitions, replication
- Call create_topics with the NewTopic list
- Kafka validates and creates topic
- Errors if invalid or duplicate

Full Transcript

This visual trace shows how to create a Kafka topic programmatically. First, a KafkaAdminClient is initialized to connect to the Kafka server. Then, a NewTopic object is defined with the topic name, number of partitions, and replication factor. The create_topics method is called with this topic list, sending a request to the Kafka server. The server validates the topic name and settings. If valid, the topic is created successfully; otherwise, an error is returned. Variables like admin_client and new_topic track the client and topic state through the process.