Messages in Kafka the Types and Details

A message, also called a record, is the basic piece of data flowing through Kafka. Messages are how Kafka represents your data.

Kafka producer Vs. consumer messages

Kafka is an intermediate server that receives a message from a producer and sends them to the consumer. Here is a set of 10 Kafka Interview Questions.

Kafka message format

Each message has a timestamp, a value, and an optional key. Custom headers can be used if desired as well. 

A simple example of a message could be something like the following: the machine with host ID “1234567” (a message key) failed with the message “Alert: Machine Failed” (a message value) at “2020-10-02T10:34:11.654Z” (a message timestamp). Here is Kafka's flowchart for dummies.

Kafka record

The above image shows probably the most important and common parts of a message that users deal with directly.

Each key and value can interact in its own specific ways to serialize or deserialize its data.

Now that we have a record, how do we let Kafka know about it? You will deliver this message to Kafka by sending it to what is known as brokers.

References

• Kafka in action
• Apache Kafka for beginners