Kafka Sink Node

Quick Reference

Name	Description
Kafka Broker	The address of your Kafka broker ex: localhost:9092
Topic	The name of the Kafka topic to consume from ex: my-topic
Partition Key Expression	A path selection expression to extract the Kafka message Key from the record. If blank, the key will be null. ex: $.user_id
Encoding Type	The format of the data in the Kafka topic
Additional Properties	Extra Kafka configuration options as key–value pairs ex: security.protocol=SASL_SSL

💡 Tip: More info about encoding types can be found here

💡 Tip: More info about path selection expression can be found here

Overview

The Kafka Sink Node allows you to write processed data records from your Fleak workflow directly into an Apache Kafka topic.

Configuration

Field Name	Description	Required?	Default
Kafka Broker	The host:port (bootstrap servers) of your Kafka cluster (e.g., kafka-prod:9092).	Yes	N/A
Topic	The name of the destination Kafka topic.	Yes	N/A
Partition Key Expression	A path expression (e.g., $.user_id) used to extract a value from the record to serve as the Kafka message Key. If left blank, messages will be keyed as null (utilizing standard Kafka partitioning logic). More info about path expression can be found here	No	null
Encoding Type	The format used to serialize the record value (e.g., JSON Object). More info about encoding type can be found here	Yes	N/A
Additional Properties	Key-value pairs for advanced Kafka Producer configuration (see below).	No	None

Advanced Configuration Properties

You can add custom properties to the Additional Properties section to override defaults or add security configurations (like SASL/SSL). Common overrides might include:

• sasl.mechanism
• security.protocol
• sasl.jaas.config

The node applies the following performance defaults automatically unless overridden in the Additional Properties section:

• Compression: lz4 (High performance compression)
• Acks: 1 (Leader acknowledgment only)
• Retries: 3
• Batch Size (Kafka): 65536 bytes
• Linger: 10 ms

Note: The default acks setting is 1. If you require stronger durability guarantees (e.g., waiting for all replicas), you should add a property acks with value all.

Related Nodes

• kafkaSource: Read data from Kafka topics