HoistField

The following provides usage information for the Apache Kafka® SMT org.apache.kafka.connect.transforms.HoistField.

Description

If the data has a schema, wrap data using the specified field name in a Struct; if the data does not have a schema, wrap data using the specified field name in a Map.

Use the concrete transformation type designed for the record key (org.apache.kafka.connect.transforms.HoistField$Key) or value (org.apache.kafka.connect.transforms.HoistField$Value).

Example

The configuration snippet below shows how to use HoistField to wrap the field name in a Struct.

"transforms": "HoistField",
"transforms.HoistField.type": "org.apache.kafka.connect.transforms.HoistField$Value",
"transforms.HoistField.field": "line"

Messages sent:

Foo
Bar

Topic result:

{"line":"Foo"}
{"line":"Bar"}

Properties

Name	Description	Type	Default	Valid Values	Importance
field	Field name for the single field that will be created in the resulting Struct or Map.	string		non-empty list	medium

Predicates

Transformations can be configured with predicates so that the transformation is applied only to records which satisfy a condition. You can use predicates in a transformation chain and, when combined with the Filter (Apache Kafka), predicates can conditionally filter out specific records. For details and examples, see Predicates.