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Kafka Connect Transformations¶
Single Message Transformations (SMTs) are applied to messages as they flow through Connect. SMTs transform inbound messages after a source connector has produced them, but before they are written to Kafka. SMTs transform outbound messages before they are sent to a sink connector.
These single message transforms (SMTs) are available for use with Kafka Connect:
|Cast fields or the entire key or value to a specific type, e.g. to force an integer field to a smaller width.
|Drop either a key or a value from a record and set it to null.
|Extract the specified field from a Struct when schema present, or a Map in the case of schemaless data. Any null values are passed through unmodified.
|Replace the record topic with a new topic derived from its key or value.
|Flatten a nested data structure. This generates names for each field by concatenating the field names at each level with a configurable delimiter character.
|Wrap data using the specified field name in a Struct when schema present, or a Map in the case of schemaless data.
|Insert field using attributes from the record metadata or a configured static value.
|Mask specified fields with a valid null value for the field type.
|Update the record topic using the configured regular expression and replacement string.
|Filter or rename fields.
|Set the schema name, version, or both on the record’s key or value schema.
|Convert timestamps between different formats such as Unix epoch, strings, and Connect Date and Timestamp types.
|Update the record’s topic field as a function of the original topic value and the record timestamp.
|Replace the record key with a new key formed from a subset of fields in the record value.