Kafka Connect TimestampConverter SMT Usage Reference for Confluent Platform

The TimestampConverter SMT (org.apache.kafka.connect.transforms.TimestampConverter) converts record timestamps between various formats, including Unix epoch integers, formatted strings, and Connect’s native Date or Timestamp types.

Description

This SMT applies to an individual field or to the entire value.

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

Note

The TimestampConverter SMT operates on one field at a time.

For timestamp-based topic routing, see Kafka Connect TimestampRouter SMT Usage Reference for Confluent Platform and Kafka Connect MessageTimestampRouter SMT Usage Reference for Confluent Platform.

Properties

Name	Description	Type	Default	Valid values	Importance
`target.type`	The target format for the converted timestamp.	string		string, unix, Date, Time, Timestamp	high
`field`	The specific field name to convert. If left empty, the entire record value is treated as the timestamp.	string	“”		high
`format`	The `java.text.SimpleDateFormat` pattern used to parse or generate string timestamps. For more details, see SimpleDateFormat.	string	“”		medium
`unix.precision`	The desired Unix precision for the timestamp in seconds, milliseconds, microseconds, or nanoseconds. Converting values using microseconds or nanoseconds can cause precision loss.	string	`milliseconds`	seconds, milliseconds, microseconds, nanoseconds	low
`replace.null.with.default`	Specifies whether to replace null fields with their defined default values. When set to `true`, the default value is applied. Otherwise, the field remains null.	boolean	`true`	`true` or `false`	medium

Examples

Convert a Unix epoch to a date string

This configuration snippet shows how to use TimestampConverter to transform a Unix epoch (represented as an int64 value) into a formatted date string.

"transforms": "TimestampConverter",
"transforms.TimestampConverter.type": "org.apache.kafka.connect.transforms.TimestampConverter$Value",
"transforms.TimestampConverter.format": "yyyy-MM-dd",
"transforms.TimestampConverter.target.type": "string"

Before: 1696521093

After: "2023-10-05"

Set the converter precision to microseconds

This configuration snippet shows how to use TimestampConverter to define the converter precision to microseconds. Converting values using microseconds or nanoseconds can cause precision loss.

"transforms.TimestampConverter.type": "org.apache.kafka.connect.transforms.TimestampConverter$Value",
"transforms.TimestampConverter.field": "event_date_long",
"transforms.TimestampConverter.unix.precision": "microseconds",
"transforms.TimestampConverter.target.type": "Timestamp"

Before: 1696521093

After: 1696521093000000

Predicates

Configure transformations with predicates to ensure they process only records that satisfy a particular condition. You can also use predicates in a transformation chain with the Kafka Connect Filter (Kafka) SMT Usage Reference for Confluent Platform to conditionally filter specific records. For more information, see Predicates.