Kafka Connect Filter (Confluent) SMT for Confluent Platform

The following provides usage information for the Confluent SMT io.confluent.connect.transforms.Filter. Include or drop records that match the filter.condition Predicate.

Description

Include or drop records that match the filter.condition predicate.

The filter.condition is a predicate specifying JSON Path that is applied to each record processed, and when this predicate successfully matches the record is either included (when filter.type=include) or excluded (when filter.type=exclude).

The missing.or.null.behavior property defines how the transform behaves when a record does not have the field(s) used in the filter condition predicate. By default the behavior is to fail. This property can also be set to include or exclude the record that is missing the predicate’s field(s).

Use the transformation type designed for the record key (io.confluent.connect.transforms.Filter$Key) or value (io.confluent.connect.transforms.Filter$Value).

Installation

This transformation is developed by Confluent and does not ship by default with Kafka or Confluent Platform. You can install this transformation using the confluent connect plugin install command:

confluent connect plugin install confluentinc/connect-transforms:latest

Examples

The configuration snippet below shows how to use and configure the Confluent Filter SMT.

The filter.condition is a predicate specifying JSON path. For more information on JSON path format, see https://github.com/json-path/JsonPath.

filter.condition specified in the following examples is satisfied when the nested field 'nestedKey' in field 'key' is equal to either 'value1' or 'value2'.

Defines the configuration for including records satisfying the filter condition. The filter condition is applied on record value. The fail behavior in the configuration specifies to throw an exception and fail the connector task when the record does not have the field(s) used in the filter condition.

"transforms": "filterExample1",
"transforms.filterExample1.type": "io.confluent.connect.transforms.Filter$Value",
"transforms.filterExample1.filter.condition": "$.key[?(@.nestedKey == "value1" || @.nestedKey == "value2")]",
"transforms.filterExample1.filter.type": "include", "transforms.filterExample1.missing.or.null.behavior": "fail"

For additional examples, see Filter (Confluent) for fully-managed connectors.

Properties

Name Description Type Default Valid Values Importance
filter.condition Specifies the criteria used to match records to be included or excluded by this transformation. Use JSON Path predicate notation defined in: https://github.com/json-path/JsonPath. string     high
filter.type Specifies the action to perform with records that match the filter.condition predicate. Use include to pass through all records that match the predicate and drop all records that do not satisfy the predicate, or use exclude to drop all records that match the predicate. string   [include, exclude] high
missing.or.null.behavior Specifies the behavior when the record does not have the field(s) used in the filter.condition. Use fail to throw an exception and fail the connector task, include to pass the record through, or exclude to drop the record. string fail [fail, include, exclude] medium