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Kafka Stream Output

Overview

Compatible Spark/Pyspark

The kafka_stream_output node writes record to a kafka topic. The input dataset must have a column named value, and an optional column named key. These column will be used for the written record value (resp. key).

Example(s)

In the following example the received dataset has a column parsed_log that we want to write to Kafka. We let our Kafka writer to map parsed_log as our value column.

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{
    job: [
        {
            type: kafka_stream_input
            component: input
            settings: {
                topic: mytenant_apache_httpd_archiving
                brokers: [
                    {
                        host : localhost
                        port : 9092
                    }
                ]
                start_offset_strategy : latest
            }
            publish: [
                    {
                        stream: data
                    }
                ]
        }
        {
            type: sql
            component: sql
            settings: {
                statement: SELECT  CAST(value AS STRING) AS parsed_log FROM input_data
            }
            subscribe: [
                {
                    component: input
                    stream: data
                }
            ]
            publish: [
                { 
                    stream: data
                }
            ]
        }
        {
            type: kafka_stream_output
            component: output
            settings: {
                topic: new_topic_for_test
                column_value: tmp
                mode: Append
                checkpoint_location: /tmp/kafkatest
                brokers: [
                    {
                        host : localhost
                        port : 9092
                    }
                ]
            }
            subscribe: [
                {
                    stream: data
                    component: sql
                }
            ]
        }
    ]
}

Configuration(s)

  • brokers: List

    Description: [REQUIRED] a list of json objects with two fields: host: String and port: Integer. This list is used to start a connection with your kafka cluster.

  • column_value: String

    Description: [NOT_REQUIRED] select the column data you want to store in your kafka cluster. By default, will consider that the incoming dataframe has a value column...

  • topic: String

    Description: [REQUIRED] name of the topic on which you want to push data.

  • checkpoint_location: String

    Description: [REQUIRED] path where you want to store checkpoint data in case of failure recovery.