The JSON message decoder is used in real-time ingestion to decode JSON-formatted messages from Kafka topic and convert them into Pinot rows.

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Class

org.apache.pinot.plugin.inputformat.json.JSONMessageDecoder

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Configuration Example

Define it in your streamConfig within the table config: 
"streamConfig": {
  "streamType": "kafka",
  "stream.kafka.topic.name": "events_topic",
  "stream.kafka.consumer.type": "lowlevel",
  "stream.kafka.decoder.class.name": "org.apache.pinot.plugin.inputformat.json.JSONMessageDecoder",
  "stream.kafka.broker.list": "broker:9092"
}

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Decoder Behavior

  • Parses JSON strings using a fast JSON library (e.g., Jackson/Gson).
  • Converts each key-value pair into Pinot column values.
  • Logs and skips invalid or malformed messages.