# Reactor Kafka

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> OpenTelemetry Java agent instrumentation

This instrumentation enables messaging spans for Reactor Kafka message consumers.

- **Name**: `reactor-kafka-1.0`
- **Scope**: `io.opentelemetry.reactor-kafka-1.0`
- **Target versions**: `io.projectreactor.kafka:reactor-kafka:[1.0.0,)`
- **Library**: https://projectreactor.io/docs/kafka/release/reference/

## Telemetry

- **Span attributes**: `kafka.record.queue_time_ms`, `messaging.client_id`, `messaging.destination.name`, `messaging.destination.partition.id`, `messaging.kafka.message.key`, `messaging.kafka.message.offset`, `messaging.message.body.size`, `messaging.operation`, `messaging.system`

## Configuration

| Option | Type | Default | Description |
| --- | --- | --- | --- |
| `otel.instrumentation.messaging.experimental.capture-headers` | list |  | A comma-separated list of header names to capture as span attributes. |
| `otel.instrumentation.kafka.experimental-span-attributes` | boolean | false | Enables the capture of the experimental consumer attribute `kafka.record.queue_time_ms`. |
| `otel.instrumentation.messaging.experimental.receive-telemetry.enabled` | boolean | false | Enables experimental receive telemetry, which will cause consumers to start a new trace, with only a span link connecting it to the producer trace. |

## Data

- **JSON**: [/data/javaagent/instrumentations/reactor-kafka-1.0/reactor-kafka-1.0-0556f226d439.json](/data/javaagent/instrumentations/reactor-kafka-1.0/reactor-kafka-1.0-0556f226d439.json)
- **Explore**: [/java-agent/instrumentation/reactor-kafka-1.0](/java-agent/instrumentation/reactor-kafka-1.0)