Kafka-specific options (internal use).
optional
brokers: readonly string[]
Kafka bootstrap brokers.
optional
client: IKafkaFactory
Injected Kafka factory.
optional
clientId: string
Kafka client ID (default: 'messaging-client').
optional
defaultQueue: string
Default consumer group name.
optional
replyTopic: string
Topic every request-reply response is published to and read back from.
Kafka topics are durable cluster resources and this broker creates none, so
the topic must already exist (or auto.create.topics.enable must be on).
Each broker instance reads it under its own consumer group, so every
instance sees every reply and discards those it did not originate — give a
high-traffic service its own reply topic to bound that fan-out.
optional
logger: { error: (msg: string) => void; }
Optional logger for error reporting.