What this template does
Bridges the Coreflux MQTT broker and an Apache Kafka cluster in both directions from a single route. Telemetry published on plant/sensors/+/reading is produced to the Kafka topic plant.sensors.raw keyed by device id, so every reading from one machine stays on one partition and keeps its order, while records arriving on plant.commands are consumed back onto MQTT plant/commands/in for the field. Credentials never appear in the LoT: the bootstrap address and consumer group are read from runtime ENV values and the SASL password from the secret store, with a PLAINTEXT profile for local clusters and a SASL_SSL profile for Confluent Cloud, Amazon MSK and Aiven. A two machine simulator publishes readings on a five second timer, so the whole path can be exercised with no hardware and no real Kafka producer.
When to use it
Use it when MQTT edge telemetry has to reach a Kafka based analytics or data pipeline while commands, setpoints and alarms travel back to the field, and when the project needs the durable, replayable stream Kafka gives rather than the fire and forget delivery of MQTT alone.