examples/mqtt-customize/README.md

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# Customized IoTDB-MQTT-Broker Example

## Function
```
The example is to show how to customize your MQTT message format
```

## Usage

* Define your implementation which implements `PayloadFormatter.java`
* modify the file in `src/main/resources/META-INF/services/org.apache.iotdb.db.mqtt.PayloadFormatter`:
  clean the file and put your implementation class name into the file
* compile your implementation as a jar file

  
Then, in your mqtt-service: 
* Create ${IOTDB_HOME}/ext/mqtt/ folder, and put the jar into this folder. 
** Start an IoTDB MqttService (in the mqtt-service module).
* Set the value of program parameter `-mqtt_payload_formatter` as the value of getName() in your implementation 
* Launch the IoTDB server.
* Now IoTDB will use your implementation to parse the MQTT message.