The Xentara MQTT client v2.0
User Manual
JSON Format for Fixed Payloads

Fixed and empty payloads are defined using a simple JSON string. A payload configuration for a fixed payload has the following format:

"payload": "Hello everyone! My name is Xentara."

or:

"payload": ""

The provided string is used for the payload as-is. If the string is empty, then the message will have an empty payload.