Help with msg.payload in a function/subflow needed

General
5

Java is not JavaScript. Totally different. So if you are reading up on Java, you are wasting your time. :joy:

So ignoring the environment variables for a second, you are essentially saying...

msg["payload.Volts"] =  "123456";
return msg;

Which will correctly set a property in msg named payload.Volts - as you are getting.

If you want nested objects e.g. a Volts property inside an object named payload inside the msg object you will have to approach this differently.