Working with weather station data JSON

General
1

What is the best way to pull say the temperature out of this JSON object and drop it into msg.payload. So far the examples I have found are more down the line of multiple devices all sending temperature and separating out the separate devices.

{"observations":[{"stationID":"ISTORE","obsTimeUtc":"2023-02-09T04:20:01Z","obsTimeLocal":"2023-02-08 22:20:01","neighborhood":"Ste. Anne","softwareType":"AMBWeatherV4.2.6","country":"CA","solarRadiation":0.2,"lon":-76.08,"realtimeFrequency":null,"epoch":16401,"lat":47.633,"uv":0,"winddir":10,"humidity":96,"qcStatus":-1,"imperial":{"temp":30,"heatIndex":30,"dewpt":30,"windChill":26,"windSpeed":5,"windGust":6,"pressure":29.02,"precipRate":0,"precipTotal":0.03,"elev":247}}]}
2

The documentation describes how to work with messages.

3

Feed the data into a debug node, then you can explore it's structure.
There is a "Copy path" button which in this example gives "payload.observations[0].imperial.temp"

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4

I hadn't realized this earlier.

I built a function node with

var temp = msg.payload.observations[0].imperial.temp

msg.payload = temp;
return msg;

in hopes that it would change the new payload to the temperature. In stead it give an error

TypeError: Cannot read properties of undefined (reading '0')

EDIT: This does work my wire was to the wrong place.

5

Ok I got it, it works as expected. I looked closer and the wire was direct from the inject node and not going through the http request node.