HELP extract data from object/json

General
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1

Sorry but I have need to parse this object

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I want extra VolV for each element of array

{"topic":"energy_measurs","payload":{"serial":"A07766","measurs":[{"phaseId":0,"voltV":223,"currentA":2.038,"powerW":364,"powerFactor":0.8009999990463257},{"phaseId":1,"voltV":225.3000030517578,"currentA":2.102,"powerW":412,"powerFactor":0.8690000176429749},{"phaseId":2,"voltV":231.1999969482422,"currentA":0.624,"powerW":80,"powerFactor":0.5569999814033508}],"totPowerW":856,"errorSensor":0}}

2

Do you really want to create a custom node to do this? If not, could we please ask you to change the category to "general".

1 Like
3

"An extra VolV" I assume you mean an extra VoltV.
A Change Node with a jsonata expression will do the job.

$$ ~> |payload.measurs|{"VoltV2": voltV}|
You can play with it here. As the test on the JSONata expression editor does not allow

[{"id":"1c99cc328f943a7f","type":"function","z":"66277e057a573726","name":"function 12","func":"msg = {\"topic\":\"energy_measurs\",\"payload\":{\"serial\":\"A07766\",\"measurs\":[{\"phaseId\":0,\"voltV\":223,\"currentA\":2.038,\"powerW\":364,\"powerFactor\":0.8009999990463257},{\"phaseId\":1,\"voltV\":225.3000030517578,\"currentA\":2.102,\"powerW\":412,\"powerFactor\":0.8690000176429749},{\"phaseId\":2,\"voltV\":231.1999969482422,\"currentA\":0.624,\"powerW\":80,\"powerFactor\":0.5569999814033508}],\"totPowerW\":856,\"errorSensor\":0}}\nreturn msg;","outputs":1,"timeout":0,"noerr":0,"initialize":"","finalize":"","libs":[],"x":370,"y":760,"wires":[["b970d4c17e6a7fc7"]]},{"id":"f3804042146bfa36","type":"inject","z":"66277e057a573726","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":160,"y":760,"wires":[["1c99cc328f943a7f"]]},{"id":"223c3c71312ca5da","type":"debug","z":"66277e057a573726","name":"debug 92","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":760,"y":760,"wires":[]},{"id":"b970d4c17e6a7fc7","type":"change","z":"66277e057a573726","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"$$ ~> |payload.measurs|{\"VoltV2\": voltV}|","tot":"jsonata"}],"action":"","property":"","from":"","to":"","reg":false,"x":580,"y":760,"wires":[["223c3c71312ca5da"]]}]
4

Sorry for my English.

I need to extract the tree value of Volts to create 3 sensor from array of json message

5

Change Node > Set msg.voltV0 = payload.measurs[0].voltV

Same for the rest
payload.measurs[1].voltV
payload.measurs[2].voltV

The "Copy path" button in the debug window is your friend

6

Thanks perfect!!!!