Unfortunately I am struggling with a flow and I have too little knowledge to solve this.
I retrieve data from The Things Network via MQTT, which is only one field with air pressure ("luchtdruk"). This value is written in an Influx Database, as a CSV-file on the Raspberry and that CSV-file is uploaded to a web server via FTP.
This all goes well in the end, but when the LoRa end node is switched on, the TTN join is first confirmed. This first payload contains all kinds of information, but of course not yet the air pressure. That value is only added to the second and subsequent transmission. This join confirmation will generate an error in the Edit Node:
No columns template specified for object -> CSV.
And in the Edit Influx Out Node:
Error: A 400 Bad Request error occurred: {"error": "unable to parse 'air pressure': missing fields"}
I would like to avoid this by ignoring the first payload (the join) or by giving that first payload a fictitious value for the air pressure fields so that field is not empty.
Can someone advise me how best to do this?
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