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JSON Parser Error



Hi Guys,

I hope someone can help my by my Stubid question :-)

So I woud use the REST Custom Sensor to get data from Freifunk Node the URL is https://map.ffrn.de/data/nodes.json

So I Create a Template with following entries:

{ "prtg": { "description" : { "device": "SLR-Offloader-003", "comment": "demo" }, "result": [ { "channel": "online", "value": nodes.000c2904305e.flags.online } ] } }

But when I create the Sensor I get

Parsing error: { "prtg": { "description" : { "device": "SLR-Offloader-003", "comment": "demo" }, "result": [ { "channel": "online", "value": nodes.000c2904305e.flags.online } ] } }:10:23 - 10:27 unexpected Float while scanning object end expected "," or "}".

Hase someone a Idea to fix it and whats wrong?

Thanks all

custom freifunk json rest sensor

Created on Dec 31, 2019 11:31:59 AM

3 Replies



This is not valid Json,

"value": nodes.000c2904305e.flags.online

Needs to be

"value": "nodes.000c2904305e.flags.online"

But... keep in mind that PRTG can only handle integer and/or decimal values.
So "nodes.000c2904305e.flags.online" will still be an invalid output for PRTG.

Sensors | Multi Channel Sensors | Tools | Notifications

Kind regards,

[[http://prtgtoolsfamily.com]] PRTG Tools Family

Created on Dec 31, 2019 12:22:19 PM



Hi Thanks for the Reply,

I make a mistake but it does not work so that is the "New" template. So this is all test. Later I would greb more Details out of the JSON file.

so that is the new one

        "channel": "online",
        "value": $.nodes.000c2904305e.flags.online

About the handler, the Output of this is true or false I think prtg kan handle it :-)

Created on Dec 31, 2019 3:28:03 PM



Hi ehein,

Please note that the "value" parameter needs to be a integer or float. Please make sure the <Float> setting matches the kind of value provided. Otherwise PRTG will show 0 values.

Created on Jan 1, 2020 9:02:20 AM by  Moritz Heller [Paessler Support]

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