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How to interpret JSON-value as counter



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I have a json-http-request which gives me some kind of counter-value

I call http://xxx.mydomain.local/customers/served

which gives me

        "data": {
            "customers_served": {
                "today": 34,
                "ever": 14800

I am using the "HTTP XML/REST Value Sensor" and evaluate the node: /data/customers_served/ever I will get an ever increasing line as graphics because every day we get more customers served. This kind of graphics is good to display a temperature of a room.

But I am interested to look onto a graphic where I can see wether we are having a busy day or a day with low frequence of customers served. I am interested to see the *difference* to the last value in the graphics of PRTG. Is this possible to define somewhere?

Thanks, Richard

json performancecounter traffic

Created on Aug 6, 2017 6:01:29 PM by  richard-lippmann (0) 1

1 Reply



Your Vote:



Hello richard-lippmann,
thank you for your KB-Post.

What you're looking for is a Delta(counter) sensor/channel. However, this is currently not possible with the HTTP XML Rest Value sensor. I would advise you to measure/poll the /data/customers_served/today instead, this may give you the graph that you're looking for.

Otherwise, soon-to-be released PRTG version 17.x.33 will include a new sensor (Rest Custom) which will allow you to poll the "ever" value as a counter/difference sensor. Please keep in mind that the sensor will works like every other delta sensor in PRTG, with overflows occurring at 2^32-1 (Microsoft SQL v2 BETA in Difference mode)

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Aug 7, 2017 6:05:34 AM by  Luciano Lingnau [Paessler Support]

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