Hi there,

i already build some custom sensors (templates) to monitor our cisco telepresence endpoints. All doing well except that one:

The expression filter doesn't work for me. With jsonpath.com my JSONPath Syntax looks ok and gave me the correct value.

The sensor in PRTG gave me this error: "Could no evaluate channel value of TouchPanel Status: expected type string for parameter 0 but got []interface {}."

Regarding the documention https://www.paessler.com/manuals/prtg/rest_custom_sensor

You can filter matches with [?<expression>]. This expression matches 35985021 in the example above because the first device is the only one with a beta channel: $.devices[?@.firmware.channel=="beta"].networks.a.rx_bytes ---

my jsonpath (working at http://jsonpath.com/ and http://www.jsonquerytool.com/#/JSONPath)

$.Status.Peripherals.ConnectedDevice[?(@.Type.Value=="TouchPanel")].Status I also tried without the () Doesn't work either.

Any hints?

Greetings from Berlin, Sebastian

Here my json output of the telepresence device

{
  "Status":{
    "Peripherals":{
      "ConnectedDevice":[
        {
          "id":"1004",
          "HardwareInfo":{
            "Value":"102310-1"
          },
          "ID":{
            "Value":"xx:xx:xx:xx:xx:xx"
          },
          "Name":{
            "Value":"Cisco TelePresence Touch"
          },
          "SoftwareInfo":{
            "Value":"ce9.6.1.4516ae5aaa1"
          },
          "Status":{
            "Value":"Connected"
          },
          "Type":{
            "Value":"TouchPanel"
          },
          "UpgradeStatus":{
            "Value":"None"
          }
        },
        {
          "id":"1016",
          "HardwareInfo":{
            "Value":"iPhone10,4"
          },
          "ID":{
            "Value":"xxxxx"
          },
          "Name":{
            "Value":"iPhone8"
          },
          "SoftwareInfo":{
            "Value":"ios-2.0.3"
          },
          "Status":{
            "Value":"Connected"
          },
          "Type":{
            "Value":"Byod"
          },
          "UpgradeStatus":{
            "Value":"None"
          }
        }
      ]
    }
  }
}

my template

{
 "prtg": {
  "description" : {
   "device": "Cisco Telepresence Devices",
   "query": "/getxml?location=status/Peripherals/ConnectedDevice",
   "comment":"Shows peripheral devices that are currently connected to the endpoint. via Expression filtered if Type = TouchPanel show Status",
  },
  "text": $.Status.Peripherals.ConnectedDevice[?@.Type.Value=="TouchPanel"].Status,
  "result": [
   {
    "channel": "TouchPanel Status",
    "value": lookup($.Status.Peripherals.ConnectedDevice[?@.Type.Value=="TouchPanel"].Status, "ResponseTimedOut", "Connected", "Unpairing", "LostConnection")
   }
   ]
 }
}

Article Comments

Hi there,

I think I found a small mistake in your template. The result needs to be pointed directly to the status value. It should look like the following:

{
 "prtg": {
  "description" : {
   "device": "Cisco Telepresence Devices",
   "query": "/getxml?location=status/Peripherals/ConnectedDevice",
   "comment":"Shows peripheral devices that are currently connected to the endpoint. via Expression filtered if Type = TouchPanel show Status",
  },
  "text": $.Status.Peripherals.ConnectedDevice[?@.Type.Value=="TouchPanel"].Status.value,
  "result": [
   {
    "channel": "TouchPanel Status",
    "value": lookup($.Status.Peripherals.ConnectedDevice[?@.Type.Value=="TouchPanel"].Status.value, "ResponseTimedOut", "Connected", "Unpairing", "LostConnection")
   }
   ]
 }
}


Please let me know if this solves your issue.

Kind regards,
Birk Guttmann, Tech Support Team


Mar, 2019 - Permalink

Hi Birk,

no same error :-/

What about the filter expression? with or without the brackets ()?

[?@.Type.Value=="TouchPanel"]

[?(@.Type.Value=="TouchPanel")]

But both doesnt work.

This one: $.Status.Peripherals.ConnectedDevice[0].Status.Value works btw. so i think there is some error with filter expression module?

BR Sebastian


Mar, 2019 - Permalink

Hi there,

ok 1st learning:

Always use the rest.exe.

the above output is from the endpoint console (xpreferences outputmode json) but it seems to differ from the web output :-/ sorry for the confusion.

so this is the output from the rest.exe

{
  "Status": {
    "Peripherals": {
      "ConnectedDevice": [
        {
          "-item": 3191,
          "-maxOccurrence": "n",
          "HardwareInfo": "102310-1",
          "ID": "00:62:ec:8d:e8:36",
          "Name": "Cisco TelePresence Touch",
          "SoftwareInfo": "ce9.6.1.4516ae5aaa1",
          "Status": "Connected",
          "Type": "TouchPanel",
          "UpgradeStatus": "None"
        },
        {
          "-item": 3483,
          "-maxOccurrence": "n",
          "HardwareInfo": "proximity-desktop-osx",
          "ID": "e7e162b0",
          "Name": "marab",
          "SoftwareInfo": "desktop-3.0.0",
          "Status": "Connected",
          "Type": "Byod",
          "UpgradeStatus": "None"
        }
      ]
    },
    "apiVersion": 4,
    "product": "Cisco Codec",
    "version": "ce9.6.1.4516ae5aaa1"
  }
}

But still the same:

with $.Status.Peripherals.ConnectedDevice[?(@.Type == "TouchPanel")].Status

in JSONPath it is working in PRTG still the "Could no evaluate channel value of TouchPanel Status: expected type string for parameter 0 but got []interface {}."

?!?


Mar, 2019 - Permalink

I'll forward this to the developer so he can check it out :) Not sure what's missing here either :D

PRTGapi | Feature Requests | WMI Issues | SNMP Issues

Kind regards,
Stephan Linke, Tech Support Team


Mar, 2019 - Permalink

Could you try the following syntax instead: "value": $.Status.Peripherals.ConnectedDevice[?@.Type.Value=="TouchPanel"].Status.value.(lookup(@, "ResponseTimedOut", "Connected", "Unpairing", "LostConnection"))

It's basically the same as yours, but with the syntax appended instead of prepended, since you're retrieving possible multiple results. Let me know if it worked! :)

PRTGapi | Feature Requests | WMI Issues | SNMP Issues

Kind regards,
Stephan Linke, Tech Support Team


Mar, 2019 - Permalink

Hi Stephan,

now i got this:

Parsing error: { "prtg": { "description" : { "device": "Cisco Telepresence Devices", "query": "/getxml?location=status/Peripherals/ConnectedDevice", "comment":"Shows peripheral devices that are currently connected to the endpoint. via Expression filtered if Type = TouchPanel show Status", }, "text": $.Status.Peripherals.ConnectedDevice[?(@.Type == "TouchPanel")].Status, "result": [ { "channel": "TouchPanel Status", "value": $.Status.Peripherals.ConnectedDevice[?@.Type.Value=="TouchPanel"].Status.value.(lookup(@, "ResponseTimedOut", "Connected", "Unpairing", "LostConnection")) } ] } }:13:90 - 13:91 unexpected "(" while scanning JSON select expected Ident, "." or "*".

:-/


Apr, 2019 - Permalink

I've forwarded it to the corresponding developer - may take a bit until I hear from him, though.

PRTGapi | Feature Requests | WMI Issues | SNMP Issues

Kind regards,
Stephan Linke, Tech Support Team


Apr, 2019 - Permalink

I beg your pardon, this took way longer than anticipated. The actual correct template would be this one: 

{
 "prtg": {
  "description" : {
   "device": "Cisco Telepresence Devices",
   "query": "/getxml?location=status/Peripherals/ConnectedDevice",
   "comment":"Shows peripheral devices that are currently connected to the endpoint. via Expression filtered if Type = TouchPanel show Status",
  },
  "result": [
   {
    "channel": "TouchPanel Status",
    "value": lookup($($.Status.Peripherals.ConnectedDevice[?@.Type=="TouchPanel"].Status)[0], "ResponseTimedOut", "Connected", "Unpairing", "LostConnection")
   }
   ],
   "text": $.Status.Peripherals.ConnectedDevice[?@.Type=="TouchPanel"].Status,
 }
}

Just tested it with your sample output and it yields the following:



Now you just need to come up with a corresponding lookup :)

PRTGapi | Feature Requests | WMI Issues | SNMP Issues

Kind regards,
Stephan Linke, Tech Support Team


Apr, 2019 - Permalink

Hi Stephan,

yes no it is working. But unfortunately the output can be in the forms.

1. the working one, with an array the touchpanel and a desktop with the proximity client is connected

{
  "Status": {
    "Peripherals": {
      "ConnectedDevice": [
        {
          "-item": 1004,
          "-maxOccurrence": "n",
          "HardwareInfo": "102310-1",
          "ID": "00:00:00:00:00:00",
          "Name": "Cisco TelePresence Touch",
          "SerialNumber": "00000000000",
          "SoftwareInfo": "ce9.7.1.30bff6140aa",
          "Status": "Connected",
          "Type": "TouchPanel",
          "UpgradeStatus": "None"
        },
        {
          "-item": 1068,
          "-maxOccurrence": "n",
          "HardwareInfo": "proximity-desktop-osx",
          "ID": "a9f300fe",
          "Name": "username",
          "SerialNumber": "unknown",
          "SoftwareInfo": "desktop-3.0.3",
          "Status": "Connected",
          "Type": "Byod",
          "UpgradeStatus": "None"
        }
      ]
    },
    "apiVersion": 4,
    "product": "Cisco Codec",
    "version": "ce9.7.1.30bff6140aa"
  }
}

and the not working one

2. without an array because only one device (the touchpanel) is connected)

{
  "Status": {
    "Peripherals": {
      "ConnectedDevice": {
        "-item": 1004,
        "-maxOccurrence": "n",
        "HardwareInfo": "102310-1",
        "ID": "00:00:00:00:00:00",
        "Name": "Cisco TelePresence Touch",
        "SerialNumber": "0000000000",
        "SoftwareInfo": "ce9.7.1.30bff6140aa",
        "Status": "Connected",
        "Type": "TouchPanel",
        "UpgradeStatus": "None"
      }
    },
    "apiVersion": 4,
    "product": "Cisco Codec",
    "version": "ce9.7.1.30bff6140aa"
  }
}

Do you or the developer have an idea how to fix that?

Sebastian


May, 2019 - Permalink

Ah, so it's not a JSON array when there's only one connected? Something like this might work:

lookup($($.Status.Peripherals.ConnectedDevice[?@.Type=="TouchPanel"].Status), "ResponseTimedOut", "Connected", "Unpairing", "LostConnection")

Note the missing [0]. So for devices like that, only another Sensor would work I guess. Not sure if you can discern between the two in the first place - like, if they're hardwired and won't change without you getting notified?

PRTGapi | Feature Requests | WMI Issues | SNMP Issues

Kind regards,
Stephan Linke, Tech Support Team


May, 2019 - Permalink