Problems with tags in JSON data from an HTTP request in an InfluxDB using Telegraf

Telegraf
1

Hi,

Help. I am trying to store the JSON data from an HTTP request in an InfluxDB using Telegraf.
I get all the numeric data, but I cant seem to get the string data, or set any tags ?

I am reading JSON from various IoT devices running an open source firmware called Tasmota.
The status is retrieve via HTTP like this: http://temp03.local/cm?cmnd=status%200

Here’s a sample of the JSON output:

{
    "Status": {
        "Module": 0,
        "DeviceName": "Temp03",
		"FriendlyName": [
            "Temp03"
        ],
        "ButtonTopic": "0",
        "Power": 0,
        "LedState": 1,
        "SensorRetain": 0,
        "PowerRetain": 0
    },
    "StatusNET": {
        "Hostname": "temp03-1234",
        "IPAddress": "10.1.0.75",
        "Gateway": "10.1.0.1"
        }
    }
}

Here is my telegraf config:

[[inputs.http]]
  urls = ["http://temp03.local/cm?cmnd=status%200"]
  data_format = "json"
  json_query = ""
  tag_keys = ["Hostname"]
  json_string_fields = ["DeviceName","FriendlyName"]
  name_override = "tasmota"

I was expecting this :

tasmota,hostname=temp03-1234

but I get this :

InfluxDB shell version: 1.8.3
> use tasmota
Using database tasmota
> show series
key
---
tasmota,host=grafana,url=http://temp03.local/cm?cmnd\=status%200

I know I can get rid of the host and url tags with:
tagexclude = [“url”, “host”]

But why isnt the hostname=temp03-1234 tag there ?
I have tried :
tag_keys = [“Hostname”]
tag_keys = [“hostname”]
tag_keys = [“Status.Hostname”]
tag_keys = [“Status_Hostname”]
but none of those options work. I cant seem to get any tags included.

Secondly, none of the string based fields are in the database. Specifically I added json_string_fields=[“DeviceName”,“FriendlyName”] but I only have numeric data in the database.
Again I’ve tried
json_string_fields = [“DeviceName”]
json_string_fields = [“Status.DeviceName”]
etc.

Any pointers please?

Versions:
$ influx --version
InfluxDB shell version: 1.8.3
$ telegraf --version
Telegraf 1.16.3 (git: HEAD c7f21728)

Thanks!

Regards,

Jon.

2

Hi Jon,

Firstly, your JSON has an extra }, but this is probably because you edited it by hand.

What you want is:

  tag_keys = ["StatusNET_Hostname"]
  json_string_fields = ["Status_DeviceName","Status_FriendlyName_0"]

I hope this helps,

Richard

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