RPI HA monitor and issue with Rest template sensor

Hi,

i am running on a couple of RPI this docker container which is basically doing nothing else creating the below JSON endpoint

{"cpu_temperature":34.7,"cpu_current":7.87,"cpu_free":91.3,"cpu_average":{"totalIdle":2900011600,"totalTick":3333677700,"avgIdle":2900011600,"avgTotal":3333677700},"drive":{"totalGb":"7.0","usedGb":"2.6","freeGb":"4.1","usedPercentage":"37.1","freePercentage":"58.6"},"memory":{"totalMemMb":477.66,"usedMemMb":219.91,"freeMemMb":257.75,"freeMemPercentage":53.96},"network":{"docker0":{"interface":"docker0","inputBytes":0,"outputBytes":0},"eth0":{"interface":"eth0","inputBytes":109154810,"outputBytes":29028296},"lo":{"interface":"lo","inputBytes":13065452,"outputBytes":13065452}},"wifiStats":true}

I am using this code to create proper sensor on my HA instance

- platform: rest
  name: Coral RPI
  resource: http://mysecreIP:9999/
  timeout: 60
  json_attributes:
    - cpu_current
    - cpu_free
    - cpu_average
    - cpu_temperature
    - drive
    - memory
    - network
  value_template: '{{ value_json.value}}'
  headers:
    Content-Type: application/json
    User-Agent: Home Assistant Agent

and it work fine but i get the log spammed by

Template variable warning: 'dict object' has no attribute 'value' when rendering '{{ value_json.value}}'

I am very green on JSON so very likely I am doing something wrong here but can’t understand what.
Can someone help?

Your template is:

{{ value_json.value }}

your json is

{
  "cpu_temperature":34.7,
  "cpu_current":7.87,
  "cpu_free":91.3,
  "cpu_average":{
    "totalIdle":2900011600,
    "totalTick":3333677700,
    "avgIdle":2900011600,
    "avgTotal":3333677700
  },
  "drive":{
    "totalGb":"7.0",
    "usedGb":"2.6",
    "freeGb":"4.1",
    "usedPercentage":"37.1",
    "freePercentage":"58.6"
  },
  "memory":{
    "totalMemMb":477.66,
    "usedMemMb":219.91,
    "freeMemMb":257.75,
    "freeMemPercentage":53.96
  },
  "network":{
    "docker0":{
      "interface":"docker0",
      "inputBytes":0,
      "outputBytes":0
    },
    "eth0":{
      "interface":"eth0",
      "inputBytes":109154810,
      "outputBytes":29028296
    },
    "lo":{
      "interface":"lo",
      "inputBytes":13065452,
      "outputBytes":13065452
    }
  },
  "wifiStats":true
}

value_json equals your json above. So answer the following question:

Does "value" exist in your json?