Attribute Links with value modification

Manager UI
1

Hello,

I’m using Attribute Links configuration option to populate asset attributes from another JSON attribute linked with MQTTLink Agent and it works fine. My Attribute Links JSON:

[
  {
    "ref": {
      "id": "5mEPbDgAIcTae1eI14DqGP",
      "name": "temperatura_akt"
    },
    "filters": [
      {
        "type": "jsonPath",
        "path": "$.object.TempC_SHT31",
        "returnFirst": true,
        "returnLast": false
      }
    ]
  }
]

Currently I want to populate this attribute (“temperatura_akt”) with value returned from MQTTLink but additionaly I want to sum it with a another attribute value (“delta_callib_temp”). “delta_callib_temp” attribute is defined within the same asset as “temperatura_akt”.
So finally (in pseudocode)

asset.temperatura_akt.value=$.object.TempC_SHT31+asset.delta_callib_temp.value

Is it possible?

I’ve tried to use Flow Rule, rule works but since “temperatura_akt” is “date point” attribute it creates new value for it instead of just update and on “History” chart for “temperatura_akt” we have 2 values for one MQTTLink action (value passed from AgentLink and few secs later new value generated by rule). So I think we need to somehow modify value in “Attribute Links” option

2

Hi!

Currently there is no support for summing values using Attribute links.
From my experience, your only option is to use Flow rules here.

Funny enough, I had a chat with @panos about this recently,
where he shared his ideas on this. :joy:

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