Grafana dashboard: Multi-value variable inserts braces in the payload #151376

Grafana
,
1

Hello,
I have a simple Grafana dashboard and there is an issue regarding parsing of JSON values using JSONPath language when in variable “Multi-value” is selected.
Here is the issue:
I have a variable which Queries “JSON API” datasource with the following parameters:
Type: Query
Name: tracker_id
Method: POST
Path: /tracker/list
Body:
{“hash”:“${hash_variable}”}
Multi-value: Enabled
Include all: Disabled
Fields:

  1. JSONPath: $.list[*].id

The preview works perfectly well and I receive tracker IDs in the preview.
Here is how the /tracker/list API responds in general:

{
  "list": [
    {
      "id": 2829403,
      "label": "TruckN12894j32",
      "group_id": 0,
      "source": {
        "status_listing_id": 116518,
        "id": 723127,
        "device_id": "164382878878",
        "blocked": false,
        "creation_date": "2022-12-20",
        "tariff_id": 17129,
        "model": "navixymobile_xgps",
        "tariff_end_date": "2024-09-01",
        "phone": null
      },
      "tag_bindings": [
        {
          "tag_id": 396232,
          "ordinal": 1
        }
      ],
      "clone": false
    },
    {
      "id": 2903030,
      "label": "FMC130",
      "group_id": 0,
      "source": {
        "status_listing_id": null,
        "id": 10159737,
        "device_id": "111222333444556",
        "blocked": false,
        "creation_date": "2023-08-03",
        "tariff_id": 17132,
        "model": "telfmu130_telfmb130",
        "tariff_end_date": "2025-03-29",
        "phone": "079123122312"
      },
      "tag_bindings": [
        {
          "tag_id": 412763,
          "ordinal": 1
        },
        {
          "tag_id": 412764,
          "ordinal": 2
        }
      ],
      "clone": false
    }
  ],
  "success": true
}

And everything works perfectly well, until I enable the option “Multi-value:Enabled”.

Whenever the option is selected and at least two trackers are selected in the drop down menu of the dashboard, Grafana brakes the JSON validity by inserting the “{ }” braces into a JSON array.

I enter the variable in another request body for forming a dashboard cell,
the body of the other request looks like this:
{"hash":"${hash}", "trackers":[$tracker_id], "allow_not_exist": true, "list_blocked": true}
OR
{"hash":"${hash}", "trackers":[${tracker_id}], "allow_not_exist": true, "list_blocked": true}

The braces are always inserted into the “trackers” array on multiple choice of the variable in the dashboard.
Here is what Grafana payload looks like in this case:

{“hash”:“abcdabcdabcdabcd777”, “trackers”:[{2829403,2903030}], “allow_not_exist”: true, “list_blocked”: true}

As you can see, the braces “{ }” brake the JSON validity and I cannot proceed with further using the dashboard with Multi-value enabled option.
Could you please clarify how can I avoid this breaking of JSON validity?

If I use a JSONPath evalutaor with the exact same JSON, I receive correct results:

[Album] imgur.com

However, Grafana, for some reason inserts the bracers in the request payload which prevents the request from being correctly responded.

Environment (with versions):

  • Grafana version: Grafana v10.4.0 (03f502a94d)
  • Operating system: Dockered
  • Browser: Chrome Version 128.0.6613.85 (Official Build) (64-bit)
  • Datasource version(s) (prometheus, graphite, etc.): JSON API
  • Plugins: -
2

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