Having trouble with public dashboard and Business Forms (Volkov Labs) plugin

Hey there,

I have created a dashboard which works while authenticated, but it doesnt while its on a public dashboard. This was meant to be a basic conference room display panel, because Microsoft wants $50/mo to have a display panel with information I can get from the Graph API for free. The end goal is to throw this on a single URL android tablet running as a kiosk.

It uses the Grafana date picker to define {“from”:“now”,“to”:“now/d”}, so that it gets current and future meetings for the day from the Infinity API addon. It also uses the “${__from:date}” variable in the API POST query to create a meeting from the current timestamp.

When I run it logged into Grafana, it works great, and you see the instant meeting on the left. When I try to run it as a public dashboard, I get this message:
“Update Datasource Error: T.range is undefined”

I did see in the documentation that I needed context.grafana.templateService to use Grafana variables, so I added “const templateService = context.grafana.templateService” to my initial code request, but that yielded no changes.

In the Business Forms error message, I can see that it gets the date correctly, because the error message also includes the query, and the date/time is correct. Heres the full error message with sensitive data redacted:

Update Datasource Error: T.range is undefined
Request: {
  "columns": [],
  "filters": [],
  "format": "table",
  "global_query_id": "",
  "refId": "",
  "root_selector": "",
  "source": "url",
  "type": "json",
  "url": "https://graph.microsoft.com/v1.0/users/hydrogenconferenceroom@contoso.com/calendar/events",
  "url_options": {
    "body_content_type": "application/json",
    "body_type": "raw",
    "data": "{\r\n  \"subject\": \"Instant Meeting\",\r\n  \"body\": {\r\n    \"contentType\": \"HTML\",\r\n    \"content\": \"This meeting was booked via the meeting button on the Room Panel\"\r\n  },\r\n  \"start\": {\r\n      \"dateTime\": \"2025-06-20T20:55:16.768Z\"    ,\r\n      \"timeZone\": \"Eastern Standard Time\"\r\n  },\r\n  \"location\":{\r\n      \"displayName\":\"Hydrogen Conference Room\"\r\n  },\r\n  \"allowNewTimeProposals\": false,\r\n}",
    "headers": [
      {
        "key": "Prefer",
        "value": "outlook.timezone=\"Eastern Standard Time\""
      },
      {
        "key": "Content-Type",
        "value": "application/json"
      }
    ],
    "method": "POST"
  }
}

What T.range could this error be talking about? @mikhailvolkov I believe you might be the best person to ask.

@Kraw Public dashboards has limited support for data sources and I don’t think it can be supported from the Grafana side.

Darn, I was hoping maybe you had come across the T.range error previously and could point me in the right direction.

Thank you anyway for taking a look.

@Kraw You are welcome to open an issue in the GitHub repository for team to take a closer look: