Fix empty scope.nodes causing 400 Bad Request

[ktsaou]

Summary

• When no nodes are selected in the Grafana query editor, the plugin was sending scope.nodes: [] (empty array) to the Netdata Cloud API
• The API rejects empty arrays with 400 Bad Request
• This fix uses wildcard ['*'] when no nodes are selected, matching the UI tooltip behavior ("No selected Nodes means 'All Nodes' from the Room")

Root Cause

In src/shared/hooks/useGetChartData.ts, the nodes parameter defaulted to an empty array and was passed directly to scope.nodes without handling the "no selection = all nodes" case.

Changes

• useGetChartData.ts: Changed nodes, to nodes: nodes.length ? nodes : ['*'],

This is consistent with how selectors.nodes already uses ['*'] (line 69) and how dimensions and labels use defaultSelectorValue when empty.

Testing

• Lint passes (0 errors)
• Build passes
• Manual testing in Grafana with Netdata datasource

Fixes netdata/netdata-cloud#1132

[ktsaou]

@novykh check this

[novykh]

@ktsaou this wont fix it, since scope nodes are being sent to the cloud backend, where we use empty array for all nodes. If the backend was the agent then it would work. Please share what is braking so I can check it.

[novykh]

We can close this in favour of this. @ktsaou please approve.