Live: expose HTTP push endpoint that will read influx line protocol and publish to websocket (#32311)

Co-authored-by: Ryan McKinley <ryantxu@gmail.com>

packages/grafana-ui/src/components/GraphNG/utils.ts

@@ -90,6 +90,10 @@ export function preparePlotConfigBuilder(
 
   // X is the first field in the aligned frame
   const xField = frame.fields[0];
+  if (!xField) {
+    return builder; // empty frame with no options
+  }
+
   let seriesIndex = 0;
 
   if (xField.type === FieldType.time) {