Fix broker stats

app/src/components/ChartPanel/ChartWithTreeNode.tsx

@@ -1,7 +1,8 @@
 import * as q from '../../../../backend/src/Model'
-import * as React from 'react'
+import React from 'react'
 import Chart from './Chart'
 import { ChartParameters } from '../../reducers/Charts'
+import { usePollingToFetchTreeNode } from '../helper/usePollingToFetchTreeNode'
 
 interface Props {
   tree?: q.Tree<any>
@@ -14,37 +15,6 @@ export function ChartWithTreeNode(props: Props) {
     return null
   }
 
-  const initialTreeNode = tree.findNode(parameters.topic)
-  const [treeNode, setTreeNode] = React.useState<q.TreeNode<any> | undefined>(initialTreeNode)
-
-  usePollingToFetchTreeNode(treeNode, tree, parameters.topic, setTreeNode)
+  const treeNode = usePollingToFetchTreeNode(tree, parameters.topic)
   return <Chart treeNode={treeNode} parameters={parameters} />
 }
-
-/**
- * If a node is not available when the plot is shown, keep polling until it has been created
- */
-function usePollingToFetchTreeNode(
-  treeNode: q.TreeNode<any> | undefined,
-  tree: q.Tree<any>,
-  path: string,
-  setTreeNode: React.Dispatch<React.SetStateAction<q.TreeNode<any> | undefined>>
-) {
-  function pollUntilTreeNodeHasBeenFound() {
-    let intervalTimer: any
-    if (!treeNode) {
-      intervalTimer = setInterval(() => {
-        const node = tree.findNode(path)
-        if (node) {
-          setTreeNode(node)
-          clearInterval(intervalTimer)
-        }
-      }, 500)
-    }
-    return function cleanup() {
-      intervalTimer && clearInterval(intervalTimer)
-    }
-  }
-
-  React.useEffect(pollUntilTreeNodeHasBeenFound, [])
-}