docs: added search track event (#2051)

* added search track event

* handle all search inputs events

www/docs/src/theme/SearchBar/index.js

@@ -1,7 +1,39 @@
-import React from 'react';
+import React, { useEffect } from 'react';
+
 import SearchBar from '@theme-original/SearchBar';
+import useIsBrowser from '@docusaurus/useIsBrowser';
+import {useLocation} from '@docusaurus/router';
 
 export default function SearchBarWrapper(props) {
+
+  const isBrowser = useIsBrowser();
+  const location = useLocation();
+
+  useEffect(() => {
+    if (isBrowser) {
+
+      function trackSearch(e) {
+        if (!e.target.classList.contains('DocSearch-Input') && !(e.target.tagName.toLowerCase() === "input" && e.target.getAttribute('type') === 'search')) {
+          return;
+        }
+  
+        const query = e.target.value;
+        if (query.length >= 3) {
+          //send event to segment
+          window.analytics.track('search', {
+            query
+          });
+        }
+      }
+
+      document.body.addEventListener('keyup', trackSearch);
+
+      return () => {
+        document.body.removeEventListener('keyup', trackSearch);
+      }
+    }
+  }, [isBrowser, location.pathname]);
+
   return (
     <>
       <SearchBar {...props} />