Copilot changes to improve initial load time.

src/Explorer/Tabs/Tabs.tsx

@@ -2,26 +2,48 @@ import { Spinner, SpinnerSize, TooltipHost } from "@fluentui/react";
 import { CollectionTabKind } from "Contracts/ViewModels";
 import Explorer from "Explorer/Explorer";
 import { useCommandBar } from "Explorer/Menus/CommandBar/CommandBarComponentAdapter";
-import { QueryCopilotTab } from "Explorer/QueryCopilot/QueryCopilotTab";
-import { FabricHomeScreen } from "Explorer/SplashScreen/FabricHome";
 import { SplashScreen } from "Explorer/SplashScreen/SplashScreen";
 import { ConnectTab } from "Explorer/Tabs/ConnectTab";
-import { PostgresConnectTab } from "Explorer/Tabs/PostgresConnectTab";
 import { QuickstartTab } from "Explorer/Tabs/QuickstartTab";
-import { VcoreMongoConnectTab } from "Explorer/Tabs/VCoreMongoConnectTab";
-import { VcoreMongoQuickstartTab } from "Explorer/Tabs/VCoreMongoQuickstartTab";
 import { KeyboardAction, KeyboardActionGroup, useKeyboardActionGroup } from "KeyboardShortcuts";
 import { isFabricNative } from "Platform/Fabric/FabricUtil";
 import { userContext } from "UserContext";
 import { useTeachingBubble } from "hooks/useTeachingBubble";
 import ko from "knockout";
-import React, { MutableRefObject, useEffect, useRef, useState } from "react";
+import React, { MutableRefObject, Suspense, useEffect, useRef, useState } from "react";
 import errorQuery from "../../../images/error_no_outline.svg";
 import warningIconSvg from "../../../images/warning.svg";
 import { useObservable } from "../../hooks/useObservable";
 import { ReactTabKind, useTabs } from "../../hooks/useTabs";
 import TabsBase from "./TabsBase";
 
+// Lazy-loaded tab components (code-split by API type)
+const QueryCopilotTab = React.lazy(() =>
+  import(/* webpackChunkName: "QueryCopilotTab" */ "Explorer/QueryCopilot/QueryCopilotTab").then((m) => ({
+    default: m.QueryCopilotTab,
+  })),
+);
+const FabricHomeScreen = React.lazy(() =>
+  import(/* webpackChunkName: "FabricHomeScreen" */ "Explorer/SplashScreen/FabricHome").then((m) => ({
+    default: m.FabricHomeScreen,
+  })),
+);
+const PostgresConnectTab = React.lazy(() =>
+  import(/* webpackChunkName: "PostgresConnectTab" */ "Explorer/Tabs/PostgresConnectTab").then((m) => ({
+    default: m.PostgresConnectTab,
+  })),
+);
+const VcoreMongoConnectTab = React.lazy(() =>
+  import(/* webpackChunkName: "VcoreMongoConnectTab" */ "Explorer/Tabs/VCoreMongoConnectTab").then((m) => ({
+    default: m.VcoreMongoConnectTab,
+  })),
+);
+const VcoreMongoQuickstartTab = React.lazy(() =>
+  import(/* webpackChunkName: "VcoreMongoQuickstartTab" */ "Explorer/Tabs/VCoreMongoQuickstartTab").then((m) => ({
+    default: m.VcoreMongoQuickstartTab,
+  })),
+);
+
 type Tab = TabsBase | (TabsBase & { render: () => JSX.Element });
 
 interface TabsProps {
@@ -302,30 +324,33 @@ const isQueryErrorThrown = (tab?: Tab, tabKind?: ReactTabKind): boolean => {
 };
 
 const getReactTabContent = (activeReactTab: ReactTabKind, explorer: Explorer): JSX.Element => {
-  switch (activeReactTab) {
-    case ReactTabKind.Connect:
-      return userContext.apiType === "VCoreMongo" ? (
-        <VcoreMongoConnectTab />
-      ) : userContext.apiType === "Postgres" ? (
-        <PostgresConnectTab />
-      ) : (
-        <ConnectTab />
-      );
-    case ReactTabKind.Home:
-      if (isFabricNative()) {
-        return <FabricHomeScreen explorer={explorer} />;
-      } else {
-        return <SplashScreen explorer={explorer} />;
-      }
-    case ReactTabKind.Quickstart:
-      return userContext.apiType === "VCoreMongo" ? (
-        <VcoreMongoQuickstartTab explorer={explorer} />
-      ) : (
-        <QuickstartTab explorer={explorer} />
-      );
-    case ReactTabKind.QueryCopilot:
-      return <QueryCopilotTab explorer={explorer} />;
-    default:
-      throw new Error(`Unsupported tab kind ${ReactTabKind[activeReactTab]}`);
-  }
+  const content = (() => {
+    switch (activeReactTab) {
+      case ReactTabKind.Connect:
+        return userContext.apiType === "VCoreMongo" ? (
+          <VcoreMongoConnectTab />
+        ) : userContext.apiType === "Postgres" ? (
+          <PostgresConnectTab />
+        ) : (
+          <ConnectTab />
+        );
+      case ReactTabKind.Home:
+        if (isFabricNative()) {
+          return <FabricHomeScreen explorer={explorer} />;
+        } else {
+          return <SplashScreen explorer={explorer} />;
+        }
+      case ReactTabKind.Quickstart:
+        return userContext.apiType === "VCoreMongo" ? (
+          <VcoreMongoQuickstartTab explorer={explorer} />
+        ) : (
+          <QuickstartTab explorer={explorer} />
+        );
+      case ReactTabKind.QueryCopilot:
+        return <QueryCopilotTab explorer={explorer} />;
+      default:
+        throw new Error(`Unsupported tab kind ${ReactTabKind[activeReactTab]}`);
+    }
+  })();
+  return <Suspense fallback={<Spinner size={SpinnerSize.large} />}>{content}</Suspense>;
 };

src/Explorer/Tree/Collection.ts

@@ -34,7 +34,7 @@ import Explorer from "../Explorer";
 import { useCommandBar } from "../Menus/CommandBar/CommandBarComponentAdapter";
 import { CassandraAPIDataClient, CassandraTableKey, CassandraTableKeys } from "../Tables/TableDataClient";
 import ConflictsTab from "../Tabs/ConflictsTab";
-import GraphTab from "../Tabs/GraphTab";
+import type GraphTab from "../Tabs/GraphTab";
 import { NewMongoQueryTab } from "../Tabs/MongoQueryTab/MongoQueryTab";
 import { NewMongoShellTab } from "../Tabs/MongoShellTab/MongoShellTab";
 import { NewQueryTab } from "../Tabs/QueryTab/QueryTab";
@@ -450,7 +450,7 @@ export default class Collection implements ViewModels.Collection {
     }
   }
 
-  public onGraphDocumentsClick() {
+  public async onGraphDocumentsClick() {
     useSelectedNode.getState().setSelectedNode(this);
     this.selectedSubnodeKind(ViewModels.CollectionTabKind.Graph);
     TelemetryProcessor.trace(Action.SelectItem, ActionModifiers.Mark, {
@@ -483,7 +483,8 @@ export default class Collection implements ViewModels.Collection {
         tabTitle: title,
       });
 
-      graphTab = new GraphTab({
+      const { default: GraphTabModule } = await import(/* webpackChunkName: "GraphTab" */ "../Tabs/GraphTab");
+      graphTab = new GraphTabModule({
         account: userContext.databaseAccount,
         tabKind: ViewModels.CollectionTabKind.Graph,
         node: this,
@@ -727,7 +728,7 @@ export default class Collection implements ViewModels.Collection {
     useTabs.getState().activateNewTab(newMongoQueryTab);
   }
 
-  public onNewGraphClick() {
+  public async onNewGraphClick() {
     const id: number = useTabs.getState().getTabs(ViewModels.CollectionTabKind.Graph).length + 1;
     const title: string = "Graph Query " + id;
 
@@ -739,7 +740,8 @@ export default class Collection implements ViewModels.Collection {
       tabTitle: title,
     });
 
-    const graphTab: GraphTab = new GraphTab({
+    const { default: GraphTabModule } = await import(/* webpackChunkName: "GraphTab" */ "../Tabs/GraphTab");
+    const graphTab: GraphTab = new GraphTabModule({
       account: userContext.databaseAccount,
       tabKind: ViewModels.CollectionTabKind.Graph,
       node: this,

src/Main.tsx

@@ -5,27 +5,14 @@ import "./ReactDevTools";
 import { initializeIcons, loadTheme, useTheme } from "@fluentui/react";
 import { FluentProvider, makeStyles, webDarkTheme, webLightTheme } from "@fluentui/react-components";
 import { Platform } from "ConfigContext";
-import ContainerCopyPanel from "Explorer/ContainerCopy/ContainerCopyPanel";
 import Explorer from "Explorer/Explorer";
-import { QuickstartCarousel } from "Explorer/Quickstart/QuickstartCarousel";
-import { MongoQuickstartTutorial } from "Explorer/Quickstart/Tutorials/MongoQuickstartTutorial";
-import { SQLQuickstartTutorial } from "Explorer/Quickstart/Tutorials/SQLQuickstartTutorial";
 import { userContext } from "UserContext";
 import "allotment/dist/style.css";
-import "bootstrap/dist/css/bootstrap.css";
 import { useCarousel } from "hooks/useCarousel";
 import React from "react";
 import ReactDOM from "react-dom";
-import "../externals/jquery-ui.min.css";
-import "../externals/jquery-ui.min.js";
-import "../externals/jquery-ui.structure.min.css";
-import "../externals/jquery-ui.theme.min.css";
-import "../externals/jquery.dataTables.min.css";
-import "../externals/jquery.typeahead.min.css";
-import "../externals/jquery.typeahead.min.js";
 // Image Dependencies
 import { SidePanel } from "Explorer/Panes/PanelContainerComponent";
-import { QueryCopilotCarousel } from "Explorer/QueryCopilot/CopilotCarousel";
 import { SidebarContainer } from "Explorer/Sidebar";
 import { KeyboardShortcutRoot } from "KeyboardShortcuts";
 import "allotment/dist/style.css";
@@ -72,6 +59,50 @@ import { useKnockoutExplorer } from "./hooks/useKnockoutExplorer";
 import { useThemeStore } from "./hooks/useTheme";
 import "./less/DarkModeMenus.less";
 import "./less/ThemeSystem.less";
+// Lazy-loaded components (code-split into separate chunks)
+const ContainerCopyPanel = React.lazy(
+  () => import(/* webpackChunkName: "ContainerCopyPanel" */ "Explorer/ContainerCopy/ContainerCopyPanel"),
+);
+const QuickstartCarousel = React.lazy(() =>
+  import(/* webpackChunkName: "QuickstartCarousel" */ "Explorer/Quickstart/QuickstartCarousel").then((m) => ({
+    default: m.QuickstartCarousel,
+  })),
+);
+const SQLQuickstartTutorial = React.lazy(() =>
+  import(/* webpackChunkName: "SQLQuickstartTutorial" */ "Explorer/Quickstart/Tutorials/SQLQuickstartTutorial").then(
+    (m) => ({ default: m.SQLQuickstartTutorial }),
+  ),
+);
+const MongoQuickstartTutorial = React.lazy(() =>
+  import(
+    /* webpackChunkName: "MongoQuickstartTutorial" */ "Explorer/Quickstart/Tutorials/MongoQuickstartTutorial"
+  ).then((m) => ({ default: m.MongoQuickstartTutorial })),
+);
+const QueryCopilotCarousel = React.lazy(() =>
+  import(/* webpackChunkName: "QueryCopilotCarousel" */ "Explorer/QueryCopilot/CopilotCarousel").then((m) => ({
+    default: m.QueryCopilotCarousel,
+  })),
+);
+
+// Defer loading legacy jQuery/Bootstrap CSS and JS — they are needed by Tables features, not on initial render
+const loadLegacyDependencies = () => {
+  // @ts-expect-error — side-effect-only imports handled by webpack, not real TS/ES modules
+  import(/* webpackChunkName: "legacy-styles" */ "bootstrap/dist/css/bootstrap.css");
+  // @ts-expect-error — webpack handles CSS imports
+  import(/* webpackChunkName: "legacy-styles" */ "../externals/jquery-ui.min.css");
+  // @ts-expect-error — webpack handles JS side-effect imports
+  import(/* webpackChunkName: "legacy-scripts" */ "../externals/jquery-ui.min.js");
+  // @ts-expect-error — webpack handles CSS imports
+  import(/* webpackChunkName: "legacy-styles" */ "../externals/jquery-ui.structure.min.css");
+  // @ts-expect-error — webpack handles CSS imports
+  import(/* webpackChunkName: "legacy-styles" */ "../externals/jquery-ui.theme.min.css");
+  // @ts-expect-error — webpack handles CSS imports
+  import(/* webpackChunkName: "legacy-styles" */ "../externals/jquery.dataTables.min.css");
+  // @ts-expect-error — webpack handles CSS imports
+  import(/* webpackChunkName: "legacy-styles" */ "../externals/jquery.typeahead.min.css");
+  import(/* webpackChunkName: "legacy-scripts" */ "../externals/jquery.typeahead.min.js");
+};
+
 // Initialize icons before React is loaded
 initializeIcons(undefined, { disableWarnings: true });
 
@@ -98,6 +129,8 @@ const App = (): JSX.Element => {
       import("../less/documentDBFabric.less");
     }
     StyleConstants.updateStyles();
+    // Load legacy jQuery/Bootstrap dependencies after initial render
+    loadLegacyDependencies();
   }, [config?.platform]);
 
   const explorer = useKnockoutExplorer(config?.platform);
@@ -131,11 +164,11 @@ const App = (): JSX.Element => {
       <KeyboardShortcutRoot>
         <div className="flexContainer" aria-hidden="false">
           {userContext.features.enableContainerCopy && userContext.apiType === "SQL" ? (
-            <>
+            <React.Suspense fallback={null}>
               <ContainerCopyPanel explorer={explorer} />
               <SidePanel />
               <Dialog />
-            </>
+            </React.Suspense>
           ) : (
             <DivExplorer explorer={explorer} />
           )}
@@ -191,10 +224,12 @@ const DivExplorer: React.FC<{ explorer: Explorer }> = ({ explorer }) => {
       </div>
       <SidePanel />
       <Dialog />
-      {<QuickstartCarousel isOpen={isCarouselOpen} />}
-      {<SQLQuickstartTutorial />}
-      {<MongoQuickstartTutorial />}
-      {<QueryCopilotCarousel isOpen={isCopilotCarouselOpen} explorer={explorer} />}
+      <React.Suspense fallback={null}>
+        {<QuickstartCarousel isOpen={isCarouselOpen} />}
+        {<SQLQuickstartTutorial />}
+        {<MongoQuickstartTutorial />}
+        {<QueryCopilotCarousel isOpen={isCopilotCarouselOpen} explorer={explorer} />}
+      </React.Suspense>
     </div>
   );
 };

webpack.config.js

@@ -123,7 +123,7 @@ module.exports = function (_env = {}, argv = {}) {
     new HtmlWebpackPlugin({
       filename: "explorer.html",
       template: "src/explorer.html",
-      chunks: ["main"],
+      chunks: ["main", "vendor", "vendor-fluentui", "vendor-nteract"],
     }),
     new HtmlWebpackPlugin({
       filename: "terminal.html",
@@ -262,6 +262,30 @@ module.exports = function (_env = {}, argv = {}) {
           },
         }),
       ],
+      splitChunks: {
+        chunks: "all",
+        maxInitialRequests: 10,
+        cacheGroups: {
+          fluentui: {
+            test: /[\\/]node_modules[\\/]@fluentui[\\/]/,
+            name: "vendor-fluentui",
+            chunks: "all",
+            priority: 30,
+          },
+          nteract: {
+            test: /[\\/]node_modules[\\/]@nteract[\\/]/,
+            name: "vendor-nteract",
+            chunks: "all",
+            priority: 30,
+          },
+          vendor: {
+            test: /[\\/]node_modules[\\/]/,
+            name: "vendor",
+            chunks: "all",
+            priority: 10,
+          },
+        },
+      },
     },
     watch: false,
     // Hack since it is hard to disable watch entirely with webpack dev server https://github.com/webpack/webpack-dev-server/issues/1251#issuecomment-654240734