refactor(ui): adopt shared tab-routing helpers + anchor TabRouteBar in Caching

Now that createTabRoutes and useTabRouting are on staging, replace
Caching's hand-written tabRoutes.ts and layout routing engine with them,
and introduce the shared <TabRouteBar>: a shadcn tab bar whose triggers
render as real anchors (via Base UI's render prop). A plain left click
soft-navigates through the router; a modifier-click falls through to the
browser so open-in-new-tab / new-window work, mirroring the sidebar's
own anchor convention. tabRoutes.ts collapses to one createTabRoutes
call and the per-page tabRoutes.test.ts is dropped (the factory is
covered centrally by utils/tabRoutes.test.ts).

ui/litellm-dashboard/src/app/(dashboard)/caching/layout.test.tsx

@@ -33,30 +33,24 @@ describe("CachingLayout", () => {
     };
   });
 
-  it("renders the tab bar and the active tab's page content", () => {
+  it("renders the four tabs and the active tab's page content", () => {
     const { getByRole, getByTestId } = renderLayout();
-    expect(getByRole("tab", { name: "Cache Analytics" })).toBeInTheDocument();
-    expect(getByRole("tab", { name: "Cache Health" })).toBeInTheDocument();
-    expect(getByRole("tab", { name: "Cache Settings" })).toBeInTheDocument();
-    expect(getByRole("tab", { name: "Coordination Redis" })).toBeInTheDocument();
+    for (const name of ["Cache Analytics", "Cache Health", "Cache Settings", "Coordination Redis"]) {
+      expect(getByRole("tab", { name })).toBeInTheDocument();
+    }
     expect(getByTestId("tab-content")).toHaveTextContent("CHILD");
   });
 
-  it("navigates to a tab's path when its tab is clicked", async () => {
+  it("marks the base route's Cache Analytics tab active", () => {
     const { getByRole } = renderLayout();
-    await act(async () => {
-      getByRole("tab", { name: "Cache Health" }).click();
-    });
-    expect(mockPush).toHaveBeenCalledWith(expect.stringMatching(/\/caching\/health\/$/));
+    expect(getByRole("tab", { name: "Cache Analytics" })).toHaveAttribute("aria-selected", "true");
   });
 
-  it("routes the base tab back to the caching root (no slug)", async () => {
-    navState.pathname = "/caching/health";
+  it("derives the active tab from a nested pathname", () => {
+    navState.pathname = "/ui/caching/settings";
     const { getByRole } = renderLayout();
-    await act(async () => {
-      getByRole("tab", { name: "Cache Analytics" }).click();
-    });
-    expect(mockPush).toHaveBeenCalledWith(expect.stringMatching(/\/caching\/$/));
+    expect(getByRole("tab", { name: "Cache Settings" })).toHaveAttribute("aria-selected", "true");
+    expect(getByRole("tab", { name: "Cache Analytics" })).toHaveAttribute("aria-selected", "false");
   });
 
   it("redirects to the base caching path when the tab slug is unknown", async () => {

ui/litellm-dashboard/src/app/(dashboard)/caching/layout.tsx

@@ -1,48 +1,29 @@
 "use client";
 
 import type { ReactNode } from "react";
-import { useEffect } from "react";
-import { usePathname, useRouter } from "next/navigation";
-import { Tabs, TabsList, TabsTrigger } from "@/components/ui/tabs";
-import { cacheTabHref, slugFromPathname, type CacheTabSlug } from "@/app/(dashboard)/caching/tabRoutes";
+import { cachingRoutes } from "@/app/(dashboard)/caching/tabRoutes";
+import { useTabRouting } from "@/app/(dashboard)/hooks/useTabRouting";
+import { TabRouteBar } from "@/app/(dashboard)/components/TabRouteBar";
 
 const BASE_TAB_KEY = "cache-analytics";
 
-const ORDERED_KEYS: Array<"" | CacheTabSlug> = ["", "health", "settings", "coordination-redis"];
-
-const TAB_LABELS: Record<"" | CacheTabSlug, string> = {
-  "": "Cache Analytics",
-  health: "Cache Health",
-  settings: "Cache Settings",
-  "coordination-redis": "Coordination Redis",
-};
+const TABS = [
+  { key: BASE_TAB_KEY, label: "Cache Analytics" },
+  { key: "health", label: "Cache Health" },
+  { key: "settings", label: "Cache Settings" },
+  { key: "coordination-redis", label: "Coordination Redis" },
+] as const;
 
 export default function CachingLayout({ children }: { children: ReactNode }) {
-  const pathname = usePathname();
-  const router = useRouter();
-
-  const activeSlug = slugFromPathname(pathname);
-  const isKnownSlug = ORDERED_KEYS.some((slug) => slug === activeSlug);
-  const activeKey = isKnownSlug ? activeSlug || BASE_TAB_KEY : BASE_TAB_KEY;
-
-  useEffect(() => {
-    if (activeSlug !== "" && !isKnownSlug) {
-      window.location.replace(cacheTabHref(""));
-    }
-  }, [activeSlug, isKnownSlug]);
+  const { activeKey } = useTabRouting({
+    routes: cachingRoutes,
+    baseTabKey: BASE_TAB_KEY,
+    visibleKeys: cachingRoutes.slugs,
+  });
 
   return (
     <div className="p-8 w-full mt-2 mb-8">
-      <Tabs value={activeKey} onValueChange={(key) => router.push(cacheTabHref(key === BASE_TAB_KEY ? "" : key))}>
-        <TabsList variant="line">
-          {ORDERED_KEYS.map((slug) => (
-            <TabsTrigger key={slug || BASE_TAB_KEY} value={slug || BASE_TAB_KEY}>
-              {TAB_LABELS[slug]}
-            </TabsTrigger>
-          ))}
-        </TabsList>
-      </Tabs>
-
+      <TabRouteBar routes={cachingRoutes} baseTabKey={BASE_TAB_KEY} activeKey={activeKey} tabs={TABS} />
       <div className="mt-4">{children}</div>
     </div>
   );

ui/litellm-dashboard/src/app/(dashboard)/caching/tabRoutes.test.ts

@@ -1,38 +0,0 @@
-/* @vitest-environment jsdom */
-import { describe, expect, it, vi } from "vitest";
-
-vi.mock("@/components/networking", () => ({ serverRootPath: "" }));
-
-import { CACHE_TAB_SLUGS, cacheTabHref, slugFromPathname } from "./tabRoutes";
-
-describe("slugFromPathname", () => {
-  it("returns empty string for the base path with or without a trailing slash", () => {
-    expect(slugFromPathname("/caching")).toBe("");
-    expect(slugFromPathname("/caching/")).toBe("");
-  });
-
-  it("extracts the tab slug from dev and proxy-mounted (/ui) paths", () => {
-    expect(slugFromPathname("/caching/health")).toBe("health");
-    expect(slugFromPathname("/ui/caching/coordination-redis/")).toBe("coordination-redis");
-  });
-
-  it("returns the raw segment for an unknown tab so the layout can redirect to base", () => {
-    expect(slugFromPathname("/ui/caching/bogus")).toBe("bogus");
-  });
-
-  it("returns empty string when the caching base segment is not in the path", () => {
-    expect(slugFromPathname("/teams")).toBe("");
-  });
-});
-
-describe("cacheTabHref", () => {
-  it("builds the trailing-slash base href for the empty slug", () => {
-    expect(cacheTabHref("")).toBe("/ui/caching/");
-  });
-
-  it("builds a trailing-slash href for every tab slug (required by static export)", () => {
-    for (const slug of CACHE_TAB_SLUGS) {
-      expect(cacheTabHref(slug)).toBe(`/ui/caching/${slug}/`);
-    }
-  });
-});

ui/litellm-dashboard/src/app/(dashboard)/caching/tabRoutes.ts

@@ -1,21 +1,5 @@
-import { migratedHref } from "@/utils/migratedPages";
+import { createTabRoutes } from "@/utils/tabRoutes";
 
-export const CACHING_BASE_SEGMENT = "caching";
+export const cachingRoutes = createTabRoutes("caching", ["health", "settings", "coordination-redis"] as const);
 
-export const CACHE_TAB_SLUGS = ["health", "settings", "coordination-redis"] as const;
-
-export type CacheTabSlug = (typeof CACHE_TAB_SLUGS)[number];
-
-export function cacheTabHref(slug: string): string {
-  const base = migratedHref(CACHING_BASE_SEGMENT);
-  return slug ? `${base}/${slug}/` : `${base}/`;
-}
-
-export function slugFromPathname(pathname: string): string {
-  const parts = pathname.split("/").filter(Boolean);
-  const idx = parts.indexOf(CACHING_BASE_SEGMENT);
-  if (idx === -1) {
-    return "";
-  }
-  return parts[idx + 1] ?? "";
-}
+export type CacheTabSlug = (typeof cachingRoutes.slugs)[number];

ui/litellm-dashboard/src/app/(dashboard)/components/TabRouteBar.test.tsx

@@ -0,0 +1,56 @@
+/* @vitest-environment jsdom */
+import { render } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const { mockPush } = vi.hoisted(() => ({ mockPush: vi.fn() }));
+vi.mock("next/navigation", () => ({ useRouter: () => ({ push: mockPush }) }));
+vi.mock("@/components/networking", () => ({ serverRootPath: "" }));
+
+import { createTabRoutes } from "@/utils/tabRoutes";
+import { TabRouteBar } from "./TabRouteBar";
+
+const routes = createTabRoutes("caching", ["health", "settings"] as const);
+const TABS = [
+  { key: "analytics", label: "Cache Analytics" },
+  { key: "health", label: "Cache Health" },
+  { key: "settings", label: "Cache Settings" },
+];
+
+const renderBar = (activeKey = "analytics") =>
+  render(<TabRouteBar routes={routes} baseTabKey="analytics" activeKey={activeKey} tabs={TABS} />);
+
+describe("TabRouteBar", () => {
+  beforeEach(() => {
+    mockPush.mockClear();
+  });
+
+  it("renders each tab as an anchor with its trailing-slash href (base tab maps to the root)", () => {
+    const { getByRole } = renderBar();
+    expect(getByRole("tab", { name: "Cache Analytics" })).toHaveAttribute("href", "/ui/caching/");
+    expect(getByRole("tab", { name: "Cache Health" })).toHaveAttribute("href", "/ui/caching/health/");
+    expect(getByRole("tab", { name: "Cache Settings" })).toHaveAttribute("href", "/ui/caching/settings/");
+  });
+
+  it("marks the active tab selected from activeKey", () => {
+    const { getByRole } = renderBar("health");
+    expect(getByRole("tab", { name: "Cache Health" })).toHaveAttribute("aria-selected", "true");
+    expect(getByRole("tab", { name: "Cache Analytics" })).toHaveAttribute("aria-selected", "false");
+  });
+
+  it("soft-navigates on a plain left click (preventing the full-page anchor load)", async () => {
+    const user = userEvent.setup();
+    const { getByRole } = renderBar();
+    await user.click(getByRole("tab", { name: "Cache Health" }));
+    expect(mockPush).toHaveBeenCalledWith("/ui/caching/health/");
+  });
+
+  it("lets the browser handle a modifier-click so open-in-new-tab works", async () => {
+    const user = userEvent.setup();
+    const { getByRole } = renderBar();
+    await user.keyboard("[ControlLeft>]");
+    await user.click(getByRole("tab", { name: "Cache Health" }));
+    await user.keyboard("[/ControlLeft]");
+    expect(mockPush).not.toHaveBeenCalled();
+  });
+});

ui/litellm-dashboard/src/app/(dashboard)/components/TabRouteBar.tsx

@@ -0,0 +1,48 @@
+"use client";
+
+import type { MouseEvent } from "react";
+import { useRouter } from "next/navigation";
+import { Tabs, TabsList, TabsTrigger } from "@/components/ui/tabs";
+import type { TabRoutes } from "@/utils/tabRoutes";
+
+export interface TabRouteItem {
+  key: string;
+  label: string;
+}
+
+interface TabRouteBarProps {
+  routes: Pick<TabRoutes<string>, "tabHref">;
+  baseTabKey: string;
+  activeKey: string;
+  tabs: readonly TabRouteItem[];
+  className?: string;
+}
+
+export function TabRouteBar({ routes, baseTabKey, activeKey, tabs, className }: TabRouteBarProps) {
+  const router = useRouter();
+
+  const navigate = (href: string) => (event: MouseEvent<HTMLAnchorElement>) => {
+    const commandModifier = event.metaKey || event.ctrlKey;
+    const otherModifier = event.shiftKey || event.altKey;
+    if (commandModifier || otherModifier) {
+      return;
+    }
+    event.preventDefault();
+    router.push(href);
+  };
+
+  return (
+    <Tabs value={activeKey} className={className}>
+      <TabsList variant="line">
+        {tabs.map(({ key, label }) => {
+          const href = routes.tabHref(key === baseTabKey ? "" : key);
+          return (
+            <TabsTrigger key={key} value={key} render={<a href={href} onClick={navigate(href)} />}>
+              {label}
+            </TabsTrigger>
+          );
+        })}
+      </TabsList>
+    </Tabs>
+  );
+}