Tested KeyCloak validation - AUTH

Test Keycloak JWT validation against access token issued via NextAuth; ensure Spring Boot resource server correctly validates token signature, expiration, issuer, and optional audience.

frontend/src/app/page.tsx

@@ -1,65 +1,50 @@
-import Image from "next/image";
+import { getServerSession } from "next-auth";
+import Link from "next/link";
+
+import { authOptions } from "@/lib/auth";
+import { signOut } from "next-auth/react";
+
+export default async function Home() {
+  const session = await getServerSession(authOptions);
 
-export default function Home() {
   return (
-    <div className="flex min-h-screen items-center justify-center bg-zinc-50 font-sans dark:bg-black">
-      <main className="flex min-h-screen w-full max-w-3xl flex-col items-center justify-between py-32 px-16 bg-white dark:bg-black sm:items-start">
-        <Image
-          className="dark:invert"
-          src="/next.svg"
-          alt="Next.js logo"
-          width={100}
-          height={20}
-          priority
-        />
-        <div className="flex flex-col items-center gap-6 text-center sm:items-start sm:text-left">
-          <h1 className="max-w-xs text-3xl font-semibold leading-10 tracking-tight text-black dark:text-zinc-50">
-            To get started, edit the page.tsx file.
-          </h1>
-          <p className="max-w-md text-lg leading-8 text-zinc-600 dark:text-zinc-400">
-            Looking for a starting point or more instructions? Head over to{" "}
-            <a
-              href="https://vercel.com/templates?framework=next.js&utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-              className="font-medium text-zinc-950 dark:text-zinc-50"
+    <main className="mx-auto flex min-h-screen w-full max-w-3xl flex-col justify-center gap-6 px-6 py-20">
+      <h1 className="text-3xl font-semibold tracking-tight">EnvSync Auth Example</h1>
+
+      <div className="rounded-xl border border-black/10 p-6 dark:border-white/20">
+        {session ? (
+          <>
+            <p className="text-sm text-zinc-600 dark:text-zinc-300">Signed in as</p>
+            <p className="mt-1 text-lg font-medium">{session.user?.email ?? session.user?.name ?? "Keycloak user"}</p>
+            <Link
+              className="mt-4 inline-flex h-10 items-center rounded-md bg-black px-4 text-sm font-medium text-white dark:bg-white dark:text-black"
+              href={"/api/auth/signout"}
             >
-              Templates
-            </a>{" "}
-            or the{" "}
-            <a
-              href="https://nextjs.org/learn?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-              className="font-medium text-zinc-950 dark:text-zinc-50"
+              Sign out
+            </Link>
+          </>
+        ) : (
+          <>
+            <p className="text-sm text-zinc-600 dark:text-zinc-300">You are not signed in.</p>
+            <Link
+              className="mt-4 inline-flex h-10 items-center rounded-md bg-black px-4 text-sm font-medium text-white dark:bg-white dark:text-black"
+              href="/api/auth/signin/keycloak"
             >
-              Learning
-            </a>{" "}
-            center.
-          </p>
-        </div>
-        <div className="flex flex-col gap-4 text-base font-medium sm:flex-row">
-          <a
-            className="flex h-12 w-full items-center justify-center gap-2 rounded-full bg-foreground px-5 text-background transition-colors hover:bg-[#383838] dark:hover:bg-[#ccc] md:w-[158px]"
-            href="https://vercel.com/new?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-            target="_blank"
-            rel="noopener noreferrer"
-          >
-            <Image
-              className="dark:invert"
-              src="/vercel.svg"
-              alt="Vercel logomark"
-              width={16}
-              height={16}
-            />
-            Deploy Now
-          </a>
-          <a
-            className="flex h-12 w-full items-center justify-center rounded-full border border-solid border-black/[.08] px-5 transition-colors hover:border-transparent hover:bg-black/[.04] dark:border-white/[.145] dark:hover:bg-[#1a1a1a] md:w-[158px]"
-            href="https://nextjs.org/docs?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-            target="_blank"
-            rel="noopener noreferrer"
-          >
-            Documentation
-          </a>
-        </div>
+              Sign in with Keycloak
+            </Link>
+          </>
+        )}
+      </div>
+
+      <div className="flex gap-3">
+        <Link className="rounded-md border border-black/10 px-4 py-2 text-sm dark:border-white/20" href="/server">
+          /server example
+        </Link>
+        <Link className="rounded-md border border-black/10 px-4 py-2 text-sm dark:border-white/20" href="/client">
+          /client example
+        </Link>
+      </div>
       </main>
-    </div>
+
   );
 }