Add ZITADEL auth and hello world page

app/api/auth/[...nextauth]/route.ts

@@ -0,0 +1,2 @@
+import { handlers } from "@/auth"
+export const { GET, POST } = handlers

app/layout.tsx

@@ -13,8 +13,8 @@ const geistMono = Geist_Mono({
 });
 
 export const metadata: Metadata = {
-  title: "Create Next App",
+  title: "Demo",
-  description: "Generated by create next app",
+  description: "NextAuth.js + ZITADEL demo",
 };
 
 export default function RootLayout({

app/page.tsx

@@ -1,65 +1,46 @@
-import Image from "next/image";
+import { auth, signIn, signOut } from "@/auth"
+
+export default async function Home() {
+  const session = await auth()
 
-export default function Home() {
   return (
-    <div className="flex flex-col flex-1 items-center justify-center bg-zinc-50 font-sans dark:bg-black">
+    <div className="flex min-h-screen items-center justify-center bg-zinc-50 dark:bg-black">
-      <main className="flex flex-1 w-full max-w-3xl flex-col items-center justify-between py-32 px-16 bg-white dark:bg-black sm:items-start">
+      <main className="flex flex-col items-center gap-6 rounded-2xl bg-white px-12 py-10 shadow-sm dark:bg-zinc-900">
-        <Image
+        {session ? (
-          className="dark:invert"
+          <>
-          src="/next.svg"
+            <p className="text-2xl font-semibold text-zinc-900 dark:text-zinc-50">
-          alt="Next.js logo"
+              Hello, {session.user?.name}!
-          width={100}
+            </p>
-          height={20}
+            <form
-          priority
+              action={async () => {
-        />
+                "use server"
-        <div className="flex flex-col items-center gap-6 text-center sm:items-start sm:text-left">
+                await signOut({ redirectTo: "/" })
-          <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"
             >
-              Templates
+              <button
-            </a>{" "}
+                type="submit"
-            or the{" "}
+                className="rounded-full bg-zinc-900 px-6 py-2 text-sm font-medium text-white transition-colors hover:bg-zinc-700 dark:bg-zinc-100 dark:text-zinc-900 dark:hover:bg-zinc-300"
-            <a
+              >
-              href="https://nextjs.org/learn?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
+                Logout
-              className="font-medium text-zinc-950 dark:text-zinc-50"
+              </button>
+            </form>
+          </>
+        ) : (
+          <form
+            action={async () => {
+              "use server"
+              await signIn("zitadel")
+            }}
+          >
+            <button
+              type="submit"
+              className="rounded-full bg-zinc-900 px-6 py-2 text-sm font-medium text-white transition-colors hover:bg-zinc-700 dark:bg-zinc-100 dark:text-zinc-900 dark:hover:bg-zinc-300"
             >
-              Learning
+              Login
-            </a>{" "}
+            </button>
-            center.
+          </form>
-          </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>
       </main>
     </div>
-  );
+  )
 }

auth.ts

@@ -0,0 +1,31 @@
+import NextAuth from "next-auth"
+import ZITADEL from "next-auth/providers/zitadel"
+
+export const { handlers, auth, signIn, signOut } = NextAuth({
+  providers: [
+    ZITADEL({
+      clientId: process.env.ZITADEL_CLIENT_ID!,
+      clientSecret: process.env.ZITADEL_CLIENT_SECRET!,
+      issuer: process.env.ZITADEL_ISSUER,
+    }),
+  ],
+  callbacks: {
+    async jwt({ token, account }) {
+      // account is only present on the initial sign-in
+      if (account?.access_token) {
+        const res = await fetch(
+          `${process.env.ZITADEL_ISSUER}/oidc/v1/userinfo`,
+          { headers: { Authorization: `Bearer ${account.access_token}` } }
+        )
+        const userinfo = await res.json()
+        console.log("[auth] ZITADEL userinfo:", JSON.stringify(userinfo, null, 2))
+        token.name = userinfo.name ?? userinfo.preferred_username ?? token.name
+      }
+      return token
+    },
+    session({ session, token }) {
+      if (token.name) session.user.name = token.name as string
+      return session
+    },
+  },
+})

package-lock.json

@@ -9,6 +9,7 @@
       "version": "0.1.0",
       "dependencies": {
         "next": "16.2.4",
+        "next-auth": "^5.0.0-beta.31",
         "react": "19.2.4",
         "react-dom": "19.2.4"
       },
@@ -36,6 +37,35 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/@auth/core": {
+      "version": "0.41.2",
+      "resolved": "https://registry.npmjs.org/@auth/core/-/core-0.41.2.tgz",
+      "integrity": "sha512-Hx5MNBxN2fJTbJKGUKAA0wca43D0Akl3TvufY54Gn8lop7F+34vU1zA1pn0vQfIoVuLIrpfc2nkyjwIaPJMW7w==",
+      "license": "ISC",
+      "dependencies": {
+        "@panva/hkdf": "^1.2.1",
+        "jose": "^6.0.6",
+        "oauth4webapi": "^3.3.0",
+        "preact": "10.24.3",
+        "preact-render-to-string": "6.5.11"
+      },
+      "peerDependencies": {
+        "@simplewebauthn/browser": "^9.0.1",
+        "@simplewebauthn/server": "^9.0.2",
+        "nodemailer": "^7.0.7"
+      },
+      "peerDependenciesMeta": {
+        "@simplewebauthn/browser": {
+          "optional": true
+        },
+        "@simplewebauthn/server": {
+          "optional": true
+        },
+        "nodemailer": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/@babel/code-frame": {
       "version": "7.29.0",
       "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.29.0.tgz",
@@ -1286,6 +1316,15 @@
         "node": ">=12.4.0"
       }
     },
+    "node_modules/@panva/hkdf": {
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/@panva/hkdf/-/hkdf-1.2.1.tgz",
+      "integrity": "sha512-6oclG6Y3PiDFcoyk8srjLfVKyMfVCKJ27JwNPViuXziFpmdz+MZnZN/aKY0JGXgYuO/VghU0jcOAZgWXZ1Dmrw==",
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/panva"
+      }
+    },
     "node_modules/@rtsao/scc": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/@rtsao/scc/-/scc-1.1.0.tgz",
@@ -4506,6 +4545,15 @@
         "jiti": "lib/jiti-cli.mjs"
       }
     },
+    "node_modules/jose": {
+      "version": "6.2.2",
+      "resolved": "https://registry.npmjs.org/jose/-/jose-6.2.2.tgz",
+      "integrity": "sha512-d7kPDd34KO/YnzaDOlikGpOurfF0ByC2sEV4cANCtdqLlTfBlw2p14O/5d/zv40gJPbIQxfES3nSx1/oYNyuZQ==",
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/panva"
+      }
+    },
     "node_modules/js-tokens": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/js-tokens/-/js-tokens-4.0.0.tgz",
@@ -5120,6 +5168,33 @@
         }
       }
     },
+    "node_modules/next-auth": {
+      "version": "5.0.0-beta.31",
+      "resolved": "https://registry.npmjs.org/next-auth/-/next-auth-5.0.0-beta.31.tgz",
+      "integrity": "sha512-1OBgCKPzo+S7UWWMp3xgvGvIJ0OpV7B3vR4ZDRqD9a4Ch+OT6dakLXG9ivhtmIWVa71nTSXattOHyCg8sNi8/Q==",
+      "license": "ISC",
+      "dependencies": {
+        "@auth/core": "0.41.2"
+      },
+      "peerDependencies": {
+        "@simplewebauthn/browser": "^9.0.1",
+        "@simplewebauthn/server": "^9.0.2",
+        "next": "^14.0.0-0 || ^15.0.0 || ^16.0.0",
+        "nodemailer": "^7.0.7",
+        "react": "^18.2.0 || ^19.0.0"
+      },
+      "peerDependenciesMeta": {
+        "@simplewebauthn/browser": {
+          "optional": true
+        },
+        "@simplewebauthn/server": {
+          "optional": true
+        },
+        "nodemailer": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/next/node_modules/postcss": {
       "version": "8.4.31",
       "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.31.tgz",
@@ -5174,6 +5249,15 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/oauth4webapi": {
+      "version": "3.8.5",
+      "resolved": "https://registry.npmjs.org/oauth4webapi/-/oauth4webapi-3.8.5.tgz",
+      "integrity": "sha512-A8jmyUckVhRJj5lspguklcl90Ydqk61H3dcU0oLhH3Yv13KpAliKTt5hknpGGPZSSfOwGyraNEFmofDYH+1kSg==",
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/panva"
+      }
+    },
     "node_modules/object-assign": {
       "version": "4.1.1",
       "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
@@ -5463,6 +5547,25 @@
         "node": "^10 || ^12 || >=14"
       }
     },
+    "node_modules/preact": {
+      "version": "10.24.3",
+      "resolved": "https://registry.npmjs.org/preact/-/preact-10.24.3.tgz",
+      "integrity": "sha512-Z2dPnBnMUfyQfSQ+GBdsGa16hz35YmLmtTLhM169uW944hYL6xzTYkJjC07j+Wosz733pMWx0fgON3JNw1jJQA==",
+      "license": "MIT",
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/preact"
+      }
+    },
+    "node_modules/preact-render-to-string": {
+      "version": "6.5.11",
+      "resolved": "https://registry.npmjs.org/preact-render-to-string/-/preact-render-to-string-6.5.11.tgz",
+      "integrity": "sha512-ubnauqoGczeGISiOh6RjX0/cdaF8v/oDXIjO85XALCQjwQP+SB4RDXXtvZ6yTYSjG+PC1QRP2AhPgCEsM2EvUw==",
+      "license": "MIT",
+      "peerDependencies": {
+        "preact": ">=10"
+      }
+    },
     "node_modules/prelude-ls": {
       "version": "1.2.1",
       "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.2.1.tgz",

package.json

@@ -10,6 +10,7 @@
   },
   "dependencies": {
     "next": "16.2.4",
+    "next-auth": "^5.0.0-beta.31",
     "react": "19.2.4",
     "react-dom": "19.2.4"
   },