next-auth.js Auth Middleware for Next.js 12.2

middleware.ts

import { NextResponse, type NextRequest } from "next/server";
import { getToken } from "next-auth/jwt";

export const config = { matcher: "/", runtime: "experimental-edge" };

/**
 * This middleware ensures auth on all routes.
 * The file should be placed in the root directory of the project.
 * E.g., /middleware.ts, or /src/middleware.ts
 *
 */

const secret = process.env.NEXTAUTH_SECRET;

export default async function middleware(nextRequest: NextRequest) {
  const absoluteURL = (_: "/login" | "/") => new URL(_, nextRequest.url);

  const token = await getToken({
    req: nextRequest,
    secret: process.env.NEXTAUTH_SECRET,
    secureCookie: process.env.NODE_ENV === "production",
  });

  if (!token) return NextResponse.rewrite(absoluteURL("/login"));
  return NextResponse.rewrite(absoluteURL("/"));
}