Use Middleware for Simple Auth Redirect

Next.js

JavaScript

Technical Specification

Use middleware.ts to protect a dashboard route and redirect to login if no cookie is set.

Input/Output Samples

Input:visit /dashboard without auth cookie

Output:redirect to /login

Optimal Logic Path

import { NextResponse } from "next/server";

export function middleware(request) {
  const hasAuth = request.cookies.get("auth_token");
  if (!hasAuth && request.nextUrl.pathname.startsWith("/dashboard")) {
    const url = new URL("/login", request.url);
    return NextResponse.redirect(url);
  }
  return NextResponse.next();
}

Architectural Deep-Dive

Middleware runs before the route and can redirect based on cookies or headers.