subdomain fix

src/middleware.ts

@@ -4,12 +4,30 @@ import type { NextRequest } from "next/server";
 
 const isProtectedRoute = createRouteMatcher(["/dashboard(.*)", "/onboarding(.*)", "/api/publish(.*)", "/api/upload(.*)", "/api/user(.*)"]);
 
+function getSubdomain(req: NextRequest): string | null {
+  const host = req.headers.get("host");
+  if (!host) return null;
+
+  const apex = process.env.NEXT_PUBLIC_APP_DOMAIN || "testbed.mk";
+  const portIndex = host.indexOf(":");
+  const hostname = portIndex !== -1 ? host.slice(0, portIndex) : host;
+
+  if (hostname === apex || hostname === `www.${apex}`) return null;
+
+  if (hostname.endsWith(`.${apex}`)) {
+    const sub = hostname.slice(0, hostname.length - apex.length - 1);
+    if (sub && sub !== "www") return sub;
+  }
+
+  return null;
+}
+
 export default clerkMiddleware(async (auth, req: NextRequest) => {
   if (isProtectedRoute(req)) {
     await auth.protect();
   }
 
-  const subdomain = req.headers.get("x-subdomain");
+  const subdomain = getSubdomain(req);
   if (subdomain) {
     const url = req.nextUrl.clone();
     url.pathname = `/${subdomain}${url.pathname === "/" ? "" : url.pathname}`;