FEAT: multidomain support

nextauthjs/next-auth#10928 (comment)

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

@@ -1,2 +1,22 @@
 import { handlers } from "@/lib/auth";
-export const { GET, POST } = handlers;
+import { NextRequest } from "next/server";
+
+const reqWithTrustedOrigin = (req: NextRequest): NextRequest => {
+	const proto = req.headers.get("x-forwarded-proto");
+	const host = req.headers.get("x-forwarded-host");
+	if (!proto || !host) {
+		console.warn("Missing x-forwarded-proto or x-forwarded-host headers.");
+		return req;
+	}
+	const envOrigin = `${proto}://${host}`;
+	const { href, origin } = req.nextUrl;
+	return new NextRequest(href.replace(origin, envOrigin), req);
+};
+
+export const GET = (req: NextRequest) => {
+	return handlers.GET(reqWithTrustedOrigin(req));
+};
+
+export const POST = (req: NextRequest) => {
+	return handlers.POST(reqWithTrustedOrigin(req));
+};