Next RSC: cookies().set() in validateRequest

[rwieruch]

Hi there! I have followed the Next App Router tutorial and for the validateRequest() I am setting the cookie. Everything works fine and I am able to get the current user in a server component like shown in the docs.

import { redirect } from "next/navigation";
import { validateRequest } from "@/lib/auth";

export default async function Page() {
	const { user } = await validateRequest();
	if (!user) {
		return redirect("/login");
	}
	return <h1>Hi, {user.username}!</h1>;
}

However, Next's documentation says that a query from a server component should not have side-effects vercel/next.js#49843 (comment) Is this still open for discussion or a solved topic? Thanks :)

[pilcrowOnPaper]

The cookies().set() throws an error when rendering the server component, which is patched by adding a try/catch

[rwieruch]

Okay, that's what the comment means then:

// next.js throws when you attempt to set cookie when rendering page

When does this happen though? Because in an actual application I would never want to see this error, correct?

[pilcrowOnPaper]

When rendering the page?

[rwieruch]

Now I get it. So we just swallow the error with catch {} and do nothing for RSC.

So essentially, when using validateRequest() in an RSC, we ONLY check the session without refreshing it. When using it somewhere else (e.g. server action), we do the whole thing.

[pilcrowOnPaper]

Yes, exactly