Option to prerender 404 page

[GitRowin]

Describe the problem

I am using the static adapter. The recommended way to generate a 404 page seems to be by using the fallback option, however, this option is meant to be used to generate a SPA, so it outputs a blank HTML page. I would like my 404 page to be prerendered.

Describe the proposed solution

I propose adding an option to adapter-static to generate a prerendered 404 page.

Alternatives considered

I tried simply creating 404/+page.svelte. There are two problems with this approach:

1. It doesn't work during development, because the server renders +error.svelte.
2. It doesn't work when serving the file from a subdirectory, because SvelteKit uses relative paths to assets.

Problem 1 can be solved by turning the 404 page into a component and rendering it in both 404/+page.svelte and +error.svelte.

Problem 2 can be solved by setting kit.paths.relative to false.

This feels quite hacky though.

Importance

nice to have

Additional Information

No response

[teemingc]

I tried simply creating 404/+page.svelte. There are two problems with this approach: It doesn't work during development, because the server renders +error.svelte.

You can mock a redirect to your 404 page during development with the following hook:

src/hooks.server.js

import { redirect } from '@sveltejs/kit';

/** @type {import('@sveltejs/kit').Handle} */
export async function handle({ event, resolve }) {
	const response = await resolve(event);
	if (response.status === 404) {
		throw redirect(307, '/404');
	}
	return response;
}