handle doc 404s

[Rich-Harris]

Received a report that a link to /docs/typescript was 500ing rather than 404ing. This fixes it. An alternative/additional fix would be to set up redirects every time we make a change to the structure of the docs, but I think that would be a bad use of time at least until 1.0

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[Rich-Harris]

Gah, it doesn't fix it. If you try to hit a non-prerendered page, it will fall back to the serverless function, which attempts to read a non-existent file from the filesystem. Might have to do a gross workaround

[Conduitry]

There was an issue opened for this recently, which I was having trouble finding. Turns out because it was opened in the Svelte repo. I've moved it here: #4086.

[Rich-Harris]

So... we could certainly work around this, but it wouldn't be that pretty, and it would just be masking the real issue which is that the endpoint shouldn't be deployed anyway.

I think the solution is to add export const prerendered to endpoints, and exclude prerendered endpoints from the generated route manifests.

[benmccann]

Guess I should have read the comments before approving 😁

Are there any non-prerendered pages on the SvelteKit site? Maybe you could use adapter-static with the fallback option?

Or you might be able to do something like:

	if (process.env.NODE_ENV === 'production' && !$prerendering) {
		return { status: 404 };
	}

[Rich-Harris]

adapter-static is an option, but only because we happen not to have any dynamic pages yet — i'd rather fix the underlying issue. deploying a 'real' app also means we get custom error pages instead of the minimalist Vercel black-on-white status code

[Rich-Harris]

have gone with the temporary workaround since prerendered endpoints might be a bit of a rabbit hole (e.g. i think we would want to do #4112 first)

[Rich-Harris]

gah, still 500ing https://kit-svelte-dev-h9zzmhvx6-svelte.vercel.app/docs/foo

[Rich-Harris]

It should be loading /docs.json from prerendered files, but isn't 🤔

[Rich-Harris]

closing this in favour of #4093