svelte/sites/svelte.dev/src/routes/tutorial/[slug]/+page.server.js

import {
	get_parsed_tutorial,
	get_tutorial_data,
	get_tutorial_list
} from '$lib/server/tutorial/index.js';
import { error, redirect } from '@sveltejs/kit';

export const prerender = true;

export async function load({ params }) {
	if (params.slug === 'local-transitions') redirect(307, '/tutorial/global-transitions');

	const tutorial_data = await get_tutorial_data();
	const tutorials_list = get_tutorial_list(tutorial_data);

	const tutorial = await get_parsed_tutorial(tutorial_data, params.slug);

	if (!tutorial) error(404);

	return {
		tutorials_list,
		tutorial,
		slug: params.slug
	};
}

export async function entries() {
	const tutorials_list = get_tutorial_list(await get_tutorial_data());
	const slugs = tutorials_list
		.map(({ tutorials }) => tutorials)
		.flatMap((val) => val.map(({ slug }) => ({ slug })));

	// to force redirect
	slugs.push({ slug: 'local-transitions' });

	return slugs;
}