Sync kit docs (#1202)

sync kit docs

Co-authored-by: svelte-docs-bot[bot] <196124396+svelte-docs-bot[bot]@users.noreply.github.com>
Co-authored-by: Rich Harris <[email protected]>

Author: 3 people

apps/svelte.dev/content/docs/kit/20-core-concepts/20-load.md

@@ -714,6 +714,74 @@ To prevent data waterfalls and preserve layout `load` caches:
 
 Putting an auth guard in `+layout.server.js` requires all child pages to call `await parent()` before protected code. Unless every child page depends on returned data from `await parent()`, the other options will be more performant.
 
+## Using `getRequestEvent`
+
+When running server `load` functions, the `event` object passed to the function as an argument can also be retrieved with [`getRequestEvent`]($app-server#getRequestEvent). This allows shared logic (such as authentication guards) to access information about the current request without it needing to be passed around.
+
+For example, you might have a function that requires users to be logged in, and redirects them to `/login` if not:
+
+```js
+/// file: src/lib/server/auth.js
+// @filename: ambient.d.ts
+interface User {
+	name: string;
+}
+
+declare namespace App {
+	interface Locals {
+		user?: User;
+	}
+}
+
+// @filename: index.ts
+// ---cut---
+import { redirect } from '@sveltejs/kit';
+import { getRequestEvent } from '$app/server';
+
+export function requireLogin() {
+	const { locals, url } = getRequestEvent();
+
+	// assume `locals.user` is populated in `handle`
+	if (!locals.user) {
+		const redirectTo = url.pathname + url.search;
+		const params = new URLSearchParams({ redirectTo });
+
+		redirect(307, `/login?${params}`);
+	}
+
+	return locals.user;
+}
+```
+
+Now, you can call `requireLogin` in any `load` function (or [form action](form-actions), for example) to guarantee that the user is logged in:
+
+```js
+/// file: +page.server.js
+// @filename: ambient.d.ts
+
+declare module '$lib/server/auth' {
+	interface User {
+		name: string;
+	}
+
+	export function requireLogin(): User;
+}
+
+// @filename: index.ts
+// ---cut---
+import { requireLogin } from '$lib/server/auth';
+
+export function load() {
+	const user = requireLogin();
+
+	// `user` is guaranteed to be a user object here, because otherwise
+	// `requireLogin` would throw a redirect and we wouldn't get here
+	return {
+		message: `hello ${user.name}!`
+	};
+}
+```
+
 ## Further reading
 
 - [Tutorial: Loading data](/tutorial/kit/page-data)

apps/svelte.dev/content/docs/kit/98-reference/20-$app-server.md

@@ -7,9 +7,34 @@ title: $app/server
 
 ```js
 // @noErrors
-import { read } from '$app/server';
+import { getRequestEvent, read } from '$app/server';
+```
+
+## getRequestEvent
+
+<blockquote class="since note">
+
+Available since 2.20.0
+
+</blockquote>
+
+Returns the current `RequestEvent`. Can be used inside `handle`, `load` and actions (and functions called by them).
+
+In environments without [`AsyncLocalStorage`](https://nodejs.org/api/async_context.html#class-asynclocalstorage), this must be called synchronously (i.e. not after an `await`).
+
+<div class="ts-block">
+
+```dts
+function getRequestEvent(): RequestEvent<
+	Partial<Record<string, string>>,
+	string | null
+>;
 ```
 
+</div>
+
+
+
 ## read
 
 <blockquote class="since note">