Sveltejs Academy · Lesson

The handle() Hook: Middleware for Requests

Intercept every incoming request, modify event.locals, and call resolve().

Lesson 1 of 413 steps

The handle() Hook: Middleware for Requests is a free Sveltejs Academy lesson on CoddyKit. This is lesson 1 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Sveltejs Academy learning path, and your progress syncs across the web and the CoddyKit app. The Sveltejs Academy course includes 4 lessons in total.

Server Hooks

Hooks live in src/hooks.server.js. They run on every server request.

Export handle

Export an async function named handle that receives { event, resolve }.

export async function handle({ event, resolve }) {
  // do stuff before
  const res = await resolve(event);
  // do stuff after
  return res;
}

Modify Event

Set event.locals to expose data to load and endpoints.

event.locals.user = await getUser(event.cookies.get("sid"));

Inspect or Replace Response

After resolve(event), you can inspect or modify the response.

Logging Requests

A handle hook is a great place to add request logging or timing metrics.

Authentication Layer

Read cookies, fetch the user, attach to locals. Pages and APIs can then trust locals.

Composing Hooks

Multiple concerns can be wrapped in helpers and combined with sequence().

CORS Headers

Add CORS headers on the way out for APIs that serve other origins.

Performance

Hooks run on every request. Keep them fast and async-safe.

Skipping Static Assets

SvelteKit skips hooks for static files. Your hook only runs for app routes.

TypeScript

Use Handle type from @sveltejs/kit for typed implementations.

Quick Check

Where do server hooks live?

Recap

The handle hook in hooks.server.js intercepts every request. Populate locals for downstream code.

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Frequently Asked Questions

Is the “The handle() Hook: Middleware for Requests” lesson free?

Yes — the full text of “The handle() Hook: Middleware for Requests” is free to read here on the web. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Sveltejs Academy course, upgrade to CoddyKit PRO. The Sveltejs Academy course includes 4 lessons in total.

What will I learn in “The handle() Hook: Middleware for Requests”?

Intercept every incoming request, modify event.locals, and call resolve(). You practise Sveltejs Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.

Do I need any experience to start Sveltejs Academy?

No prior experience is required. Sveltejs Academy on CoddyKit is structured for beginners through advanced learners, so you can start here or from the beginning and move at your own pace. This is lesson 1 of 4.

How long does the “The handle() Hook: Middleware for Requests” lesson take?

Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.

Can I write and run code in this Sveltejs Academy lesson?

Yes. Every Sveltejs Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.

All lessons in this course

  1. The handle() Hook: Middleware for Requests
  2. handleError for Server Error Logging
  3. The init() Hook
  4. Sequence() for Composing Hooks
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