Hooks (handle, handleError, handleFetch) in Svelte - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the handle hook in SvelteKit?

The handle hook lets you run code for every request before it reaches your routes. You can modify the request or response, add headers, or run authentication checks.

beginner

How does the handleError hook help in SvelteKit applications?

The handleError hook catches errors that happen during requests. It lets you log errors or show custom error messages to users in a friendly way.

intermediate

What is the role of the handleFetch hook in SvelteKit?

The handleFetch hook lets you intercept and modify fetch requests made during server-side rendering. You can add headers, change URLs, or mock responses.

beginner

Where do you define the handle, handleError, and handleFetch hooks in a SvelteKit project?

You define these hooks inside the src/hooks.server.js or src/hooks.server.ts file. This file runs on the server for all requests.

intermediate

Can the handleFetch hook modify fetch requests made from the client side in SvelteKit?

No, handleFetch only affects fetch requests made during server-side rendering or load functions on the server. Client-side fetches are not intercepted by this hook.

Which hook in SvelteKit runs before every request to modify the request or response?

A handle

B handleError

C handleFetch

D onMount

The handle hook runs before every request and can modify the request or response.

What is the main use of the handleError hook?

A To catch and handle errors during requests

B To run code after the response is sent

C To intercept fetch requests

D To modify client-side events

handleError is used to catch and handle errors during requests.

Where do you place the hooks like handle and handleFetch in a SvelteKit project?

A src/routes/hooks.js

B src/hooks.server.js

C src/lib/hooks.js

D static/hooks.js

Hooks are defined in src/hooks.server.js or src/hooks.server.ts.

Which hook allows you to modify fetch requests during server-side rendering?

A handleError

B handle

C onDestroy

D handleFetch

handleFetch lets you modify fetch requests during server-side rendering.

Can handleFetch modify fetch requests made from the browser after the page loads?

A Yes, always

B Only if enabled in config

C No, only server-side fetches

D Only for POST requests

handleFetch only affects fetches made on the server, not client-side fetches.

Explain how the handle hook works in SvelteKit and give an example of when you might use it.

Think about what you want to do before your app handles a user request.

Describe the difference between handleError and handleFetch hooks in SvelteKit.

One deals with problems, the other with data fetching.