discriminate in hooks.server if request is from form action vs page first load?

[geko1971]

I'm wondering if there is a way to discriminate in the server hooks whether an incoming request was issued by an action-triggered page refresh vs a page initial load.

Reason is that I run an handle in server hooks that need to validate a certain authorization cookie expiration only when pages first load, but skip that validation for all subsequent refreshes of same page, when those are triggered for instance by form submissions.

It would be great if there could be (in the $app/navigation module? In the event itself?) a property declaring whether the event is related to page first load or a subsequent reload.

[david-plugge]

There´s a header called x-sveltekit-action that is set to true when calling with fetch from the client using use:enhance

kit/packages/kit/src/runtime/app/forms.js

Line 99 in f953c9d

'x-sveltekit-action': 'true'

[geko1971]

Thank you David. I am using form actions as exported by +page.server (not use:enhance action), since I need to perform server-side validation/augmentation of POSTed data: unfortunately, x-sveltekit-action http header seem not to be included with the requests in the case.

[eltigerchino]

This solution checks for the content-type header.
It can detect the request is a form action if it contains application/x-www-form-urlencoded.
https://stackblitz.com/edit/sveltejs-kit-template-default-35sq7b?file=src/hooks.server.js

Although, the code in hooks runs on every request, so you'd still have the issue of validation running on each page load. I suggest validating the cookie expiration in a +layout.server.js file so it runs only when the layout first mounts.

[eltigerchino]

@s3812497 is there a way to NOT invalidateAll for a POST action?

Yes, if you provide a custom callback to the enhance action

<form
  method="POST"
  use:enhance={({ form, data, action, cancel }) => {
    // `form` is the `<form>` element
    // `data` is its `FormData` object
    // `action` is the URL to which the form is posted
    // `cancel()` will prevent the submission

    return async ({ result }) => {
     // choose what you want to do when result === 'success'
     // this is where it usually invalidates all
    };
  }}
>

https://kit.svelte.dev/docs/form-actions#progressive-enhancement-use-enhance

or implement your own submit event listener https://kit.svelte.dev/docs/form-actions#progressive-enhancement-custom-event-listener.

[stefandevo]

Ok, but I want to redirect to another page after my Post. In this case it seems there is no way to not invalidateAll(). If I stay on the same page after posting, indeed, I can ignore the invalidateAll() call - but a redirect seems to invalidateAll() nevertheless.

[eltigerchino]

Do you mind sharing an example of how you have the form and action set up?

[stefandevo]

I created a small app here:
https://stackblitz.com/edit/sveltejs-kit-template-default-ecme4h?file=README.md

[eltigerchino]

Posted a working example on your other post. Hope it helps! :)
#9467 (comment)