Possible bug w/ form actions?

[kyllerss]

I am a little stumped on this one. Perhaps someone here can help before I go through the process of creating a bug report. I have a form that was working fine a few days ago. I updated to the latest, and this form handler broke. I didn't make any code changes.

I have an action (/home/pets/upload/+page.server.ts):

import { type RequestEvent, redirect } from "@sveltejs/kit";
import type { Actions } from './$types';

/** @type {import('./restricted/upload').PageServerLoad} */
export async function load(event: RequestEvent) {

    // <some work here>
    return {a: true, b: 1};
}

export const actions: Actions = {
    default: async (event: RequestEvent) => {

        // <handle post data>

        throw redirect(302, "/home/pets/upload/finish");
    }
};

The form that performs the post looks like this (/home/pets/upload/+page.svelte):

        <form method="POST">
            <input ... />
            <input type="submit" value="Submit"/>
        </form>

When I attempt to perform a POST to it, I get a 404. The logs show the following:

docker-app-1     |  ›   Warning: Missing form submission function handler
docker-app-1     | Request from ::ffff:172.18.0.5: POST /home/pets/upload
docker-app-1     | Response with status 404 in 2 ms.
docker-app-1     |  ›   Warning: Missing form submission function handler
docker-app-1     | Request from ::ffff:172.18.0.5: POST /home/pets/upload.html
docker-app-1     | Response with status 404 in 0 ms.
docker-app-1     |  ›   Warning: Missing form submission function handler
docker-app-1     | Request from ::ffff:172.18.0.5: POST /home/pets/upload.htm
docker-app-1     | Response with status 404 in 0 ms.
docker-app-1     |  ›   Warning: Missing form submission function handler
docker-app-1     | Request from ::ffff:172.18.0.5: POST /home/pets/upload/index.html
docker-app-1     | Response with status 404 in 0 ms.
docker-app-1     |  ›   Warning: Missing form submission function handler
docker-app-1     | Request from ::ffff:172.18.0.5: POST /home/pets/upload/index.htm
docker-app-1     | Response with status 404 in 0 ms.

The network headers are (after some minor cleanup):

POST /home/pets/upload HTTP/1.1
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8
Accept-Encoding: gzip, deflate
Accept-Language: en-US,en;q=0.5
Cache-Control: no-cache
Connection: keep-alive
Content-Length: 70
Content-Type: application/x-www-form-urlencoded
Cookie: __cflb=XXXX; csrf_token_xxxx=xxxxxx=; xxxxxxxxxxxxx
Host: localhost:4173
Origin: http://localhost:4173
Pragma: no-cache
Referer: http://localhost:4173/home/pets/upload
Sec-GPC: 1
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36

HTTP/1.1 404 Not Found
Access-Control-Allow-Credentials: true
Access-Control-Allow-Origin: http://localhost:4173
Access-Control-Expose-Headers: Set-Cookie, Cache-Control, Expires, Last-Modified, Pragma, Content-Length, Content-Language, Content-Type
Date: Mon, 24 Oct 2022 22:16:19 GMT
Strict-Transport-Security: max-age=0;
Vary: Origin
X-Powered-By: Express
Content-Length: 21
Content-Type: text/plain; charset=utf-8

I am using SvelteKit (v1.0.0-next.524). This used to work as of a few days ago. I didn't see anything in the release notes that would indicate what changed. I'm assuming this is a bug, but I will hold back on filing one if anyone sees something that I am missing.

Thank you!

[kyllerss]

I have git-bisected the issue to upgrading sveltekit from 1.0.0-next.519 to 1.0.0-next.522. I'll look a little more closely to see if I can spot anything in the release notes that may help explain this or if it is a bug.

[kyllerss]

Filed a bug here.