Describe the bug

When the server shuts down, the client starts sending periodic ping requests to check if the server is back up and then reload. These requests reach the middlewares defined by the users but it should probably be handled by vite before it reaches any of these like the initial websocket upgrade request does. There is also no reliable way to identify these requests for the middlewares to ignore it themselves.

ref: sveltejs/kit#6910
ref: sveltejs/kit#7218

I could submit a PR, but can't tell which file would be responsible for intercepting it, is it ws.ts?

Reproduction

https://github.com/gtm-nayan/vite-ping-repro

Steps to reproduce

1. Run pnpm install

2. Run pnpm dev

3. Open the page

4. Turn off dev server

5. Restart the dev server (ideally set a breakpoint on this line to avoid the clutter from unrelated requests)

6. Observe that the custom middleware from vite.config.js will have first logged the request URL from the ping request

System Info

npmPackages:
    vite: ^4.3.5 => 4.3.5

Used Package Manager

pnpm

Logs

No response

Validations

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• The provided reproduction is a minimal reproducible example of the bug.