Dev server: Initial call to backend to get cookies

[ImpulseTheFox]

Clear and concise description of the problem

I'm missing cookies (for example JSESSIONID, X-XRSF-TOKEN) when I use the dev server (localhost:3000). This makes the first POST request fail since there is no xsrf-token. Having no session can also cause problems in application logic.

Suggested solution

Vite should, at the beginning of accessing the website, make a call to the backend server and proxy the cookies to the browser.
The backend server URL is specified by server.proxy.init.
Optional: Values in mappings can now be replaced with ^ to use the value of server.proxy.init.

vite.conf.js

{
	server: {
		proxy: {
			init: "http://localhost:8081",
			mappings: {
				"/api": "^"
			}
		}
	}
}

Alternative

Currently I am using this workaround:

I created a dummy GET endpoint that doesn't return anything, just to call it and get the cookies.

export default {
	name: "App",

	components: {
		//...
	},
	setup() {
		//...

		if (window.location.href === 'http://localhost:3000/') {
			axios.get("/api/xsrf")
		}

		return {
			//...
		}
	}
}

Additional context

No response

Validations

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• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[sapphi-red]

I think that workaround is the way to go. I guess you can also do it by adding a middleware that sends a request to the backend and sets Set-Cookie header. If you want the HTML to be served by servers other than Vite, we recommend using the backend integration feature.
https://vitejs.dev/guide/backend-integration.html