Vite Server Cors Allow Any Subdomain

vite.config.js

import { defineConfig, loadEnv } from 'vite';

// ...

export default defineConfig(({ mode }) => {
    const env = loadEnv(mode, process.cwd());

    const { protocol, hostname } = new URL(env.VITE_URL);

    const root = hostname.split('.').slice(-2).join('\\.');

    return {
        // ...
        server: {
            cors: {
                origin: new RegExp([
                    '^',               // Start of string
                    `${protocol}//`,   // Protocol and double slashes
                    '(?:[\\w-]+\\.)*', // Optional subdomains
                    `${root}`,         // Root domain (e.g., example.com)
                    '(?::\\d+)?',      // Optional port
                    '$',               // End of string
                ].join(''), 'i'),
            },
        },
    };
});