Fix error: has been blocked by CORS policy

Error: Access to XMLHttpRequest at 'server_address' from origin 'base_url_client' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.
-- Code:
const express = require('express');
const cors = require('cors');

const app = express();
const corsOptions = {
origin: '*',
optionsSuccessStatus: 200 // For legacy browser support
}