CORS fetch-request with credentials

cors-fetch-express.md

This sounds easy but... it isn't!

Client side

Use this fetch options:

fetch('superUnsecureCorsUrl',{
   credentials: 'include'
})

Server side (express backend)

const cors = require('cors');
const app = express();

//Allow CORS requests
var corsOptions = {
    origin: 'trustedClientUrl',
    credentials: true 
    };
app.use(cors(corsOptions))

Note that origin property can not be '*'.