CORS origin undefined with simple nodejs server - node.js

Question

I have a very simple nodejs server, but using the 'cors' package seems to not recognize the origin of the request for some reason.
Here is my nodejs server config:
const cors = require('cors');
const express = require('express');
const CORS_WHITELIST = [ 'http://localhost:5000' ];
const corsOptions = {
origin: (origin, callback) => {
console.log(origin) // ----> this is always 'undefined'
if (CORS_WHITELIST.indexOf(origin) !== -1){
callback(null, true)
} else {
callback(new Error('Not allowed by CORS'))
}
}
};
const configureServer = app => {
app.use(cors(corsOptions));
};
module.exports = configureServer;
Here is my server starter file:
const express = require('express');
const SERVER_CONFIGS = require('./constants/server');
const configureServer = require('./server');
const configureRoutes = require('./routes');
const app = express();
configureServer(app);
configureRoutes(app);
app.listen(SERVER_CONFIGS.PORT, error => {
if (error) throw error;
console.log('Server running on port: ' + SERVER_CONFIGS.PORT);
});
I am running this server on localhost, but the origin in the cors callback is always 'undefined'. For example when I open http://localhost:5000 on the browser or do a curl call.
How can I use cors so that it doesn't block the request on localhost?

Answer 1

I read this issue and req.headers.origin is undefined question and also CORS and Origin header!
source:
The origin may be hidden if the user comes from an ssl encrypted website.
Also: Some browser extensions remove origin and referer from the http-request headers, and therefore the origin property will be empty.
There is a solution to solve this by adding a middleware:
app.use(function (req, res, next) {
req.headers.origin = req.headers.origin || req.headers.host;
next();
});
I hope these helps. The issue is in awaiting more info state!