Expo-Cli tunnel problem accessing with a different hostname (401 unauthorized)

[fritzZz]

I'm using the command : expo start --tunnel to expose the web page to scan the QRCODE behind nginx.

Everything is working fine in localhost:19002, but behind NGINX using a different hostname (expo.mycompany.com) the ws connection (ws://expo.mycompany.com:19002/20ldcw_MHt3hl6t_ahe74XzAc1W5G7u40OpSN_Bi0qE/graphql) returns a 401 Unauthorized

I tried also putting in my /etc/hosts
127.0.0.1 myfakehost

and using myfakehost:19002 instead of localhost:19002 in local I get the same error 401.
that is something related to the exposure of the service on the tunnel with a different hostname.

To get a black page with the 401 error I used this approach :

Environment

ENV EXPO_DEVTOOLS_LISTEN_ADDRESS=0.0.0.0
ENV REACT_NATIVE_PACKAGER_HOSTNAME=expo.mycompany.com

expo diagnostics

Expo CLI 3.11.7 environment info:
System:
OS: Linux 4.14 Debian GNU/Linux 9 (stretch) 9 (stretch)
Shell: 4.4.12 - /bin/bash
Binaries:
Node: 10.18.1 - /usr/local/bin/node
Yarn: 1.21.1 - /usr/local/bin/yarn
npm: 6.13.4 - /usr/local/bin/npm
npmGlobalPackages:
expo-cli: 3.11.7

nginx version
nginx version: nginx/1.17.8

nginx.conf

map $http_upgrade $connection_upgrade{
        default upgrade;
        `` close;
}

upstream ws-expo {
        # enable sticky session based on IP
        #ip_hash;

        server expo-service:19002;
}

server {
    server_name expo.mycompany.com;
    listen 80;
    listen [::]:80;

    location / {
        proxy_pass http://expo-service:19002;
    }

}

server {
    server_name expo.mycompany.com;
    listen 19002;
    #listen [::]:19002;

    location / {
            #proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            #proxy_set_header Host $host;
            
            proxy_pass http://ws-expo;

            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
    }


}

[fritzZz]

Found a solution :

adding changing into the nginx.conf :

proxy_set_header Origin http://expo.mycompany.com:19002;

I found the right behavior into the dev-tools server

https://github.com/expo/expo-cli/blob/master/packages/dev-tools/server/DevToolsServer.js

And it considers also the port as part of the Host header to validate the client.