net::ERR_CONNECTION_REFUSED . How to correctly configure Nginx with Socket.io?

Sat Feb 1 09:45:00 UTC 2020

This is the "view source" of the html page:

    <!DOCTYPE html>
    <html lang="en">
      <head>
        <meta charset="utf-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <meta name="viewport"
content="width=device-width,initial-scale=1.0">
        <link rel="icon" href="favicon.ico">
        <title>testproject</title>
      <link href="js/app.js" rel="preload" as="script"><link
href="js/chunk-vendors.js" rel="preload" as="script"></head>
      <body>
        <noscript>
          <strong>We're sorry but testproject doesn't work properly without
JavaScript enabled. Please enable it to continue.</strong>
        </noscript>
        <div id="app"></div>
        <!-- built files will be auto injected -->
      <script type="text/javascript"
src="js/chunk-vendors.js"></script><script type="text/javascript"
src="js/app.js">  
    </script></body>
    </html>

This is the result of the "localhost" word search in app.js:

https://drive.google.com/open?id=11QpJKjd4PLKNMnO7m2utCJ9PrzO8Oyji  :

    /***/ }),

    /***/ 1:
/*!********************************************************************************************************************************************************************!*\
      !*** multi (webpack)-dev-server/client?http://localhost
(webpack)/hot/dev-server.js
(webpack)-dev-server/client?http://192.168.1.7:8080/sockjs-node
./src/main.js ***!

\********************************************************************************************************************************************************************/
    /*! no static exports found */
    /***/ (function(module, exports, __webpack_require__) {

    __webpack_require__(/*!
/home/marco/vueMatters/testproject/node_modules/webpack-dev-server/client  

    /index.js?http://localhost
*/"./node_modules/webpack-dev-server/client/index.js?http://localhost");
    __webpack_require__(/*!
/home/marco/vueMatters/testproject/node_modules/webpack/hot/dev-server.js  
    */"./node_modules/webpack/hot/dev-server.js");
    __webpack_require__(/*!
/home/marco/vueMatters/testproject/node_modules/webpack-dev-server/client 
    /index.js?http://192.168.1.7:8080/sockjs-node
*/"./node_modules/webpack-dev-server/client/index.js?http:  
    //192.168.1.7:8080/sockjs-node");
    module.exports = __webpack_require__(/*! ./src/main.js
*/"./src/main.js");

    /***/ })

    /******/ });

These are the results of the "localhost" word search in chunk-vendors.js : 

- https://drive.google.com/open?id=13EPYKgb7Vv4DHOTxD0jxYk_CbDDrJkMy
- https://drive.google.com/open?id=1UjWDsPyT-87GF4WJhVr-UhzOFGiBW8tH
- https://drive.google.com/open?id=1eq5pWm51sjCYQkIaQn5GZ6uEmrmS36Od
- https://drive.google.com/open?id=19QzxljB37HH5cvJ0jffdyX97u9hlBDsV

In this GitHub repository you can find all the related files:
https://github.com/marcoippolito/testproject

the sudo nano /etc/nginx/conf.d/default.conf is the following: 

    server {
        listen 443 ssl http2 default_server;
        server_name ggc.world;

        ssl_certificate /etc/ssl/certs/chained.pem;
        ssl_certificate_key /etc/ssl/private/domain.key;
        ssl_session_timeout 5m;
        ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;
        ssl_ciphers EECDH+CHACHA20:EECDH+CHACHA20-    

draft:EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DES:!MD5;
        ssl_prefer_server_ciphers on;
        ssl_session_cache shared:SSL:50m;
        ssl_dhparam /etc/ssl/certs/dhparam.pem;
        #ssl_stapling on;
        #ssl_stapling_verify on;

        access_log /var/log/nginx/ggcworld-access.log combined;

        add_header Strict-Transport-Security "max-age=31536000";
        location = /favicon.ico { access_log off; log_not_found off; }
        location / {
            proxy_pass http://127.0.0.1:8080;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
        }
    }

    server {
        listen 80 default_server;
        listen [::]:80 default_server;
        error_page 497 https://$host:$server_port$request_uri;
        server_name www.ggc.world;
        return 301 https://$server_name$request_uri;

        access_log /var/log/nginx/ggcworld-access.log combined;

        add_header Strict-Transport-Security "max-age=31536000";
        location = /favicon.ico { access_log off; log_not_found off; }
        location / {
            proxy_pass http://127.0.0.1:8080;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
        }
    }

    # https://www.nginx.com/blog/nginx-nodejs-websockets-socketio/
    # https://gist.github.com/uorat/10b15a32f3ffa3f240662b9b0fefe706 
    # http://nginx.org/en/docs/stream/ngx_stream_core_module.html

    upstream websocket {
        ip_hash;
        server localhost:3000;
    }

    server {
        listen       81;
        server_name  ggc.world www.ggc.world;

        #location / {
        location ~ ^/(websocket|websocket\/socket-io) {
            proxy_pass http://127.0.0.1:4201;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            proxy_set_header X-Forwared-For $remote_addr;
            proxy_set_header Host $host;

            proxy_redirect off;
            proxy_set_header X-Real-IP $remote_addr;
        }

    }
    #
https://stackoverflow.com/questions/40516288/webpack-dev-server-with-nginx-proxy-pass

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,286850,286887#msg-286887