upstream my-domain {
        server 127.0.0.1:8080; // nodejs and socketio running on same port. chnage or create new upstream for socket if socket running on different port
}

server {
        listen          80;
        server_name     *.example.com; //change domain
        return 301 https://$host$request_uri;
}

server {
        listen 443 ssl;
        server_name *.example.com;
        ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem; //handle by let's encrypt
        ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;//handle by let's encrypt
        include /etc/letsencrypt/options-ssl-nginx.conf;//handle by let's encrypt
        ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;//handle by let's encrypt

        location / {
                proxy_pass              http://my-domain;
                proxy_next_upstream     error timeout invalid_header http_500 http_502 http_503 http_504;
                proxy_redirect          off;
                proxy_buffering         off;

                proxy_set_header        Host                    $host;
                proxy_set_header        X-Real-IP               $remote_addr;
                proxy_set_header        X-Forwarded-For         $proxy_add_x_forwarded_for;
                proxy_set_header        X-Forwarded-Proto       $scheme;
                add_header              Front-End-Https         on;
        }

        location /socket.io/ {
                proxy_pass              http://my-domain;
                proxy_redirect          off;

                proxy_http_version      1.1;

                proxy_set_header        Upgrade                 $http_upgrade;
                proxy_set_header        Connection              "upgrade";
                proxy_set_header        Host                    $host;
                proxy_set_header        X-Real-IP               $remote_addr;
                proxy_set_header        X-Forwarded-For         $proxy_add_x_forwarded_for;
        }
}