nginx.conf

worker_processes  1;

events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/octet-stream;

    sendfile        on;
    #tcp_nopush     on;

    #keepalive_timeout  0;
    keepalive_timeout  65;

    #gzip  on;

    server {
        listen       443;
        server_name  IP/domain name;

        ssl on;
        ssl_certificate      C:/nginx-1.14.1/ssl/gor_proxy.crt;
        ssl_certificate_key  C:/nginx-1.14.1/ssl/gor_proxy.key.org;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

        location / {
            proxy_pass https://a.com;
	          post_action @afterdownload;
        }

	location @afterdownload {
    	    proxy_pass http://b.com$uri?$args;
	}

        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }

    }
}