http-proxy

location ~ "\/(?<ip>[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3})/(?<gohost>[^\/]*)(?<path>.*)" {

        # kill cache
        add_header Last-Modified $date_gmt;
        add_header Cache-Control 'no-store, no-cache, must-revalidate, proxy-revalidate, max-age=0';
        if_modified_since off;
        expires off;
        etag off;

	proxy_pass http://$ip/$path;
	proxy_set_header Host $gohost;
	proxy_set_header X-Forwarded-For $remote_addr;
	proxy_set_header Accept-Encoding ""; # no compression, otherwise sub_filters don't work

	# straight links for this site	
	sub_filter 'http://$gohost/' 'http://$baseline/$ip/$gohost/';
	sub_filter 'https://$gohost/' 'https://$baseline/$ip/$gohost/';

	# hrefs	
	sub_filter 'href="//' 'href="//'; #prevent // from being zapped
	sub_filter 'href="/' 'href="http://$baseline/$ip/$gohost/';
	
	# for subdomain switches, but breaks a lot of things
	#sub_filter 'href="http://' 'href="http://$baseline/$ip/';
	#sub_filter 'href="https://' 'href="https://$baseline/$ip/';

	# srcs	
	sub_filter 'src="/' 'src="http://$baseline/$ip/$gohost/';
	
	# for subdomain switches, but breaks a lot of things
	#sub_filter 'src="http://' 'src="http://$baseline/$ip/';
	#sub_filter 'src="https://' 'src="https://$baseline/$ip/';

	sub_filter_once off;
	sub_filter_types *;

	# redirects
	proxy_redirect http://$gohost http://$baseline/$ip/$gohost;
	proxy_redirect https://$gohost https://$baseline/$ip/$gohost;
	
	# cookies
	proxy_cookie_domain $gohost $baseline;
	proxy_cookie_path / /$ip/$gohost/;
	
	#proxy_http_version 1.1; # can't do this, breaks sub_filter...

}