Getting correct SERVER_PORT to php-fpm through nginx and varnish

Question

The goal is to get PHP aware of the correct web-facing server_port.

The setup is:

nginx on port 443 reverse proxying to varnish on port 80 reverse proxying to nginx on port 8008 and running php-fpm as a fastcgi.

hitting 80 or 443 both work fine except that $_SERVER['SERVER_PORT'] in php is always showing 8008 by default. I can hard code a fastcgi_param server_port but then it will only be correct for 80 or 443 but not both.

# default
fastcgi_param  SERVER_PORT        $server_port;
# harcode to 80
fastcgi_param  SERVER_PORT        80;

How can I get the proper external-facing server port available to php?

Answer 1

Found my own answer

In the SSL nginx, this...

   proxy_set_header X-Forwarded-Proto https;

then in varnish, this...

 sub vcl_recv {
   if (req.http.X-Forwarded-Proto == "https" ) {
     set req.http.X-Forwarded-Port = "443";
   } else {
     set req.http.X-Forwarded-Port = "80";
     set req.http.X-Forwarded-Proto = "http";
   }
 }

then in the final nginx, this...

fastcgi_param  SERVER_PORT        $http_x_forwarded_port;