Nginx + phpFPM: PATH_INFO always empty

Question

I configured nginx stable (1.4.4) + PHP (using FastCGI, php-fpm) on Debian. That works fine:

     location ~* ^/~(.+?)(/.*\.php)$ {
        fastcgi_split_path_info ^(.+?\.php)(/.*)$;
        alias /home/$1/public_html$2;
        fastcgi_pass unix:/var/run/php5-fpm.sock;
        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $request_filename;
        fastcgi_index index.php;
        autoindex on;
     }

I use the PATH_INFO variable, therefore I added the following line to fastcgi_params:

fastcgi_param   PATH_INFO       $fastcgi_path_info;

And in /etc/php5/fpm/php.ini:

cgi.fix_pathinfo = 0

I think that should work, but when I print out all server variables, PATH_INFO is always empty:

    array (
  'USER' => 'www-data',
  'HOME' => '/var/www',
  'FCGI_ROLE' => 'RESPONDER',
  'QUERY_STRING' => '',
  'REQUEST_METHOD' => 'GET',
  'CONTENT_TYPE' => '',
  'CONTENT_LENGTH' => '',
  'SCRIPT_FILENAME' => '/usr/share/nginx/html/srv_var.php',
  'SCRIPT_NAME' => '/srv_var.php',
  'PATH_INFO' => '',
  'REQUEST_URI' => '/srv_var.php',
  'DOCUMENT_URI' => '/srv_var.php',
  'DOCUMENT_ROOT' => '/usr/share/nginx/html',
  'SERVER_PROTOCOL' => 'HTTP/1.1',
  'GATEWAY_INTERFACE' => 'CGI/1.1',
  'SERVER_SOFTWARE' => 'nginx/1.4.4',
  .....
)

I can not figure where the problem is. Any ideas?

Answer 1

I stumbled across a solution to this. The $fastcgi_path_info var works together with $fastcgi_split_path_info, and needs to be set within the location block. Here's what worked in our environment:

location ~ [^/]\.php(/|$) {
    root /var/www/jurism-php;
    if (!-f $document_root$fastcgi_script_name) {
        return 404;
    }
    # Mitigate https://httpoxy.org/ vulnerabilities
    fastcgi_param HTTP_PROXY "";
    fastcgi_split_path_info ^(.+\.php)(/.+)$;
    include fastcgi_params;
    fastcgi_param PATH_INFO $fastcgi_path_info;
    fastcgi_pass unix:/var/run/php5-fpm.sock;
    fastcgi_index index.php;
}

There is also an example in the Nginx documentation under fastcgi_split_path_info.

(... which I now see matches more than one post above. Possibly the PATH_INFO line needs to be set after the include statement, to avoid clobbering the value.)