Need help on nginx conf to work with ubercart file download

@brianmercer

We use nginx as reverse proxy before apache, to have the separation of static and dynamic content. Nginx takes care of most static files and apache processes php.

I temporarily solved the problem by using the rewrite directive in that location.

  location ~ ^/download/.*$  {
      # the rewrite works!
      rewrite ^ http://shop.2u4u.com.cn:7788$request_uri?;
      # the proxy_pass way doesn't work
      #proxy_pass http://apache; # or whatever you need to get to apache with the port specified
      #proxy_set_header  X-Real-IP  $remote_addr;
      #proxy_set_header Host $http_host;
      }

With this location directive, users access the site through port 80, and won't notice the download is at port 7788 unless they look at the header.

I don't understand 1. why proxy_pass doesn't work. 2. Is there someone running ubercart on a nginx/php-fcgi env? Do you have this problem? By reading the uc_file module source code, I don't think the ubercart code is strictly tighten to apache. Then why the proxy_pass doesn't work?

Maybe, just maybe apache doesn't get the user ip correctly?

Here is the relevant code in uc_file.page.inc

   * @param $file_user
   *   The file_user object from the uc_file_users
   * @param $ip
   *   The string containing the ip address the download is going to
   */
  function _uc_file_download_transfer($file_user, $ip) {

    // Check if any hook_file_transfer_alter calls alter the download.
    foreach (module_implements('file_transfer_alter') as $module) {
      $name = $module .'_file_transfer_alter';
      $file_user->full_path = $name($file_user, $ip, $file_user->fid, $file_user->full_path
  );
    }

  [snip]

  $ip = ip_address();
    $file_download = uc_file_get_by_key($key);

    $file_download->full_path = uc_file_qualify_file($file_download->filename);

    // If it's ok, we push the file to the user.
    $status = _uc_file_download_validate($file_download, $user, $ip);
    if ($status == UC_FILE_ERROR_OK) {
      _uc_file_download_transfer($file_download, $ip);
    }

Here is what my guess is based on:

X-Forwared-For is header where proxy servers usually add client addresses:
"192.168.1.1, 10.10.10.1, 10.10.1.1". The variable $proxy_add_x_forwarded_for
does this addition. X-Real-IP is non standard header, where nginx
sets client addresses. Usually you need just one of the them

$remote_addr and $http_remote_addr are different things:
$remote_addr is variable which value is a client's address taken
from socket options, while $http_remote_addr is variable which value
is client's HTTP request header "Remote-Addr" as any "$http_..."
variable: $http_user_agent, etc.

Usually underscores are not used in header name, therefore by default
nginx ignores headers with underscores in names.

I added the directive ( proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; ).

Still, it didn't work.

Since you tested on nginx+php-fpm and that worked, I am thinking the problem is on my part, probably some apache configuration (which is a standard conf comes with apache, only a few timeout/server pool tweaking, and disable keepalive since apache is at the backend).

I will use the rewrite way for the moment.

I can't run php-fpm for the moment because some issues with php-soap. I found some other obscure issues with nginx+apache (like global redirect module).

Some issues disappeared when run with php-fpm (thank you very much for that!), it makes me think it's because the environment of my set up not some faults in the nginx conf.

I thought by using nginx as reverse proxy with apache (separation of static and dynamic content) was the easier to implement and would attract more people to try out nginx with drupal. I guess I was wrong. Because, it seems to me most people in this group run nginx+php-fpm directly and there weren't many issues related to apache except from me. Either they all worked out smoothly or nobody is using it?