HEAD requests with PHP-FPM

[F21]

I would like to be able to support HEAD requests. For the most part, HEAD
works well with static files. However, if I am trying to use a HEAD request
against a PHP file, it is missing the Content-Length or the
Transfer-Encoding header.

PHP-FPM is connected to nginx 1.2.8 using FCGI. I also have gzip enabled.

user  www-user;
worker_processes  1;

error_log  logs/error.log  info;

events {
    worker_connections  1024;
}

http {
    include mime.types;
    
    default_type  application/octet-stream;
    client_max_body_size 10M;

    sendfile        on;
    keepalive_timeout  65;


    gzip  on;
    gzip_types text/plain text/css application/json application/javascript
application/x-javascript text/javascript;

    server {
       server_name test.com;
       root   /web;

       location ~ \.php$ {
	fastcgi_intercept_errors on;
	fastcgi_pass   unix:/run/php/php-fpm.sock;
	fastcgi_index index.php;
	fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
	include        fastcgi_params;

       }

       listen       80  default_server;

       error_page   500 502 503 504  /50x.html;

    }
}


If I use a GET, everything works as expected:

$ curl -XGET http://test.com/phpinfo.php -I
HTTP/1.1 200 OK
Date: Tue, 09 Apr 2013 06:58:50 GMT
Content-Type: text/html
Transfer-Encoding: chunked <-------------------
Connection: keep-alive

But, if I use a HEAD, Transfer-Encoding is missing:

$ curl -XHEAD http://test.com/phpinfo.php -I
HTTP/1.1 200 OK
Date: Tue, 09 Apr 2013 06:59:24 GMT
Content-Type: text/html
Connection: keep-alive

What's the reason for nginx not including the Transfer-Encoding header? Is
there anyway to turn it on? Interestingly, if I try and set the
Transfer-Encoding header inside the PHP script, it is still removed by
nginx.

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,238218,238218#msg-238218