Anything wrong with using 599, 598 error codes for logic?

[brianmercer]

I'm new here, thanks.  I'm writing rules for Drupal using the Boost static caching module (like wp-super-cache).  Is there anything wrong with using fake error codes like 599, 598 and internal locations to control logic?


server {
	listen  80;
	server_name  example.com;
	access_log /var/log/nginx/example.com.access.log;
	error_log /var/log/nginx/example.com.error.log;
	root /var/example.com;
	index index.php;

	if ($host !~* ^(example.com)$ ) { # deny illegal host headers
		return 444;
	}

	location / {
		rewrite ^/(.*)/$ /$1 permanent; # remove trailing slashes for SEO
		error_page 404 @drupal; 

		try_files $uri @cache;
	}

	location @cache {
		if ( $request_method !~ GET ) { 
			return 599;
		}
		if ($http_cookie ~ "DRUPAL_UID") {
			return 599;
		}
		error_page 599 = @drupal;

		expires epoch;
		add_header Cache-Control "must-revalidate, post-check=0, pre-check=0";
		charset utf-8;

		try_files /cache/$host${uri}_$args.html @drupal;
	}

	location @drupal {
		rewrite ^/(.*)$ /index.php?q=$1 last;
	}

	location ~ \.php$ {
		try_files $uri @drupal; #check for existence of php file
		fastcgi_pass 127.0.0.1:9000;
		fastcgi_index index.php;
		fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
		include /etc/nginx/fastcgi_params;
	}

	location ~ \.css$ {
		if ( $request_method !~ GET ) {
			return 598;
		}
		if ($http_cookie ~ "DRUPAL_UID") {
			return 598;
		}
		error_page 598 = @x598;

		access_log      off;
		error_log /dev/null crit; # prevent debugging  if compiled --with-debug
		expires         max; #if using aggregator

		try_files /cache/$host${uri}_.css $uri @x404;
	}
	
	location ~ \.js$ {
		if ( $request_method !~ GET ) {
			return 598;
		}
		if ($http_cookie ~ "DRUPAL_UID") {
			return 598;
		}
    error_page 598 = @x598;

		access_log  off;
		expires  max; # if using aggregator

		try_files /cache/$host${uri}_.js $uri @x404;
	}

	location @x598 {
		access_log  off;
		expires  max; # max if using aggregator, otherwise sane expire time
	}

	location ~* ^.+\.(jpg|jpeg|gif|png|ico)$ {
		if ($http_referer !~ ^(http://example.com) ) { # prevent image hijacking
			return 444;
		}

		access_log      off;
		expires         45d;

		try_files $uri @x404;
	}

	location @x404 {
		return 404;
	}

	location ~ /\. {
		deny all;
	}

	location ~* ((cron\.php|settings\.php)|\.(htaccess|engine|inc|info|install|module|profile|pl|po|sh|.*sql|theme|tpl(\.php)?|xtmpl)$|^(Entries.*|Repository|Root|Tag|Template))$ {
		deny all;
	}
}


Posted at Nginx Forum: http://forum.nginx.org/read.php?2,3482,3482#msg-3482