One feature that is missing in WordPress is a decent way to filter out comments by IP Address. I decided to tackle that today. First I will do it via a quick hack and then expand it to more tightly integrate with the backend. If someone would like to figure out how to make it a plugin, that would be awesome.

1. First you need to add a table to the WordPress database. I named mine wp_banned and added a simple column: IpAddress.
2. Open up /wp-includes/comment.php and look around line 676 for the wp_new_comment function. Add the following to the beginning:

   global $wpdb;
   
   $testIp = preg_replace( '/[^0-9a-fA-F:., ]/', '',$_SERVER['REMOTE_ADDR'] );
   
   $ipResults = $wpdb->get_results("SELECT * FROM wp_banned WHERE IpAddress = '".$testIp."'");
   if(count($ipResults) > 0)
   	return -1;

3. Upload, add ips to the database and then watch them not appear anymore.

Now I just need to figure out how to add some nice buttons to the comment page to “Ban and Spam” comments…