Spam-proof Contact Form with PHP/Akismet
Sunday, May 9th, 2010 by Phillip NapieralskiThis is in addition to my previous post about creating a simple contact form. This post will utilize the Akismet service to classify some messages as spam.
The Prerequisites
To follow this tutorial, I assume you already have a simple contact form in place.
Akismet PHP Library
The folks at Aching Brain created a nifty PHP class to make utilizing the Akismet service easier. Download this library then put it in the same directory as your contact form file (Download mirror: AkismetPHPClass).
There are implementations available in other languages as well.
The PHP
This code will completely replace the PHP code from the previous post. However, I assume the HTML used is unchanged.
First, include the Akismet library:
<?php require "Akismet.class.php";
Now, create a more generic function for sending an email:
function send_mail( $name, $email, $website, $ip, $is_spam, $message)
{
$subject = '';
if( $spam == true )
$subject = "[SPAM?]";
$subject .= "[Your_site.com] E-mail received from ".$author_name."//".$author_email."//".$ip;
mail( "send_to_this_address@to.com", $subject,
$author_name.", ".$author_email.", ".$author_website. ".\r\n\r\n".$message);
}
If the $is_spam parameter is set to true, we simply prepend “[SPAM?]” at the beginning of the subject line. This allows us to see right away what it is in our inbox. Further, you could create an e-mail filter to automatically put these messages in a different e-mail folder.
Now, we have to set-up the Akismet class. This will require a WordPress API Key. If you don’t have one, it’s easy and free to get one.
if(isset($_POST['action']))
{
$wp_key = 'xXxXxXxXxXxX';
$our_url = 'http://www.your_website.com';
$name = $_POST['name'];
$email = $_POST['email'];
$website = $_POST['website'];
$message = $_POST['message'];
$ip = $_SERVER['REMOTE_ADDR'];
$akismet = new Akismet($our_url, $wp_key);
$akismet->setCommentAuthor($name);
$akismet->setCommentAuthorEmail($email);
$akismet->setCommentAuthorURL($website);
$akismet->setCommentContent($message);
$akismet->setUserIP($ip);
send_mail( $name, $email, $website, $ip, $akismet->isCommentSpam(), $message);
}
?>
That’s it! Now if a line of spammers hits your contact form, you have a safe guard against it. If you have questions about this piece of code or anything else, feel free to leave a comment!
In conlusion, Akismet is the best!
