Step 1
Create a new php file in the override/controllers/front folder, and name it:
ContactController.php
Step 2
Insert this code inside the file:
class ContactController extends ContactControllerCore
{
public function postProcess()
{
if(Tools::isSubmit('submitMessage')) {
$message = Tools::getValue('message');
$from = Tools::getValue('from');
$banned_in_email = ['.ru', 'qq.com', '.vn']; // Make sure that you add your own extensions here
$banned_content = ['email marketing'];
foreach ($banned_in_email as $string) {
if(strstr($from, $string))
$this->errors[] = Tools::displayError('This email address is not allowed');
}
foreach ($banned_content as $string) {
if(strstr($message, $string))
$this->errors[] = Tools::displayError('Invalid Content');
}
}
parent::postProcess();
}
}
Step 3
Upload the file to the site with FTP and clear PrestaShop Cache. To do so go to admin panel -> Advanced Parameters -> Performance and click the clear cache button.
Step 4
Go to your shop contact form and try to send a message by using the form and a test email (eg. test@qq.com). Make sure that you cannot do so.
Learning Resources