Reroute all emails to developer / debug address

Question

I am trying to intercept outgoing emails from joomla and reroute them to my email address for development and testing. Ideally I could set up a toggle under Global Configuration > Server > Email settings so that other non-developer teammates can control it easily as well, but the back end needs to be in place first.

If there is a plugin or built in that handles this kind of thing, that would be great but I can't find it.

I have read through and attempted the following (very old) solutions but I don't think it is going to work with 3.9. At least not without some tweaking:

• https://stackoverflow.com/questions/20965651/intercept-all-joomla-outgoing-emails-reroute-them-to-a-specified-address
• https://stackoverflow.com/questions/15546270/joomla-mail-goes-to-spam-folder-how-to-add-text-plain-when-sending-html-email
• https://gist.github.com/dongilbert/3237387

I found a newer override solution, but I'm not sure it will work with core joomla email functions:

• Override JHtml (HTMLHelper) class methods

Answer 1

You could use this extension: https://extensions.joomla.org/extension/jmail-queue/

And then simply view the emails in the queue. Or add the onInjection plugin to remove all the recipients and substitute the one you want.

Answer 2

I'm not sure how reliable this is but it can be done by setting Joomla\CMS\Factory::$mailer to an instance of your custom mailer. This should be done by a system plugin early in the request. The class should extend Joomla\CMS\Mail\Mail and the instance should already be configured to use settings from global configuration.

defined('_JEXEC') or exit;

use Joomla\CMS\Factory;
use Joomla\CMS\Plugin\CMSPlugin;

class PlgSystemCustommail extends CMSPlugin
{
    public function onAfterInitialise()
    {
        // This check isn't necessary but it ensures mail is sent using only one mailer, whichever it may be. Add custom logic as needed.
        if (Factory::$mailer === null)
        {
            // Set the mailer.
            Factory::$mailer = $this->createMailer();
        }
    }
    
    private function createMailer(): MyMail
    {
        // Load the custom class.
        JLoader::register('MyMail', __DIR__ . '/mymail.php');

        // Instantiate the custom mailer.
        $mailer = new MyMail;
        
        // Configure the mailer here. See `Joomla\CMS\Factory::createMailer()` for an example.
        
        // Return the mailer instance.
        return $mailer;
    }
}

Custom mailer class modified to send mail to specific address:

defined('_JEXEC') or exit;

use Joomla\CMS\Mail\Mail;

class MyMail extends Mail
{
    public function send()
    {
        // Clear recipient list.
        $this->clearAddresses();
        
        // Add custom recipient.
        $this->addRecipient($address, $name);
        
        return parent::send();
    }
}