How to get Email Queue ID with swiftmailer?

Question

When I send email using telnet smtp server answers me 250 2.0.0 Ok: queued as 7A821440123E when email was sent. So I need to get ID 7A821440123E to track email in mail log. Is it posible to get this with Swiftmailer?

Answer 1

SwiftMailer is event based so it can be easily extended by other developers. Every time the send method on Swift_Transport is called the proper event is dispatched. You can either use already developed listeners (plugins) or write your own which will be more customized.

Existing plugin

SwiftMailer comes out already with a few plugins that you can use to solve your problem.

Simply use the logger plugin. It will log all command calls within Swift_Transport implementation.

Example

$transport = Swift_SmtpTransport::newInstance('example.com', 25);

$mailer = Swift_Mailer::newInstance($transport);
$mailer->registerPlugin(
    new Swift_Plugins_LoggerPlugin(
        new Swift_Plugins_Loggers_EchoLogger(false)
    )
);

$message = Swift_Message::newInstance('Wonderful Subject');

$mailer->send($message);

Output

++ Starting Swift_SmtpTransport
<< 220 example.com ESMTP ready

>> EHLO [127.0.0.1]

<< 250-example.com
250-SIZE 5242880
250-PIPELINING
250-ENHANCEDSTATUSCODES
250-8BITMIME
250-DSN
250-AUTH PLAIN LOGIN CRAM-MD5
250 STARTTLS

>> AUTH CRAM-MD5

<< 235 2.0.0 OK

++ Swift_SmtpTransport started
>> MAIL FROM: <[email protected]>

<< 250 2.1.0 Ok

>> RCPT TO: <[email protected]>

<< 250 2.1.0 Ok

>> DATA

<< 354 Go ahead

>>
.

<< 250 2.0.0 Ok: queued as 7A821440123E

1++ Stopping Swift_SmtpTransport
>> QUIT

<< 221 2.0.0 Bye

++ Swift_SmtpTransport stopped

As you can see at the end, there is the desired id.

Custom plugin

Swift_Transport provides an interface for registering a plugin. It is nothing more than attaching an event listener to the event dispatcher. You can write a simple plugin by yourself. Everything you need to do is to implement the Swift_Events_ResponseListener

class FindEmailIdResponse implements Swift_Events_ResponseListener
{
    /**
     * {@inheritdoc}
     */
    public function responseReceived(Swift_Events_ResponseEvent $evt)
    {
        if (strpos($evt->getResponse(), 'queued') !== false) {
             // do whatever you want with the response or event
        }
    }
}

And then simply register your plugin in the mailer instance

$mailer->registerPlugin(new FindEmailIdResponse());