Symfony Mailer is a powerful and flexible email sending library for PHP applications. It provides a robust API for creating and sending emails, supporting various transport methods and integrating seamlessly with the Symfony framework while also being usable as a standalone component.

Pros

• Supports multiple transport methods (SMTP, sendmail, etc.) with easy configuration
• Provides a high-level API for creating complex email messages with attachments and HTML content
• Integrates well with other Symfony components and can be used independently
• Offers excellent performance and scalability for sending large volumes of emails

Cons

• Learning curve can be steep for developers new to Symfony ecosystem
• Configuration might be complex for advanced use cases
• Limited built-in templates compared to some other mailing libraries
• Requires additional setup for certain features like queue-based sending

Code Examples

1. Sending a simple email:

use Symfony\Component\Mailer\MailerInterface;
use Symfony\Component\Mime\Email;

public function sendEmail(MailerInterface $mailer)
{
    $email = (new Email())
        ->from('sender@example.com')
        ->to('recipient@example.com')
        ->subject('Hello from Symfony Mailer')
        ->text('This is a test email.');

    $mailer->send($email);
}

2. Sending an HTML email with attachment:

$email = (new Email())
    ->from('sender@example.com')
    ->to('recipient@example.com')
    ->subject('HTML Email with Attachment')
    ->html('<p>This is an <strong>HTML</strong> email.</p>')
    ->attachFromPath('/path/to/document.pdf');

$mailer->send($email);

3. Using a custom transport:

use Symfony\Component\Mailer\Transport\Smtp\EsmtpTransport;

$transport = new EsmtpTransport('smtp.example.com', 587);
$mailer = new Mailer($transport);

$email = (new Email())
    // ... configure email

$mailer->send($email);

Getting Started

1. Install Symfony Mailer via Composer:

   composer require symfony/mailer
   

2. Configure the mailer in your Symfony application's config/packages/mailer.yaml:

   framework:
       mailer:
           dsn: 'smtp://user:pass@smtp.example.com:25'
   

3. Use the mailer in your controller or service:

   use Symfony\Component\Mailer\MailerInterface;
   use Symfony\Component\Mime\Email;
   
   class EmailController
   {
       public function sendEmail(MailerInterface $mailer)
       {
           $email = (new Email())
               ->from('hello@example.com')
               ->to('you@example.com')
               ->subject('Time for Symfony Mailer!')
               ->text('Sending emails is fun again!');
   
           $mailer->send($email);
   
           // ...
       }
   }