Don't pull your dependencies 1

DependencyPuller.php

<?php
// src/frastel/BlogPlaygroundBundle/Container/DependencyPuller.php

namespace frastel\BlogPlaygroundBundle\Container;

use Symfony\Component\DependencyInjection\ContainerInterface;

class DependencyPuller
{
    private $container;

    public function __construct(ContainerInterface $container)
    {
        $this->container = $container;
    }

    public function doSomething()
    {
        $result = false;

        // do some fency stuff here
        $result = true;

        $this->container->get('logger')->debug('before sending mail');

        $message = \Swift_Message::newInstance()
            ->setSubject('Some subject')
            ->setTo('test@example.com')
            ->setBody('Some body');

        $this->container->get('mailer')->send($message);

        $this->container->get('logger')->debug('after sending mail');

        return $result;
    }
}