Symfony2 command to test rackspace authentication

RackspaceAuthenticationCommand.php

<?php

namespace Sbaam\Bundle\UtilsBundle\Command;

use Symfony\Component\Console\Command\Command,
    Symfony\Component\Console\Input\InputArgument,
    Symfony\Component\Console\Input\InputInterface,
    Symfony\Component\Console\Input\InputOption,
    Symfony\Component\Console\Output\OutputInterface;

class RackspaceAuthenticationCommand extends Command
{

    protected function configure()
    {
        $this
            ->setName('rackspace:authentication:test')
            ->setDescription('Performs authentication on rackspace multiple times and outputs the percentage of successful authentication')
            ->addOption( 'times', 't', InputOption::VALUE_OPTIONAL, 'The number of times authentication will be tried', 1 )
            ->addOption( 'delay', 'D', InputOption::VALUE_OPTIONAL, 'The number of seconds between each attempt')
            ->addOption( 'full', 'F', InputOption::VALUE_NONE, 'If true will enable the rackspace debug mode and prints out the whole requests headers')
        ;
    }

    protected function execute(InputInterface $input, OutputInterface $output)
    {
        /**
         * @var \Symfony\Component\DependencyInjection\ContainerInterface $container
         */
        $container = $this->getApplication()->getKernel()->getContainer();

        $username = $container->getParameter('rackspace_username');
        $apiKey = $container->getParameter('rackspace_apikey');

        $times = $input->getOption('times');
        $delay = $input->getOption('delay');
        $full = $input->getOption('full');

        $errors = array();
        $failures = 0;
        for($i=0; $i<$times; $i++)
        {
            $authentication = new \CF_Authentication($username, $apiKey);
            if($full)
                $authentication->setDebug(true);

            try
            {
                if($full)
                    $output->writeln(sprintf("\n<info>- Attempt #%d:</info>", $i));
                $authentication->authenticate();

                if(!$full)
                    $output->write('<info>.</info>');
            }
            catch (\Exception $e)
            {
                $errors[] = sprintf('[%s] %s ("%s" on line %d)'."\n%s", get_class($e), $e->getMessage(), $e->getFile(), $e->getLine(), $e->getTraceAsString());
                $failures++;

                if($full)
                    $output->writeln(sprintf('<error>%s</error>', $e->getTraceAsString()));
                else
                    $output->write('<error>.</error>');
            }

            if($delay && $delay > 0)
                sleep($delay);
        }

        $successRate = ($times - $failures) * 100 / $times;

        $output->write("\n\n<info>Success Rate: </info>");

        if($failures > 0)
            $output->writeln(sprintf('<error>%s%%</error>', $successRate));
        else
            $output->writeln(sprintf('<info>%s%%</info>', $successRate));

        if(!empty($errors))
            $output->writeln(sprintf("\n<error>%d</error> errors:", $failures));
        foreach($errors as $error)
        {
            $output->writeln(sprintf('<error>%s</error>', $error));
        }
    }

}