PHP / Symfony: create zip file mail attachments in memory

composer.json

{
    "type": "project",
    "license": "proprietary",
    "require": {
        "php": "^7.1.3",
        "ext-ctype": "*",
        "ext-iconv": "*",
        "badcow/lorem-ipsum": "^1.1",
        "maennchen/zipstream-php": "^0.5.2",
        "symfony/console": "*",
        "symfony/flex": "^1.1",
        "symfony/framework-bundle": "*",
        "symfony/swiftmailer-bundle": "^3.2",
        "symfony/yaml": "*"
    },
    "require-dev": {
        "symfony/dotenv": "*"
    },
    "config": {
        "preferred-install": {
            "*": "dist"
        },
        "sort-packages": true
    },
    "autoload": {
        "psr-4": {
            "App\\": "src/"
        }
    },
    "autoload-dev": {
        "psr-4": {
            "App\\Tests\\": "tests/"
        }
    },
    "replace": {
        "paragonie/random_compat": "2.*",
        "symfony/polyfill-ctype": "*",
        "symfony/polyfill-iconv": "*",
        "symfony/polyfill-php71": "*",
        "symfony/polyfill-php70": "*",
        "symfony/polyfill-php56": "*"
    },
    "scripts": {
        "auto-scripts": {
            "cache:clear": "symfony-cmd"
        },
        "post-install-cmd": [
            "@auto-scripts"
        ],
        "post-update-cmd": [
            "@auto-scripts"
        ]
    },
    "conflict": {
        "symfony/symfony": "*"
    },
    "extra": {
        "symfony": {
            "allow-contrib": false,
            "require": "4.1.*"
        }
    }
}

SendMailCommand.php

<?php

namespace App\Command;

use Badcow\LoremIpsum\Generator;
use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;
use ZipStream\ZipStream;

class SendMailCommand extends Command
{
    /**
     * @var \Swift_Mailer
     */
    private $mailer;

    public function __construct(\Swift_Mailer $mailer)
    {
        parent::__construct('mailer');
        $this->mailer = $mailer;
    }

    protected function configure()
    {
        $this
            // the name of the command (the part after "bin/console")
            ->setName('send:mail');
    }

    protected function execute(InputInterface $input, OutputInterface $output)
    {
        $memoryStream = fopen('php://memory', 'w+b');
        $arch = new ZipStream(null, [
            ZipStream::OPTION_OUTPUT_STREAM => $memoryStream
        ]);

        $arch->addFile("lorem-ipsum.txt", $this->getText());
        $arch->finish();

        rewind($memoryStream);
        $data = stream_get_contents($memoryStream);

        $attachment = new \Swift_Attachment($data, 'attachmemt.zip', 'application/zip');
        $message = (new \Swift_Message('Hello Email'))
            ->setFrom('from@example.com')
            ->setTo('address@example.com')
            ->setBody('Hello')
            ->attach($attachment);
        ;

        $this->mailer->send($message);
    }

    private function getText() {
        $lorem = new Generator();
        return implode("\n", $lorem->getParagraphs(100));
    }
}