FEATURE: Add a mail command (not only) for testing

This adds the command mail:send to send a mail
through swiftmailer.

Classes/Command/EmailCommandController.php

@@ -0,0 +1,45 @@
+<?php
+declare(strict_types=1);
+
+namespace Neos\SwiftMailer\Command;
+
+/*
+ * This file is part of the Neos.SwiftMailer package.
+ *
+ * (c) Contributors of the Neos Project - www.neos.io
+ *
+ * This package is Open Source Software. For the full copyright and license
+ * information, please view the LICENSE file which was distributed with this
+ * source code.
+ */
+
+use Neos\Flow\Cli\CommandController;
+use Neos\SwiftMailer\Message;
+
+class EmailCommandController extends CommandController
+{
+    /**
+     * A command for creating and sending simple emails.
+     *
+     * @param string $from The from address of the message
+     * @param string $to The to address of the message
+     * @param string $subject The subject of the message
+     * @param string $body The body of the message
+     * @param string $contentType The body content type of the message (Default: test/plain)
+     * @param string $charset The body charset of the message (Default: UTF8)
+     */
+    public function sendCommand(string $from, string $to, string $subject, string $body = '', string $contentType = 'text/plain', $charset = 'UTF8'): void
+    {
+        $message = (new Message())
+            ->setFrom($from)
+            ->setTo($to)
+            ->setSubject($subject)
+            ->setBody($body)
+            ->setContentType($contentType)
+            ->setCharset($charset);
+
+        $sentMessages = $message->send();
+
+        $this->outputLine(sprintf('<success>%s emails were successfully sent.</success>', $sentMessages));
+    }
+}