GraphQL-202: [Mutations] moves validation logic to separate module

Author: Tobias Maile

app/code/Magento/SendFriendGraphQl/Model/Validation/Validation.php

@@ -0,0 +1,69 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\SendFriendGraphQl\Model\Validation;
+
+use Magento\Framework\DataObjectFactory;
+use Magento\Framework\GraphQl\Exception\GraphQlInputException;
+use Magento\SendFriend\Model\SendFriend;
+
+class Validation
+{
+    /**
+     * @var SendFriend
+     */
+    private $sendFriend;
+    /**
+     * @var DataObjectFactory
+     */
+    private $dataObjectFactory;
+
+    public function __construct(
+        DataObjectFactory $dataObjectFactory,
+        SendFriend $sendFriend
+    ) {
+        $this->sendFriend = $sendFriend;
+        $this->dataObjectFactory = $dataObjectFactory;
+    }
+
+    /**
+     * @param $args
+     * @param array $recipientsArray
+     * @throws GraphQlInputException
+     */
+    public function validate($args, array $recipientsArray): void
+    {
+        $this->prepareDataForSendFriendValidation($args, $recipientsArray);
+        $validationResult = $this->sendFriend->validate();
+        if ($validationResult !== true) {
+            throw new GraphQlInputException(__(implode($validationResult)));
+        }
+        if ($this->sendFriend->getMaxSendsToFriend() && $this->sendFriend->isExceedLimit()) {
+            throw new GraphQlInputException(__('You can\'t send messages more than %1 times an hour.',
+                $this->sendFriend->getMaxSendsToFriend()
+            ));
+        }
+    }
+
+    private function prepareDataForSendFriendValidation(array $args, array $recipientsArray): void
+    {
+        $sender = $this->dataObjectFactory->create()->setData([
+            'name' => $args['input']['sender']['name'],
+            'email'=> $args['input']['sender']['email'],
+            'message' => $args['input']['sender']['message'],
+        ]);
+        $emails = [];
+        foreach ($recipientsArray['recipients'] as $recipient) {
+            $emails[] = $recipient['email'];
+        }
+        $recipients = $this->dataObjectFactory->create()->setData('emails', $emails);
+
+        $this->sendFriend->setData('_sender', $sender);
+        $this->sendFriend->setData('_recipients', $recipients);
+    }
+
+}