Mail drivers: Separate definition from validation

src/Api/Controller/ShowMailSettingsController.php

@@ -0,0 +1,52 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Api\Controller;
+
+use Flarum\Api\Serializer\MailSettingsSerializer;
+use Flarum\Settings\SettingsRepositoryInterface;
+use Flarum\User\AssertPermissionTrait;
+use Illuminate\Contracts\Validation\Factory;
+use Psr\Http\Message\ServerRequestInterface;
+use Tobscure\JsonApi\Document;
+
+class ShowMailSettingsController extends AbstractShowController
+{
+    use AssertPermissionTrait;
+
+    /**
+     * {@inheritdoc}
+     */
+    public $serializer = MailSettingsSerializer::class;
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function data(ServerRequestInterface $request, Document $document)
+    {
+        $this->assertAdmin($request->getAttribute('actor'));
+
+        $drivers = array_map(function ($driver) {
+            return self::$container->make($driver);
+        }, self::$container->make('mail.supported_drivers'));
+
+        $settings = self::$container->make(SettingsRepositoryInterface::class);
+        $configured = self::$container->make('flarum.mail.configured_driver');
+        $actual = self::$container->make('mail.driver');
+        $validator = self::$container->make(Factory::class);
+
+        $errors = $configured->validate($settings, $validator);
+
+        return [
+            'drivers' => $drivers,
+            'sending' => $actual->canSend(),
+            'errors' => $errors,
+        ];
+    }
+}