Use exception handlers instead of JsonApiSerializableInterface

src/Api/ErrorHandler.php

@@ -0,0 +1,45 @@
+<?php
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Api;
+
+use Exception;
+use Tobscure\JsonApi\Document;
+use Tobscure\JsonApi\ErrorHandler as JsonApiErrorHandler;
+
+class ErrorHandler
+{
+    /**
+     * @var JsonApiErrorHandler
+     */
+    protected $errorHandler;
+
+    /**
+     * @param JsonApiErrorHandler $errorHandler
+     */
+    public function __construct(JsonApiErrorHandler $errorHandler)
+    {
+        $this->errorHandler = $errorHandler;
+    }
+
+    /**
+     * @param Exception $e
+     * @return JsonApiResponse
+     */
+    public function handle(Exception $e)
+    {
+        $response = $this->errorHandler->handle($e);
+
+        $document = new Document;
+        $document->setErrors($response->getErrors());
+
+        return new JsonApiResponse($document, $response->getStatus());
+    }
+}