fix(jsonapi): handle missing attributes in ErrorNormalizer

features/jsonapi/errors.feature

@@ -61,3 +61,13 @@ Feature: JSON API error handling
     And the JSON node "errors[0].status" should be equal to 404
     And the JSON node "errors[0].detail" should exist
     And the JSON node "errors[0].type" should exist
+
+  Scenario: Get a proper error when ItemNotFoundException is thrown from a provider
+    When I send a "GET" request to "/jsonapi_error_test/nonexistent"
+    Then the response status code should be 404
+    And the response should be in JSON
+    And the header "Content-Type" should be equal to "application/vnd.api+json; charset=utf-8"
+    And the JSON node "errors" should exist
+    And the JSON node "errors[0].status" should exist
+    And the JSON node "errors[0].title" should exist
+    And the JSON node "errors[0].id" should exist

src/JsonApi/Serializer/ErrorNormalizer.php

@@ -35,6 +35,15 @@ public function __construct(private ?NormalizerInterface $itemNormalizer = null)
     public function normalize(mixed $object, ?string $format = null, array $context = []): array
     {
         $jsonApiObject = $this->itemNormalizer->normalize($object, $format, $context);
+
+        if (!isset($jsonApiObject['data']['attributes'])) {
+            return ['errors' => [[
+                'id' => $jsonApiObject['data']['id'] ?? uniqid('error_', true),
+                'status' => (string) (method_exists($object, 'getStatusCode') ? $object->getStatusCode() : 500),
+                'title' => method_exists($object, 'getMessage') ? $object->getMessage() : 'An error occurred',
+            ]]];
+        }
+
         $error = $jsonApiObject['data']['attributes'];
         $error['id'] = $jsonApiObject['data']['id'];
         if (isset($error['type'])) {

tests/Fixtures/TestBundle/ApiResource/JsonApiErrorTestResource.php

@@ -0,0 +1,36 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Fixtures\TestBundle\ApiResource;
+
+use ApiPlatform\Metadata\ApiProperty;
+use ApiPlatform\Metadata\ApiResource;
+use ApiPlatform\Metadata\Get;
+use ApiPlatform\Tests\Fixtures\TestBundle\State\JsonApiErrorTestProvider;
+
+#[ApiResource(
+    operations: [
+        new Get(
+            uriTemplate: '/jsonapi_error_test/{id}',
+            provider: JsonApiErrorTestProvider::class,
+        ),
+    ],
+    formats: ['jsonapi' => ['application/vnd.api+json']],
+)]
+class JsonApiErrorTestResource
+{
+    #[ApiProperty(identifier: true)]
+    public string $id;
+
+    public string $name;
+}

tests/Fixtures/TestBundle/State/JsonApiErrorTestProvider.php

@@ -0,0 +1,37 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Fixtures\TestBundle\State;
+
+use ApiPlatform\Metadata\Exception\ItemNotFoundException;
+use ApiPlatform\Metadata\Operation;
+use ApiPlatform\State\ProviderInterface;
+use ApiPlatform\Tests\Fixtures\TestBundle\ApiResource\JsonApiErrorTestResource;
+
+class JsonApiErrorTestProvider implements ProviderInterface
+{
+    public function provide(Operation $operation, array $uriVariables = [], array $context = []): object|array|null
+    {
+        $id = $uriVariables['id'] ?? null;
+
+        if ('existing' === $id) {
+            $resource = new JsonApiErrorTestResource();
+            $resource->id = $id;
+            $resource->name = 'Existing Resource';
+
+            return $resource;
+        }
+
+        throw new ItemNotFoundException(\sprintf('Resource "%s" not found.', $id));
+    }
+}