4 - Extend SubjectPresenter with aggregate fields + add show endpoint

src/Controller/Api/SubjectController.php

@@ -54,6 +54,22 @@ class SubjectController extends AbstractController
         return $this->json(null, 201);
     }
 
+    #[Route('/api/subjects/{id}', methods: ['GET'])]
+    public function show(
+        int $id,
+        SubjectRepository $repository,
+        SubjectPresenter $presenter,
+        OutputService $output,
+    ): JsonResponse {
+        $subject = $repository->find($id);
+
+        if ($subject === null) {
+            return $this->json($output->error(['UNKNOWN_SUBJECT']), 404);
+        }
+
+        return $this->json($output->success(['subject' => $presenter->present($subject)]));
+    }
+
     #[Route('/api/subjects/{id}', methods: ['PATCH'])]
     public function update(
         int $id,

src/Factory/RatingFactory.php

@@ -32,6 +32,8 @@ final class RatingFactory extends PersistentObjectFactory
     protected function defaults(): array|callable
     {
         return [
+            'score' => self::faker()->numberBetween(1, 5),
+            'note' => self::faker()->optional()->sentence() ?? '',
             'subject' => RestaurantFactory::new(),
             'user' => UserFactory::new(),
         ];

src/Presenter/SubjectPresenter.php

@@ -15,6 +15,10 @@ class SubjectPresenter
      */
     public function present(Subject $subject): array
     {
+        $ratings = $subject->getRatings()->toArray();
+
+        usort($ratings, fn($a, $b) => $b->getCreatedAt() <=> $a->getCreatedAt());
+
         return [
             'id' => $subject->getId(),
             'name' => $subject->getName(),
@@ -24,13 +28,32 @@ class SubjectPresenter
                 'id' => $subject->getCreatedBy()->getId(),
                 'email' => $subject->getCreatedBy()->getEmail(),
             ],
+            'ratingCount' => count($ratings),
+            'averageScore' => $this->computeAverage($ratings),
             'ratings' => array_map(
                 fn($r) => $this->ratingPresenter->present($r),
-                $subject->getRatings()->toArray()
+                $ratings
             ),
         ];
     }
 
+    /**
+     * @param array<\App\Entity\Rating> $ratings
+     */
+    private function computeAverage(array $ratings): ?float
+    {
+        $scores = array_filter(
+            array_map(fn($r) => $r->getScore(), $ratings),
+            fn($s) => $s !== null
+        );
+
+        if (count($scores) === 0) {
+            return null;
+        }
+
+        return round(array_sum($scores) / count($scores), 1);
+    }
+
     /**
      * @param iterable<Subject> $subjects
      * @return array<int, array<string, mixed>>

tests/Application/Controller/Api/SubjectControllerTest.php

@@ -4,6 +4,7 @@ namespace App\Tests\Application\Controller\Api;
 
 use App\Entity\Restaurant;
 use App\Entity\Subject;
+use App\Factory\RatingFactory;
 use App\Factory\RestaurantFactory;
 use App\Factory\UserFactory;
 use App\Repository\SubjectRepository;
@@ -39,6 +40,38 @@ class SubjectControllerTest extends WebTestCase
         $this->assertNotNull($subject['longitude']);
     }
 
+    public function testShow(): void
+    {
+        $client = static::createClient();
+
+        $user = UserFactory::createOne();
+        $client->loginUser($user);
+
+        $subject = RestaurantFactory::createOne(['createdBy' => $user]);
+
+        RatingFactory::createOne(['subject' => $subject, 'score' => 4, 'user' => $user]);
+        RatingFactory::createOne(['subject' => $subject, 'score' => 2, 'user' => UserFactory::createOne()]);
+
+        $client->request('GET', '/api/subjects/' . $subject->getId(), server: ['CONTENT_TYPE' => 'application/json']);
+
+        $data = json_decode($client->getResponse()->getContent(), true);
+
+        $this->assertResponseIsSuccessful();
+        $this->assertSame($subject->getId(), $data['payload']['subject']['id']);
+        $this->assertSame($subject->getName(), $data['payload']['subject']['name']);
+        $this->assertCount(2, $data['payload']['subject']['ratings']);
+        $this->assertSame(2, $data['payload']['subject']['ratingCount']);
+        $this->assertEquals(3.0, $data['payload']['subject']['averageScore']);
+
+        $rating = $data['payload']['subject']['ratings'][0];
+        $this->assertArrayHasKey('id', $rating);
+        $this->assertArrayHasKey('score', $rating);
+        $this->assertArrayHasKey('note', $rating);
+        $this->assertArrayHasKey('createdAt', $rating);
+        $this->assertArrayHasKey('user', $rating);
+        $this->assertArrayHasKey('id', $rating['user']);
+    }
+
     public function testCreate(): void
     {
         $client = static::createClient();