composer require api-platform/core

app/config/bundles.php

@@ -10,4 +10,5 @@ return [
     Symfony\Bundle\WebProfilerBundle\WebProfilerBundle::class => ['dev' => true, 'test' => true],
     Symfony\WebpackEncoreBundle\WebpackEncoreBundle::class => ['all' => true],
     Sensio\Bundle\FrameworkExtraBundle\SensioFrameworkExtraBundle::class => ['all' => true],
+    ApiPlatform\Core\Bridge\Symfony\Bundle\ApiPlatformBundle::class => ['all' => true],
 ];

app/config/packages/api_platform.yaml

@@ -0,0 +1,7 @@
+api_platform:
+    mapping:
+        paths: ['%kernel.project_dir%/src/Entity']
+    patch_formats:
+        json: ['application/merge-patch+json']
+    swagger:
+        versions: [3]

app/config/routes/api_platform.yaml

@@ -0,0 +1,4 @@
+api_platform:
+    resource: .
+    type: api_platform
+    prefix: /api