Use InputUnionType for updating related existing resources

Author: alanpoulain

features/graphql/mutation.feature

@@ -122,6 +122,28 @@ Feature: GraphQL mutation support
     And the JSON node "data.createRelatedDummy.id" should be equal to "/related_dummies/2"
     And the JSON node "data.createRelatedDummy.clientMutationId" should be equal to "myId"
 
+  Scenario: Create an item and update a nested resource through a mutation
+    When I send the following GraphQL request:
+    """
+    mutation {
+      createRelationEmbedder(input: {paris: "paris", krondstadt: "Krondstadt", anotherRelated: {id: 2, symfony: "laravel"}, clientMutationId: "myId"}) {
+        id
+        anotherRelated {
+          id
+          symfony
+        }
+        clientMutationId
+      }
+    }
+    """
+    Then the response status code should be 200
+    And the response should be in JSON
+    And the header "Content-Type" should be equal to "application/json"
+    And the JSON node "data.createRelationEmbedder.id" should be equal to "/relation_embedders/1"
+    And the JSON node "data.createRelationEmbedder.anotherRelated.id" should be equal to "/related_dummies/2"
+    And the JSON node "data.createRelationEmbedder.anotherRelated.symfony" should be equal to "laravel"
+    And the JSON node "data.createRelationEmbedder.clientMutationId" should be equal to "myId"
+
   @dropSchema
   Scenario: Delete an item through a mutation
     When I send the following GraphQL request:

src/Bridge/Symfony/Bundle/Resources/config/graphql.xml

@@ -77,6 +77,10 @@
             <argument type="service" id="api_platform.item_data_provider" on-invalid="ignore" />
             <argument>%api_platform.allow_plain_identifiers%</argument>
 
+            <call method="setItemNormalizer">
+                <argument type="service" id="api_platform.serializer.normalizer.item" />
+            </call>
+
             <tag name="serializer.normalizer" priority="8" />
         </service>
     </services>

src/GraphQl/Serializer/ItemNormalizer.php

@@ -23,6 +23,7 @@
 
 use ApiPlatform\Core\Metadata\Property\PropertyMetadata;
 use ApiPlatform\Core\Serializer\AbstractItemNormalizer;
+use Symfony\Component\Serializer\Normalizer\DenormalizerInterface;
 
 /**
  * GraphQL normalizer.
@@ -34,6 +35,8 @@ final class ItemNormalizer extends AbstractItemNormalizer
     const FORMAT = 'graphql';
     const ITEM_KEY = '#item';
 
+    private $itemNormalizer;
+
     /**
      * {@inheritdoc}
      */
@@ -62,11 +65,24 @@ public function supportsNormalization($data, $format = null)
         return self::FORMAT === $format && parent::supportsNormalization($data, $format);
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function denormalize($data, $class, $format = null, array $context = [])
+    {
+        return $this->itemNormalizer->denormalize($data, $class, $format, $context);
+    }
+
     /**
      * {@inheritdoc}
      */
     public function supportsDenormalization($data, $type, $format = null)
     {
         return self::FORMAT === $format && parent::supportsDenormalization($data, $type, $format);
     }
+
+    public function setItemNormalizer(DenormalizerInterface $itemNormalizer)
+    {
+        $this->itemNormalizer = $itemNormalizer;
+    }
 }

tests/GraphQl/Serializer/ItemNormalizerTest.php

@@ -101,31 +101,25 @@ public function testNormalize()
 
     public function testDenormalize()
     {
-        $context = ['resource_class' => Dummy::class, 'api_allow_update' => true];
-
-        $propertyNameCollection = new PropertyNameCollection(['name']);
         $propertyNameCollectionFactoryProphecy = $this->prophesize(PropertyNameCollectionFactoryInterface::class);
-        $propertyNameCollectionFactoryProphecy->create(Dummy::class, [])->willReturn($propertyNameCollection)->shouldBeCalled();
-
-        $propertyMetadataFactory = new PropertyMetadata(null, null, true, true);
         $propertyMetadataFactoryProphecy = $this->prophesize(PropertyMetadataFactoryInterface::class);
-        $propertyMetadataFactoryProphecy->create(Dummy::class, 'name', [])->willReturn($propertyMetadataFactory)->shouldBeCalled();
-
         $iriConverterProphecy = $this->prophesize(IriConverterInterface::class);
-
         $resourceClassResolverProphecy = $this->prophesize(ResourceClassResolverInterface::class);
 
-        $serializerProphecy = $this->prophesize(SerializerInterface::class);
-        $serializerProphecy->willImplement(DenormalizerInterface::class);
-
         $normalizer = new ItemNormalizer(
             $propertyNameCollectionFactoryProphecy->reveal(),
             $propertyMetadataFactoryProphecy->reveal(),
             $iriConverterProphecy->reveal(),
             $resourceClassResolverProphecy->reveal()
         );
-        $normalizer->setSerializer($serializerProphecy->reveal());
 
-        $this->assertInstanceOf(Dummy::class, $normalizer->denormalize(['name' => 'hello'], Dummy::class, ItemNormalizer::FORMAT, $context));
+        $itemNormalizer = $this->prophesize(DenormalizerInterface::class);
+        $itemNormalizer->denormalize(['name' => 'hello'], Dummy::class, ItemNormalizer::FORMAT, [])
+            ->willReturn('denormalized')
+            ->shouldBeCalled()
+        ;
+        $normalizer->setItemNormalizer($itemNormalizer->reveal());
+
+        $normalizer->denormalize(['name' => 'hello'], Dummy::class, ItemNormalizer::FORMAT);
     }
 }