fix(graphql): support nullable embedded relations in GraphQL types

src/GraphQl/Tests/Type/TypeBuilderTest.php

@@ -217,6 +217,30 @@ public function testGetResourceObjectTypeNestedInput(): void
         $wrappedType->config['fields']();
     }
 
+    public function testGetResourceObjectTypeNestedInputNullable(): void
+    {
+        $resourceMetadata = new ResourceMetadataCollection('resourceClass', []);
+        $this->typesContainerProphecy->has('customShortNameNullableNestedInput')->shouldBeCalled()->willReturn(false);
+        $this->typesContainerProphecy->set('customShortNameNullableNestedInput', Argument::type(InputObjectType::class))->shouldBeCalled();
+        $this->typesContainerProphecy->has('Node')->shouldBeCalled()->willReturn(false);
+        $this->typesContainerProphecy->set('Node', Argument::type(InterfaceType::class))->shouldBeCalled();
+
+        /** @var Operation $operation */
+        $operation = (new Mutation())->withName('custom')->withShortName('shortNameNullable')->withDescription('description nullable');
+        /** @var InputObjectType $resourceObjectType */
+        $resourceObjectType = $this->typeBuilder->getResourceObjectType('resourceClass', $resourceMetadata, $operation, true, false, 1, false);
+
+        $this->assertInstanceOf(InputObjectType::class, $resourceObjectType);
+        $this->assertSame('customShortNameNullableNestedInput', $resourceObjectType->name);
+        $this->assertSame('description nullable', $resourceObjectType->description);
+        $this->assertArrayHasKey('fields', $resourceObjectType->config);
+
+        $fieldsBuilderProphecy = $this->prophesize(FieldsBuilderEnumInterface::class);
+        $fieldsBuilderProphecy->getResourceObjectTypeFields('resourceClass', $operation, true, 1, null)->shouldBeCalled();
+        $this->fieldsBuilderLocatorProphecy->get('api_platform.graphql.fields_builder')->shouldBeCalled()->willReturn($fieldsBuilderProphecy->reveal());
+        $resourceObjectType->config['fields']();
+    }
+
     public function testGetResourceObjectTypeCustomMutationInputArgs(): void
     {
         $resourceMetadata = new ResourceMetadataCollection('resourceClass', []);

src/GraphQl/Tests/Type/TypeConverterTest.php

@@ -161,7 +161,7 @@ public function testConvertTypeInputResource(): void
         $this->resourceMetadataCollectionFactoryProphecy->create('dummy')->willReturn($graphqlResourceMetadata);
         $this->typeBuilderProphecy->isCollection($type)->willReturn(false);
         $this->propertyMetadataFactoryProphecy->create('rootClass', 'dummyProperty', Argument::type('array'))->shouldBeCalled()->willReturn((new ApiProperty())->withWritableLink(true));
-        $this->typeBuilderProphecy->getResourceObjectType('dummy', $graphqlResourceMetadata, $operation, true, false, 1)->shouldBeCalled()->willReturn($expectedGraphqlType);
+        $this->typeBuilderProphecy->getResourceObjectType('dummy', $graphqlResourceMetadata, $operation, true, false, 1, true)->shouldBeCalled()->willReturn($expectedGraphqlType);
 
         $graphqlType = $this->typeConverter->convertType($type, true, $operation, 'dummy', 'rootClass', 'dummyProperty', 1);
         $this->assertSame($expectedGraphqlType, $graphqlType);
@@ -179,7 +179,7 @@ public function testConvertTypeCollectionResource(Type $type, ObjectType $expect
 
         $this->typeBuilderProphecy->isCollection($type)->shouldBeCalled()->willReturn(true);
         $this->resourceMetadataCollectionFactoryProphecy->create('dummyValue')->shouldBeCalled()->willReturn($graphqlResourceMetadata);
-        $this->typeBuilderProphecy->getResourceObjectType('dummyValue', $graphqlResourceMetadata, $collectionOperation, false, false, 0)->shouldBeCalled()->willReturn($expectedGraphqlType);
+        $this->typeBuilderProphecy->getResourceObjectType('dummyValue', $graphqlResourceMetadata, $collectionOperation, false, false, 0, true)->shouldBeCalled()->willReturn($expectedGraphqlType);
 
         /** @var Operation $rootOperation */
         $rootOperation = (new Query())->withName('test');

src/GraphQl/Type/TypeBuilder.php

@@ -48,7 +48,7 @@ public function __construct(private readonly TypesContainerInterface $typesConta
     /**
      * {@inheritdoc}
      */
-    public function getResourceObjectType(?string $resourceClass, ResourceMetadataCollection $resourceMetadataCollection, Operation $operation, bool $input, bool $wrapped = false, int $depth = 0): GraphQLType
+    public function getResourceObjectType(?string $resourceClass, ResourceMetadataCollection $resourceMetadataCollection, Operation $operation, bool $input, bool $wrapped = false, int $depth = 0, bool $required = true): GraphQLType
     {
         $shortName = $operation->getShortName();
         $operationName = $operation->getName();
@@ -86,8 +86,8 @@ public function getResourceObjectType(?string $resourceClass, ResourceMetadataCo
 
         if ($this->typesContainer->has($shortName)) {
             $resourceObjectType = $this->typesContainer->get($shortName);
-            if (!($resourceObjectType instanceof ObjectType || $resourceObjectType instanceof NonNull)) {
-                throw new \LogicException(sprintf('Expected GraphQL type "%s" to be %s.', $shortName, implode('|', [ObjectType::class, NonNull::class])));
+            if (!($resourceObjectType instanceof ObjectType || $resourceObjectType instanceof NonNull || $resourceObjectType instanceof InputObjectType)) {
+                throw new \LogicException(sprintf('Expected GraphQL type "%s" to be %s.', $shortName, implode('|', [ObjectType::class, NonNull::class, InputObjectType::class])));
             }
 
             return $resourceObjectType;
@@ -156,7 +156,15 @@ public function getResourceObjectType(?string $resourceClass, ResourceMetadataCo
             'interfaces' => $wrapData ? [] : [$this->getNodeInterface()],
         ];
 
-        $resourceObjectType = $input ? GraphQLType::nonNull(new InputObjectType($configuration)) : new ObjectType($configuration);
+        if ($input) {
+            $resourceObjectType = new InputObjectType($configuration);
+            if ($required) {
+                $resourceObjectType = GraphQLType::nonNull($resourceObjectType);
+            }
+        } else {
+            $resourceObjectType = new ObjectType($configuration);
+        }
+
         $this->typesContainer->set($shortName, $resourceObjectType);
 
         return $resourceObjectType;

src/GraphQl/Type/TypeBuilderEnumInterface.php

@@ -16,8 +16,6 @@
 use ApiPlatform\Metadata\GraphQl\Operation;
 use ApiPlatform\Metadata\Resource\ResourceMetadataCollection;
 use GraphQL\Type\Definition\InterfaceType;
-use GraphQL\Type\Definition\NonNull;
-use GraphQL\Type\Definition\ObjectType;
 use GraphQL\Type\Definition\Type as GraphQLType;
 use Symfony\Component\PropertyInfo\Type;
 
@@ -31,9 +29,9 @@ interface TypeBuilderEnumInterface
     /**
      * Gets the object type of the given resource.
      *
-     * @return ObjectType|NonNull the object type, possibly wrapped by NonNull
+     * @return GraphQLType the object type, possibly wrapped by NonNull
      */
-    public function getResourceObjectType(?string $resourceClass, ResourceMetadataCollection $resourceMetadataCollection, Operation $operation, bool $input, bool $wrapped = false, int $depth = 0): GraphQLType;
+    public function getResourceObjectType(?string $resourceClass, ResourceMetadataCollection $resourceMetadataCollection, Operation $operation, bool $input, bool $wrapped = false, int $depth = 0, bool $required = false): GraphQLType;
 
     /**
      * Get the interface type of a node.

src/GraphQl/Type/TypeConverter.php

@@ -182,7 +182,9 @@ private function getResourceType(Type $type, bool $input, Operation $rootOperati
             throw new OperationNotFoundException();
         }
 
-        return $this->typeBuilder->getResourceObjectType($resourceClass, $resourceMetadataCollection, $operation, $input, false, $depth);
+        $required = $propertyMetadata?->isRequired() ?? true;
+
+        return $this->typeBuilder->getResourceObjectType($resourceClass, $resourceMetadataCollection, $operation, $input, false, $depth, $required);
     }
 
     private function resolveAstTypeNode(TypeNode $astTypeNode, string $fromType): ?GraphQLType