Use default value of PHP properties to Swagger doc

Add default and example information to swagger context if php properties
have default values so the exemple documentation section use these values.

Close #2363

Author: aaa2000

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

@@ -74,6 +74,10 @@
             <argument type="service" id="api_platform.metadata.property.metadata_factory.cached.inner" />
         </service>
 
+        <service id="api_platform.metadata.property.metadata_factory.default_property" decorates="api_platform.metadata.property.metadata_factory" decoration-priority="30" class="ApiPlatform\Core\Metadata\Property\Factory\DefaultPropertyMetadataFactory" public="false">
+            <argument type="service" id="api_platform.metadata.property.metadata_factory.default_property.inner" />
+        </service>
+
         <service id="ApiPlatform\Core\Metadata\Property\Factory\PropertyMetadataFactoryInterface" alias="api_platform.metadata.property.metadata_factory" />
 
         <!-- Cache -->

src/Metadata/Property/Factory/DefaultPropertyMetadataFactory.php

@@ -0,0 +1,60 @@
+<?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\Core\Metadata\Property\Factory;
+
+use ApiPlatform\Core\Exception\PropertyNotFoundException;
+use ApiPlatform\Core\Metadata\Property\PropertyMetadata;
+
+class DefaultPropertyMetadataFactory implements PropertyMetadataFactoryInterface
+{
+    private $decorated;
+
+    public function __construct(PropertyMetadataFactoryInterface $decorated = null)
+    {
+        $this->decorated = $decorated;
+    }
+
+    public function create(string $resourceClass, string $property, array $options = []): PropertyMetadata
+    {
+        if (null === $this->decorated) {
+            $propertyMetadata = new PropertyMetadata();
+        } else {
+            try {
+                $propertyMetadata = $this->decorated->create($resourceClass, $property, $options);
+            } catch (PropertyNotFoundException $propertyNotFoundException) {
+                $propertyMetadata = new PropertyMetadata();
+            }
+        }
+
+        try {
+            $reflectionClass = new \ReflectionClass($resourceClass);
+        } catch (\ReflectionException $reflectionException) {
+            return $propertyMetadata;
+        }
+
+        $defaultProperties = $reflectionClass->getDefaultProperties();
+
+        if (array_key_exists($property, $defaultProperties) && null !== ($defaultProperty = $defaultProperties[$property])) {
+            $attributes = $propertyMetadata->getAttributes() ?? [];
+            $attributes['swagger_context']['default'] = $defaultProperty;
+            if (!isset($attributes['swagger_context']['example'])) {
+                $attributes['swagger_context']['example'] = $defaultProperty;
+            }
+
+            return $propertyMetadata->withAttributes($attributes);
+        }
+
+        return $propertyMetadata;
+    }
+}

tests/Bridge/Symfony/Bundle/DependencyInjection/ApiPlatformExtensionTest.php

@@ -936,6 +936,7 @@ private function getPartialContainerBuilderProphecy($configuration = null)
             'api_platform.metadata.resource.metadata_factory.xml',
             'api_platform.metadata.resource.name_collection_factory.cached',
             'api_platform.metadata.resource.name_collection_factory.xml',
+            'api_platform.metadata.property.metadata_factory.default_property',
             'api_platform.negotiator',
             'api_platform.operation_method_resolver',
             'api_platform.operation_path_resolver.custom',

tests/Fixtures/TestBundle/Entity/DummyPropertyWithDefaultValue.php

@@ -0,0 +1,59 @@
+<?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\Core\Tests\Fixtures\TestBundle\Entity;
+
+use ApiPlatform\Core\Annotation\ApiResource;
+use Doctrine\ORM\Mapping as ORM;
+use Symfony\Component\Serializer\Annotation\Groups;
+
+/**
+ * DummyPropertyWithDefaultValue.
+ *
+ * @ORM\Entity
+ *
+ * @ApiResource(attributes={
+ *     "normalization_context"={"groups"={"dummy_read"}},
+ *     "denormalization_context"={"groups"={"dummy_write"}}
+ * })
+ */
+class DummyPropertyWithDefaultValue
+{
+    /**
+     * @var int
+     *
+     * @ORM\Id
+     * @ORM\Column(type="integer")
+     * @ORM\GeneratedValue(strategy="AUTO")
+     *
+     * @Groups("dummy_read")
+     */
+    private $id;
+
+    /**
+     * @var string
+     *
+     * @ORM\Column(nullable=true)
+     *
+     * @Groups({"dummy_read", "dummy_write"})
+     */
+    public $foo = 'foo';
+
+    /**
+     * @return int
+     */
+    public function getId()
+    {
+        return $this->id;
+    }
+}

tests/Metadata/Property/Factory/DefaultPropertyMetadataFactoryTest.php

@@ -0,0 +1,80 @@
+<?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\Core\Tests\Metadata\Property\Factory;
+
+use ApiPlatform\Core\Exception\PropertyNotFoundException;
+use ApiPlatform\Core\Metadata\Property\Factory\DefaultPropertyMetadataFactory;
+use ApiPlatform\Core\Metadata\Property\Factory\PropertyMetadataFactoryInterface;
+use ApiPlatform\Core\Metadata\Property\PropertyMetadata;
+use ApiPlatform\Core\Tests\Fixtures\TestBundle\Entity\DummyPropertyWithDefaultValue;
+use PHPUnit\Framework\TestCase;
+
+class DefaultPropertyMetadataFactoryTest extends TestCase
+{
+    public function testCreate()
+    {
+        $factory = new DefaultPropertyMetadataFactory();
+        $metadata = $factory->create(DummyPropertyWithDefaultValue::class, 'foo');
+
+        $shouldBe = [
+            'swagger_context' => [
+                'default' => 'foo',
+                'example' => 'foo',
+            ],
+        ];
+        $this->assertEquals($metadata->getAttributes(), $shouldBe);
+    }
+
+    public function testCreateShouldNotOverrideExampleIfAlreadyPresent()
+    {
+        $decoratedReturnProphecy = $this->prophesize(PropertyMetadataFactoryInterface::class);
+        $decoratedReturnProphecy->create(DummyPropertyWithDefaultValue::class, 'foo', [])
+            ->willReturn(new PropertyMetadata(null, 'A dummy', true, true, null, null, false, false, null, null, [
+                'swagger_context' => [
+                    'example' => 'foo example',
+                ],
+            ]))
+            ->shouldBeCalled();
+
+        $factory = new DefaultPropertyMetadataFactory($decoratedReturnProphecy->reveal());
+        $metadata = $factory->create(DummyPropertyWithDefaultValue::class, 'foo');
+
+        $shouldBe = [
+            'swagger_context' => [
+                'default' => 'foo',
+                'example' => 'foo example',
+            ],
+        ];
+        $this->assertEquals($metadata->getAttributes(), $shouldBe);
+    }
+
+    public function testClassDoesNotExist()
+    {
+        $factory = new DefaultPropertyMetadataFactory();
+        $metadata = $factory->create('\DoNotExist', 'foo');
+
+        $this->assertEquals(new PropertyMetadata(), $metadata);
+    }
+
+    public function testPropertyDoesNotExist()
+    {
+        $decoratedProphecy = $this->prophesize(PropertyMetadataFactoryInterface::class);
+        $decoratedProphecy->create(DummyPropertyWithDefaultValue::class, 'doNotExist', [])->willThrow(new PropertyNotFoundException());
+
+        $factory = new DefaultPropertyMetadataFactory($decoratedProphecy->reveal());
+        $metadata = $factory->create(DummyPropertyWithDefaultValue::class, 'doNotExist');
+
+        $this->assertEquals(new PropertyMetadata(), $metadata);
+    }
+}