Merge pull request #99 from patchlevel/lazy-with-attribute

add lazy hydration feature

Author: DavidBadura

README.md

@@ -473,6 +473,29 @@ readonly class ProfileCreated
 }
 ```
 
+### Lazy
+
+Since PHP 8.4, it's been possible to lazy-hydrate objects. 
+That is, the actual hydration process occurs when the object is accessed.
+You can define for each class whether you want it to be lazy by using the `Lazy` attribute.
+
+```php
+use Patchlevel\Hydrator\Attribute\Lazy;
+
+#[Lazy]
+readonly class ProfileCreated 
+{
+    public function __construct(
+        public string $id,
+        public string $name,
+    ) {
+    }
+}
+```
+
+> [!NOTE]
+> If you are using a PHP version older than 8.4, the attribute will be ignored.
+
 ### Hooks
 
 Sometimes you need to do something before extract or after hydrate process.
@@ -623,6 +646,10 @@ final class ProfileCreated
 }
 ```
 
+> [!TIP]
+> Cryptography is very expensive in terms of performance, 
+> you can combine it with lazy to improve performance and only decrypt when you actually access the object.
+
 #### Configure Cryptography
 
 Here we show you how to configure the cryptography.

src/Attribute/Lazy.php

@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Patchlevel\Hydrator\Attribute;
+
+use Attribute;
+
+#[Attribute(Attribute::TARGET_CLASS)]
+final class Lazy
+{
+    public function __construct(
+        public readonly bool $enabled = true,
+    ) {
+    }
+}

src/Metadata/AttributeMetadataFactory.php

@@ -6,6 +6,7 @@
 
 use Patchlevel\Hydrator\Attribute\DataSubjectId;
 use Patchlevel\Hydrator\Attribute\Ignore;
+use Patchlevel\Hydrator\Attribute\Lazy;
 use Patchlevel\Hydrator\Attribute\NormalizedName;
 use Patchlevel\Hydrator\Attribute\PersonalData;
 use Patchlevel\Hydrator\Attribute\PostHydrate;
@@ -102,6 +103,7 @@ private function getClassMetadata(ReflectionClass $reflectionClass): ClassMetada
             $this->getSubjectIdField($reflectionClass),
             $this->getPostHydrateCallbacks($reflectionClass),
             $this->getPreExtractCallbacks($reflectionClass),
+            $this->getLazy($reflectionClass),
         );
 
         $parentMetadataClass = $reflectionClass->getParentClass();
@@ -214,6 +216,18 @@ private function getPreExtractCallbacks(ReflectionClass $reflection): array
         return $methods;
     }
 
+    /** @param ReflectionClass<object> $reflection */
+    private function getLazy(ReflectionClass $reflection): bool|null
+    {
+        $attributeReflectionList = $reflection->getAttributes(Lazy::class);
+
+        if ($attributeReflectionList === []) {
+            return null;
+        }
+
+        return $attributeReflectionList[0]->newInstance()->enabled;
+    }
+
     private function getFieldName(ReflectionProperty $reflectionProperty): string
     {
         $attributeReflectionList = $reflectionProperty->getAttributes(NormalizedName::class);
@@ -273,6 +287,7 @@ private function mergeMetadata(ClassMetadata $parent, ClassMetadata $child): Cla
             $parentDataSubjectIdField ?? $childDataSubjectIdField,
             array_merge($parent->postHydrateCallbacks(), $child->postHydrateCallbacks()),
             array_merge($parent->preExtractCallbacks(), $child->preExtractCallbacks()),
+            $child->lazy() ?? $parent->lazy(),
         );
     }
 

src/Metadata/ClassMetadata.php

@@ -13,6 +13,7 @@
  *     dataSubjectIdField: string|null,
  *     postHydrateCallbacks: list<CallbackMetadata>,
  *     preExtractCallbacks: list<CallbackMetadata>,
+ *     lazy: bool|null,
  * }
  * @template T of object = object
  */
@@ -30,6 +31,7 @@ public function __construct(
         private readonly string|null $dataSubjectIdField = null,
         private readonly array $postHydrateCallbacks = [],
         private readonly array $preExtractCallbacks = [],
+        private readonly bool|null $lazy = null,
     ) {
     }
 
@@ -63,6 +65,11 @@ public function preExtractCallbacks(): array
         return $this->preExtractCallbacks;
     }
 
+    public function lazy(): bool|null
+    {
+        return $this->lazy;
+    }
+
     public function dataSubjectIdField(): string|null
     {
         return $this->dataSubjectIdField;
@@ -94,6 +101,7 @@ public function __serialize(): array
             'dataSubjectIdField' => $this->dataSubjectIdField,
             'postHydrateCallbacks' => $this->postHydrateCallbacks,
             'preExtractCallbacks' => $this->preExtractCallbacks,
+            'lazy' => $this->lazy,
         ];
     }
 
@@ -105,5 +113,6 @@ public function __unserialize(array $data): void
         $this->dataSubjectIdField = $data['dataSubjectIdField'];
         $this->postHydrateCallbacks = $data['postHydrateCallbacks'];
         $this->preExtractCallbacks = $data['preExtractCallbacks'];
+        $this->lazy = $data['lazy'];
     }
 }

src/MetadataHydrator.php

@@ -16,6 +16,7 @@
 use Patchlevel\Hydrator\Metadata\ClassNotFound;
 use Patchlevel\Hydrator\Metadata\MetadataFactory;
 use Patchlevel\Hydrator\Normalizer\HydratorAwareNormalizer;
+use ReflectionClass;
 use ReflectionParameter;
 use Symfony\Component\EventDispatcher\EventDispatcher;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
@@ -27,6 +28,8 @@
 use function is_object;
 use function spl_object_id;
 
+use const PHP_VERSION_ID;
+
 final class MetadataHydrator implements Hydrator
 {
     /** @var array<int, class-string> */
@@ -36,6 +39,7 @@ public function __construct(
         private readonly MetadataFactory $metadataFactory = new AttributeMetadataFactory(),
         PayloadCryptographer|null $cryptographer = null,
         private EventDispatcherInterface|null $eventDispatcher = null,
+        private readonly bool $defaultLazy = false,
     ) {
         if (!$cryptographer) {
             return;
@@ -66,6 +70,33 @@ public function hydrate(string $class, array $data): object
             throw new ClassNotSupported($class, $e);
         }
 
+        if (PHP_VERSION_ID < 80400) {
+            return $this->doHydrate($metadata, $data);
+        }
+
+        $lazy = $metadata->lazy() ?? $this->defaultLazy;
+
+        if (!$lazy) {
+            return $this->doHydrate($metadata, $data);
+        }
+
+        return (new ReflectionClass($class))->newLazyProxy(
+            function () use ($metadata, $data): object {
+                return $this->doHydrate($metadata, $data);
+            },
+        );
+    }
+
+    /**
+     * @param ClassMetadata<T>     $metadata
+     * @param array<string, mixed> $data
+     *
+     * @return T
+     *
+     * @template T of object
+     */
+    private function doHydrate(ClassMetadata $metadata, array $data): object
+    {
         if ($this->eventDispatcher) {
             $data = $this->eventDispatcher->dispatch(new PreHydrate($data, $metadata))->data;
         }
@@ -110,7 +141,7 @@ public function hydrate(string $class, array $data): object
                     $value = $normalizer->denormalize($value);
                 } catch (Throwable $e) {
                     throw new DenormalizationFailure(
-                        $class,
+                        $metadata->className(),
                         $propertyMetadata->propertyName(),
                         $normalizer::class,
                         $e,
@@ -122,7 +153,7 @@ public function hydrate(string $class, array $data): object
                 $propertyMetadata->setValue($object, $value);
             } catch (TypeError $e) {
                 throw new TypeMismatch(
-                    $class,
+                    $metadata->className(),
                     $propertyMetadata->propertyName(),
                     $e,
                 );
@@ -234,6 +265,7 @@ private function promotedConstructorParametersWithDefaultValue(ClassMetadata $me
     public static function create(
         iterable $guessers = [],
         EventDispatcherInterface|null $eventDispatcher = null,
+        bool $defaultLazy = false,
     ): self {
         $guesser = new BuiltInGuesser();
 
@@ -250,6 +282,7 @@ public static function create(
             ),
             null,
             $eventDispatcher,
+            $defaultLazy,
         );
     }
 }

tests/Benchmark/HydratorBench.php

@@ -66,7 +66,7 @@ public function benchExtract1Object(): void
         $this->hydrator->extract($object);
     }
 
-    #[Bench\Revs(5)]
+    #[Bench\Revs(3)]
     public function benchHydrate1000Objects(): void
     {
         for ($i = 0; $i < 1_000; $i++) {
@@ -81,7 +81,7 @@ public function benchHydrate1000Objects(): void
         }
     }
 
-    #[Bench\Revs(5)]
+    #[Bench\Revs(3)]
     public function benchExtract1000Objects(): void
     {
         $object = new ProfileCreated(
@@ -98,7 +98,7 @@ public function benchExtract1000Objects(): void
         }
     }
 
-    #[Bench\Revs(5)]
+    #[Bench\Revs(3)]
     public function benchHydrate1000000Objects(): void
     {
         for ($i = 0; $i < 1_000_000; $i++) {
@@ -113,7 +113,7 @@ public function benchHydrate1000000Objects(): void
         }
     }
 
-    #[Bench\Revs(5)]
+    #[Bench\Revs(3)]
     public function benchExtract1000000Objects(): void
     {
         $object = new ProfileCreated(

tests/Benchmark/HydratorWithCryptographyBench.php

@@ -84,7 +84,7 @@ public function benchExtract1Object(): void
         $this->hydrator->extract($object);
     }
 
-    #[Bench\Revs(5)]
+    #[Bench\Revs(3)]
     public function benchHydrate1000Objects(): void
     {
         for ($i = 0; $i < 1_000; $i++) {
@@ -102,7 +102,7 @@ public function benchHydrate1000Objects(): void
         }
     }
 
-    #[Bench\Revs(5)]
+    #[Bench\Revs(3)]
     public function benchExtract1000Objects(): void
     {
         $object = new ProfileCreated(
@@ -119,7 +119,7 @@ public function benchExtract1000Objects(): void
         }
     }
 
-    #[Bench\Revs(5)]
+    #[Bench\Revs(3)]
     public function benchHydrate1000000Objects(): void
     {
         for ($i = 0; $i < 1_000_000; $i++) {
@@ -137,7 +137,7 @@ public function benchHydrate1000000Objects(): void
         }
     }
 
-    #[Bench\Revs(5)]
+    #[Bench\Revs(3)]
     public function benchExtract1000000Objects(): void
     {
         $object = new ProfileCreated(