Introduction

This package provides a universal interface to manage PHP8 Attributes and help developers construct the attribute processors.

Installation

Install via composer.

composer require windwaker/attributes ^4.0

Use in Windwalker

In Windwalker framework, attributes works with DI Container.

At /etc/di.php, you can register your own attributes:

use Windwalker\Attributes\AttributeType;   // ...   'attributes' => [  MyAttribute::class => AttributeType::CLASSES  ]  ]   // ...

Then add it to your class:

 #[MyAttribute] class MyClass {  // ... }

Now you can inject this class or create it by container, attributes will auto work:

// Make it $app->make(MyClass::class);  $container->newInstance(MyClass::class);  // Or inject it public function __construct(MyClass $my) {}

Use as Standalone Component

Just create AttributesResolver object and register attributes.

use Windwalker\Attributes\AttributesResolver; use Windwalker\Attributes\AttributeType;  $attributes = new AttributesResolver(); $attributes->registerAttribute(\Wrapper::class, AttributeType::CLASSES);  // Now, try to wrap an object.  #[\Wrapper]  class Foo {   }  $foo = new \Foo(); $foo = $attributes->decorateObject($foo); $foo instanceof \Wrapper; $foo->inner instanceof \Foo;

Getting Started

First, you must create your own Attributes. This is a simple example wrapper to wrap any object.

use Windwalker\Attributes\AttributeHandler; use Windwalker\Attributes\AttributeInterface;  #[\Attribute(\Attribute::TARGET_CLASS)] class Wrapper implements AttributeInterface {  public object $inner;  public function __invoke(AttributeHandler $handler): callable  {  return function () use ($handler) {  $this->inner = $handler();  return $this;  };  } }

In __invoke(), always return a callback, you can do what you want in this callback.

The $handler() will return the value which return by previous attribute handler. All callbacks will be added to a stack and run after all attributes processed. This is very similar to middleware handler.

Then, register this attribute to resolver.

use Windwalker\Attributes\AttributesResolver; use Windwalker\Attributes\AttributeType;  $attributes = new AttributesResolver(); $attributes->registerAttribute(\Wrapper::class, AttributeType::CLASSES);  // Now, try to wrap an object.  #[\Wrapper]  class Foo {   }  $foo = new \Foo(); $foo = $attributes->decorateObject($foo); $foo instanceof \Wrapper; $foo->inner instanceof \Foo;