laravel 中实现注解注入
创建注解类
<?php
declare(strict_types=1);
namespace App\Support\Attributes;
#[\Attribute(\Attribute::TARGET_PROPERTY)]
readonly class Injection
{
    public function __construct(
        public ?string $propertyType = null,
        public array $parameters = []
    ) {}
}
引导解析注解
<?php
declare(strict_types=1);
namespace App\Providers;
use App\Support\Attributes\Injection;
use Illuminate\Foundation\Application;
use Illuminate\Support\ServiceProvider;
class AppServiceProvider extends ServiceProvider
{
    public function register(): void {}
    public function boot(): void
    {
        $this->injection();
    }
    private function injection(): void
    {
        $this->app->resolving(static function (mixed $object, Application $app): void {
            if (! \is_object($object)) {
                return;
            }
            $class = str($object::class);
            if (
                ! $class->is(config('services.injection.only'))
                || $class->is(config('services.injection.except'))
            ) {
                return;
            }
            $reflectionObject = new \ReflectionObject($object);
            foreach ($reflectionObject->getProperties() as $reflectionProperty) {
                if (! $reflectionProperty->isDefault() || $reflectionProperty->isStatic()) {
                    continue;
                }
                $attributes = $reflectionProperty->getAttributes(Injection::class);
                if ($attributes === []) {
                    continue;
                }
                /** @var Injection $injection */
                $injection = $attributes[0]->newInstance();
                $propertyType = value(static function () use ($injection, $reflectionProperty, $reflectionObject): string {
                    if ($injection->propertyType) {
                        return $injection->propertyType;
                    }
                    $reflectionPropertyType = $reflectionProperty->getType();
                    if ($reflectionPropertyType instanceof \ReflectionNamedType && ! $reflectionPropertyType->isBuiltin()) {
                        return $reflectionPropertyType->getName();
                    }
                    throw new \LogicException(\sprintf(
                        'Attribute [%s] of %s miss a argument, or %s must be a non-built-in named type.',
                        Injection::class,
                        $property = "property [{$reflectionObject->getName()}::\${$reflectionProperty->getName()}]",
                        $property,
                    ));
                });
                $reflectionProperty->isPublic() or $reflectionProperty->setAccessible(true);
                $reflectionProperty->setValue($object, $app->make($propertyType, $injection->parameters));
            }
        });
    }
}
配置解析范围(可选)
config/services.php
<?php
return [
    // ...
    'injection' => [
        'only' => [
            'App\*',
        ],
        'except' => [
            'App\Support\Macros\*',
        ],
    ],
];
使用
示例
<?php
declare(strict_types=1);
namespace App\Console\Commands;
use App\Support\Attributes\Injection;
use App\Support\HmacSigner;
use Illuminate\Config\Repository;
class TestCommand extends \Illuminate\Console\Command
{
    protected $signature = 'test';
    #[Injection('path.storage')]
    private string $storagePath;
    #[Injection(parameters: ['secret' => 'secret...'])]
    private HmacSigner $hmacSigner;
    #[Injection(Repository::class)]
    private Repository $repositoryOfInjectionPropertyType;
    #[Injection('config')]
    private Repository $repositoryOfInjectionInstanceKey;
    #[Injection]
    private Repository $repositoryOfReflectionPropertyType;
    public function handle(): void
    {
        dump(
            $this->storagePath,
            $this->hmacSigner,
            $this->repositoryOfInjectionPropertyType->get('services.injection'),
            $this->repositoryOfInjectionInstanceKey->get('services.injection.only'),
            $this->repositoryOfReflectionPropertyType->get('services.injection.except'),
        );
    }
}
输出
╰─ ./artisan test                                                                                ─╯
"/Users/yaozm/Documents/wwwroot/laravel-skeleton/storage" // app/Console/Commands/TestCommand.php:32
App\Support\HmacSigner {#2045
  -secret: "secret..."
  -algo: "sha256"
} // app/Console/Commands/TestCommand.php:32
array:2 [
  "only" => array:1 [
    0 => "App\*"
  ]
  "except" => array:1 [
    0 => "App\Support\Macros\*"
  ]
] // app/Console/Commands/TestCommand.php:32
array:1 [
  0 => "App\*"
] // app/Console/Commands/TestCommand.php:32
array:1 [
  0 => "App\Support\Macros\*"
] // app/Console/Commands/TestCommand.php:32
与依赖注入比较
| 功能 | 注解注入 | 依赖注入 | 
|---|---|---|
| 标量类型 | 已支持 | 未支持 | 
| 传参 | 已支持 | 未支持 | 
相关连接
- app/Providers/AppServiceProvider.php#L680-L747
 - app/Support/Attributes/Injection.php
 - app/Support/HmacSigner.php