使用自定义 Doctrine 2 hydrator 进行依赖注入

Question

我在 Symfony 2 项目中的 Doctrine 2 中设置了一个自定义水合器，但要让它完成它需要的工作，它需要另一个服务。 documentation for custom hydrators 只展示了如何提供 hydrator 类，因此无法注入依赖项。

例如：

$em->getConfiguration()->addCustomHydrationMode('CustomHydrator', 'MyProject\Hydrators\CustomHydrator');

我怀疑 Doctrine 正在初始化 hydrator 本身，因此任何依赖项都需要首先通过其他一些 Doctrine 类。

有没有办法提供自定义的“水合工厂”或类似于 Doctrine 的允许注入额外依赖项的方法？如果没有此功能，自定义水合器似乎相当有限。

---

答案：感谢 Denis V

我得到这个工作如下。我无法发布实际代码，所以我将一些虚拟占位符放在一起，以便您查看它是如何组合在一起的。

src/Acme/ExampleBundle/resources/config/services.yml

services:
    doctrine.orm.entity_manager.abstract:
        class:          Acme\ExampleBundle\Entity\DoctrineEntityManager
        factory_class:  Acme\ExampleBundle\Entity\DoctrineEntityManager
        factory_method: create
        abstract:       true
        calls:
            - [ setMyDependency, [@acme.my_custom_service]]

src/Acme/ExampleBundle/Entity/DoctrineEntityManager.php

namespace Acme\ExampleBundle\Entity;

use Acme\ExampleBundle\Hydrator\MyHydrator;
use Doctrine\Common\EventManager;
use Doctrine\DBAL\Connection;
use Doctrine\ORM\Configuration;
use Doctrine\ORM\EntityManager as BaseEntityManager;
use Doctrine\ORM\ORMException;
use Doctrine\ORM\Query;

class DoctrineEntityManager extends BaseEntityManager
{
    protected $myDependency;

    /**
     * Note: This must be redefined as Doctrine's own entity manager has its own class name hardcoded in.
     */
    public static function create($conn, Configuration $config, EventManager $eventManager = null)
    {
        if (!$config->getMetadataDriverImpl()) {
            throw ORMException::missingMappingDriverImpl();
        }

        switch (true) {
            case (is_array($conn)):
                $conn = \Doctrine\DBAL\DriverManager::getConnection(
                    $conn, $config, ($eventManager ?: new EventManager())
                );
                break;

            case ($conn instanceof Connection):
                if ($eventManager !== null && $conn->getEventManager() !== $eventManager) {
                     throw ORMException::mismatchedEventManager();
                }
                break;

            default:
                throw new \InvalidArgumentException("Invalid argument: " . $conn);
        }

        return new self($conn, $config, $conn->getEventManager());
    }

    public function setMyDependency($myCustomService)
    {
        $this->myDependency = $myCustomService;
    }

    public function newHydrator($hydrationMode)
    {
        if ($hydrationMode == 'MyHydrationMode') {
            return new MyHydrator($this, $this->myDependency);
        }

        return parent::newHydrator($hydrationMode);
    }
}

src/Acme/ExampleBundle/Hydrator/MyHydrator.php

namespace Acme\ExampleBundle\Hydrator;

use Doctrine\ORM\EntityManager;
use Doctrine\ORM\Internal\Hydration\ObjectHydrator;

class MyHydrator extends ObjectHydrator
{
    protected $myDependency;

    public __construct(EntityManager $em, $myDependency)
    {
        parent::__construct($em);

        $this->myDependency = $myDependency;
    }

    protected function hydrateAllData()
    {
        /* hydration stuff with my dependency here */
    }
}

Answer 1

尝试在你的 config.yml 中添加它

doctrine:
    orm:
        hydrators:
            CustomHydrator: MyProject\Hydrators\CustomHydrator

更新

由于您无法向 Hydrator 本身注入任何东西，因此您可以创建一个自定义 EntityManager（您自己建议）。

可以这样：

services:  
    name_of_your_custom_manager:
        class: %doctrine.orm.entity_manager.class%
        factory_service:  doctrine
        factory_method:   getManager
        arguments: ["name_of_your_custom_manager"]
        calls:
            - [ setCustomDependency, ["@acme_bundle.custom_dependency"] ]

Answer 2

非常好的答案，但请注意，Doctrine 维护者明确表示 not to extend Doctrine\ORM\EntityManager，我想他们将来会最终强制执行。

因此，这里没有违反规则的建议解决方案是更清洁的解决方案：

<?php

declare(strict_types=1);

namespace App\Doctrine\ORM;

use Doctrine\Common\EventManager;
use Doctrine\DBAL\Connection;
use Doctrine\ORM\Configuration;
use Doctrine\ORM\Decorator\EntityManagerDecorator;
use Doctrine\ORM\EntityManagerInterface;
use Doctrine\ORM\ORMException;

class EntityManager extends EntityManagerDecorator
{
    public function __construct(EntityManagerInterface $wrapped)
    {
        parent::__construct($wrapped);
    }

    public static function create($conn, Configuration $config, EventManager $eventManager = null)
    {
        if ( ! $config->getMetadataDriverImpl()) {
            throw ORMException::missingMappingDriverImpl();
        }

        switch (true) {
            case (is_array($conn)):
                $conn = \Doctrine\DBAL\DriverManager::getConnection(
                    $conn, $config, ($eventManager ?: new EventManager())
                );
                break;

            case ($conn instanceof Connection):
                if ($eventManager !== null && $conn->getEventManager() !== $eventManager) {
                    throw ORMException::mismatchedEventManager();
                }
                break;

            default:
                throw new \InvalidArgumentException("Invalid argument: " . $conn);
        }

        return new EntityManager($conn, $config, $conn->getEventManager());
    }
}

现在在你的 services.xml 文件中定义这个服务来装饰你想要的实体管理器：

<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">


    <services>
        <defaults autowire="true" autoconfigure="true" public="false" />

        <service
            id="decorated.doctrine.orm.default_entity_manager"
            class="App\Doctrine\ORM\EntityManager"
            decorates="doctrine.orm.default_entity_manager"
        >
            <argument type="service" id="decorated.doctrine.orm.default_entity_manager.inner" />
        </service>

    </services>
</container>