如何在 slim 4 中设置和注入多个 PDO 数据库连接？

Question

我可以创建一个实例PDO并成功注入它。我PDO::class直接定义了并将其注入到构造函数中__construct(PDO $pdo)。我需要类似的东西PDO1::class并按PDO2::class如下方式注入它：__construct(PDO1 $pdo1, PDO2 $pdo2)但这显然不起作用。只有一个PDO类，我需要做的是它的 2 个具有不同数据库凭据的实例。
最好的方法是什么？

我通过这样的 PDO 设置了一个数据库定义，它可以工作：

文件： dependencies.php

use DI\ContainerBuilder;
use Psr\Container\ContainerInterface;

return function (ContainerBuilder $containerBuilder) {
    $containerBuilder->addDefinitions([
        PDO::class => function (ContainerInterface $c) {
            $dbSettings = $c->get('settings')['db1'];
            $dsn = 'mysql:host=' . $dbSettings['host'] . ';dbname=' . $dbSettings['dbname'];
            $options = [
                PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
                PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
                PDO::ATTR_EMULATE_PREPARES => false,
            ];
            return new PDO($dsn, $dbSettings['user'], $dbSettings['pass'], $options);
        },
    ]);
};

文件： index.php

...
// Set up dependencies
$dependencies = require __DIR__ . '/../app/dependencies.php';
$dependencies($containerBuilder);
// Build PHP-DI Container instance
$container = $containerBuilder->build();
// Set container to create App with on AppFactory
AppFactory::setContainer($container);
// Instantiate the app
$app = AppFactory::create();
...

文件 SomeRepository.php

use PDO;

class SomeRepository{

    protected $pdo;

    public function __construct(PDO $pdo) {
        $this->pdo = $pdo;
    }
}

我在这篇文章中看到过这样的事情：

return function (ContainerBuilder $containerBuilder) {
    $containerBuilder->addDefinitions([
        'db1' => function (ContainerInterface $c) {
            $db1Settings = $c->get('settings')['db1'];
            $dsn = 'mysql:host=' . $db1Settings['host'] . ';dbname=' . $db1Settings['dbname'];
            $options = [ ... ];
            return new PDO($dsn, $db1Settings['user'], $db1Settings['pass'],$options);
        },
        'db2' => function (ContainerInterface $c) {
            $db2Settings = $c->get('settings')['db2'];
            $dsn = 'mysql:host=' . $db2Settings['host'] . ';dbname=' . $db2Settings['dbname'];
            $options = [ ... ];
            return new PDO($dsn, $db2Settings['user'], $db2Settings['pass'],$options);
        },

    ]);
};

但这是最好的方法吗？以及如何在不必注入整个容器的情况下访问存储库类中的连接？

Answer 1

您有多种选择：

1. 扩展 PDO
2. 自动装配对象

1. 扩展 PDO

use PDO;

class PDO2 extends PDO
{
    // must be empty
}

容器定义：

use PDO2;

// ...

return [
    PDO::class => function (ContainerInterface $container) {
        return new PDO(...);
    },

    PDO2::class => function (ContainerInterface $container) {
        return new PDO2(...);
    },
];

用法

use PDO2;

// ...

return [
    PDO::class => function (ContainerInterface $container) {
        return new PDO(...);
    },

    PDO2::class => function (ContainerInterface $container) {
        return new PDO2(...);
    },
];

2. 自动装配对象

见马修那不勒斯的回答：https : //stackoverflow.com/a/57758106/1461181