交响乐2 : multiple and dynamic database connection

Question

我对 SF2 很陌生，我想知道如何将多个数据库的连接管理到一个 bundle 中。目前我有这个解决方案 - 效果很好 - 但我不知道这是否是正确的方法......

在 myBundle\Ressource\config\config.yml 中:

doctrine:
dbal:
    default_connection:       default
    connections:
        default:
            dbname:           SERVER
            user:             root
            password:         null
            host:             localhost
        client:
            dbname:           CLIENT_134
            user:             root
            password:         null
            host:             localhost
orm:
    default_entity_manager:   default
    entity_managers:
        default:
            connection:       default
            mappings:
                MyBundle: ~
        client:
            connection:       client
            mappings:
                MyBundle: ~

然后，为了切换到其中一个 BD 或另一个，我这样做:

$O_ressource=  $this->get('doctrine')->getEntityManager('client');
$O_ressource=  $this->get('doctrine')->getEntityManager('default');

那么各位，你们认为这是管理这个问题的好方法吗？

我的第二个问题是:

如何建立动态数据库连接？我的意思是我的系统中有 100 个数据库，但我无法在 config.yml 文件中设置所有数据库。所以我希望能够动态更改数据库。

感谢您的帮助!

Answer 1

如果您使用ConnectionFactory，附加到连接的事件订阅者将停止工作，例如 stofDoctrineExtensions。

这是我的方法。我的 ConnectionFactory 有空连接和 EntityManager。在工作时，我只是用反射替换连接配置。适用于 SF 2.0.10 ;)

class YourService extends ContainerAware
{ 

  public function switchDatabase($dbName, $dbUser, $dbPass) 
  {
    $connection = $this->container->get(sprintf('doctrine.dbal.%s_connection', 'dynamic_conn'));
    $connection->close();

    $refConn = new \ReflectionObject($connection);
    $refParams = $refConn->getProperty('_params');
    $refParams->setAccessible('public'); //we have to change it for a moment

    $params = $refParams->getValue($connection);
    $params['dbname'] = $dbName;
    $params['user'] = $dbUser;
    $params['password'] = $dbPass;

    $refParams->setAccessible('private');
    $refParams->setValue($connection, $params);
    $this->container->get('doctrine')->resetEntityManager('dynamic_manager'); // for sure (unless you like broken transactions)
  }
}

更新:

针对 2.2/sf 2.3(无反射)的更优雅的解决方案，为 php5.4 创建(我喜欢新的数组初始值设定项:D)我们可以使用称为连接包装器的学说功能，请参阅http://docs.doctrine-project.org/projects/doctrine-dbal/en/latest/reference/portability.html

此示例使用 session 服务临时存储连接详细信息。

首先我们必须创建特殊的连接包装器:

namespace w3des\DoctrineBundle\Connection;

use Doctrine\DBAL\Connection;
use Symfony\Component\HttpFoundation\Session\Session;
use Doctrine\Common\EventManager;
use Doctrine\DBAL\Events;
use Doctrine\DBAL\Event\ConnectionEventArgs;

/*
 * @author Dawid zulus Pakula [zulus@w3des.net]
 */
class ConnectionWrapper extends Connection
{

const SESSION_ACTIVE_DYNAMIC_CONN = 'active_dynamic_conn';

/**
 * @var Session
 */
private $session;

/**
 * @var bool
 */
private $_isConnected = false;

/**
 * @param Session $sess
 */
public function setSession(Session $sess)
{
    $this->session = $sess;
}

public function forceSwitch($dbName, $dbUser, $dbPassword)
{
    if ($this->session->has(self::SESSION_ACTIVE_DYNAMIC_CONN)) {
        $current = $this->session->get(self::SESSION_ACTIVE_DYNAMIC_CONN);
        if ($current[0] === $dbName) {
            return;
        }
    }

    $this->session->set(self::SESSION_ACTIVE_DYNAMIC_CONN, [
        $dbName,
        $dbUser,
        $dbPass
    ]);

    if ($this->isConnected()) {
        $this->close();
    }
}

/**
 * {@inheritDoc}
 */
public function connect()
{
    if (! $this->session->has(self::SESSION_ACTIVE_DYNAMIC_CONN)) {
        throw new \InvalidArgumentException('You have to inject into valid context first');
    }
    if ($this->isConnected()) {
        return true;
    }

    $driverOptions = isset($params['driverOptions']) ? $params['driverOptions'] : array();

    $params = $this->getParams();
    $realParams = $this->session->get(self::SESSION_ACTIVE_DYNAMIC_CONN);
    $params['dbname'] = $realParams[0];
    $params['user'] = $realParams[1];
    $params['password'] = $realParams[2];

    $this->_conn = $this->_driver->connect($params, $params['user'], $params['password'], $driverOptions);

    if ($this->_eventManager->hasListeners(Events::postConnect)) {
        $eventArgs = new ConnectionEventArgs($this);
        $this->_eventManager->dispatchEvent(Events::postConnect, $eventArgs);
    }

    $this->_isConnected = true;

    return true;
}

/**
 * {@inheritDoc}
 */
public function isConnected()
{
    return $this->_isConnected;
}

/**
 * {@inheritDoc}
 */
public function close()
{
    if ($this->isConnected()) {
        parent::close();
        $this->_isConnected = false;
    }
}
}

接下来将其注册到您的学说配置中:

…

connections:
  dynamic:
    driver:   %database_driver%
    host:     %database_host%
    port:     %database_port%
    dbname:   'empty_database'
    charset:  UTF8
    wrapper_class: 'w3des\DoctrineBundle\Connection\ConnectionWrapper'

我们的 ConnectionWrapper 已正确注册。现在 session 注入(inject)。

首先创建特殊的 CompilerPass 类:

namespace w3des\DoctrineBundle\DependencyInjection\CompilerPass;

use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\DependencyInjection\Definition;
use Symfony\Component\DependencyInjection\Reference;

class ConnectionCompilerPass implements CompilerPassInterface
{

/**
 * {@inheritDoc}
 */
public function process(ContainerBuilder $container)
{
    $connection = $container
    ->getDefinition('doctrine.dbal.dynamic_connection')
    ->addMethodCall('setSession', [
        new Reference('session')
    ]);
}
}

我们在 *Bundle 类中记录新的编译器类:

public function build(ContainerBuilder $container)
{
    parent::build($container);
    $container->addCompilerPass(new ConnectionCompilerPass());
}

这就是全部!

将根据 session 属性按需创建连接。

要切换数据库，只需使用:

$this->get('doctrine.dbal.dynamic_connection')->forceSwitch($dbname, $dbuser, $dbpass);

优点

1. 不再反射(reflection)
2. 按需创作
3. 优雅而有力

缺点

1. 您必须手动清理实体管理器，或为此创建特殊的条令事件
2. 更多代码