34. Advanced Configuration

The configuration of the EntityManager requires a Doctrine\ORM\Configuration instance as well as some database connection parameters. This example shows all the potential steps of configuration.

<?php
use Doctrine\ORM\EntityManager,
    Doctrine\ORM\Configuration;

// ...

if ($applicationMode == "development") {
    $cache = new \Doctrine\Common\Cache\ArrayCache;
} else {
    $cache = new \Doctrine\Common\Cache\ApcCache;
}

$config = new Configuration;
$config->setMetadataCacheImpl($cache);
$driverImpl = $config->newDefaultAnnotationDriver('/path/to/lib/MyProject/Entities');
$config->setMetadataDriverImpl($driverImpl);
$config->setQueryCacheImpl($cache);
$config->setProxyDir('/path/to/myproject/lib/MyProject/Proxies');
$config->setProxyNamespace('MyProject\Proxies');

if ($applicationMode == "development") {
    $config->setAutoGenerateProxyClasses(true);
} else {
    $config->setAutoGenerateProxyClasses(false);
}

$connectionOptions = array(
    'driver' => 'pdo_sqlite',
    'path' => 'database.sqlite'
);

$em = EntityManager::create($connectionOptions, $config);

Note

Do not use Doctrine without a metadata and query cache! Doctrine is optimized for working with caches. The main parts in Doctrine that are optimized for caching are the metadata mapping information with the metadata cache and the DQL to SQL conversions with the query cache. These 2 caches require only an absolute minimum of memory yet they heavily improve the runtime performance of Doctrine. The recommended cache driver to use with Doctrine is APC. APC provides you with an opcode-cache (which is highly recommended anyway) and a very fast in-memory cache storage that you can use for the metadata and query caches as seen in the previous code snippet.

34.1. Configuration Options

The following sections describe all the configuration options available on a Doctrine\ORM\Configuration instance.

34.1.1. Proxy Directory (*REQUIRED*)

<?php
$config->setProxyDir($dir);
$config->getProxyDir();

Gets or sets the directory where Doctrine generates any proxy classes. For a detailed explanation on proxy classes and how they are used in Doctrine, refer to the “Proxy Objects” section further down.

34.1.2. Proxy Namespace (*REQUIRED*)

<?php
$config->setProxyNamespace($namespace);
$config->getProxyNamespace();

Gets or sets the namespace to use for generated proxy classes. For a detailed explanation on proxy classes and how they are used in Doctrine, refer to the “Proxy Objects” section further down.

34.1.3. Metadata Driver (*REQUIRED*)

<?php
$config->setMetadataDriverImpl($driver);
$config->getMetadataDriverImpl();

Gets or sets the metadata driver implementation that is used by Doctrine to acquire the object-relational metadata for your classes.

There are currently 4 available implementations:

  • Doctrine\ORM\Mapping\Driver\AnnotationDriver
  • Doctrine\ORM\Mapping\Driver\XmlDriver
  • Doctrine\ORM\Mapping\Driver\YamlDriver
  • Doctrine\ORM\Mapping\Driver\DriverChain

Throughout the most part of this manual the AnnotationDriver is used in the examples. For information on the usage of the XmlDriver or YamlDriver please refer to the dedicated chapters XML Mapping and YAML Mapping.

The annotation driver can be configured with a factory method on the Doctrine\ORM\Configuration:

<?php
$driverImpl = $config->newDefaultAnnotationDriver('/path/to/lib/MyProject/Entities');
$config->setMetadataDriverImpl($driverImpl);

The path information to the entities is required for the annotation driver, because otherwise mass-operations on all entities through the console could not work correctly. All of metadata drivers accept either a single directory as a string or an array of directories. With this feature a single driver can support multiple directories of Entities.

34.1.6. SQL Logger (*Optional*)

<?php
$config->setSQLLogger($logger);
$config->getSQLLogger();

Gets or sets the logger to use for logging all SQL statements executed by Doctrine. The logger class must implement the Doctrine\DBAL\Logging\SQLLogger interface. A simple default implementation that logs to the standard output using echo and var_dump can be found at Doctrine\DBAL\Logging\EchoSQLLogger.

34.1.7. Auto-generating Proxy Classes (*OPTIONAL*)

Proxy classes can either be generated manually through the Doctrine Console or automatically at runtime by Doctrine. The configuration option that controls this behavior is:

<?php
$config->setAutoGenerateProxyClasses($mode);

Possible values for $mode are:

  • Doctrine\Common\Proxy\AbstractProxyFactory::AUTOGENERATE_NEVER

Never autogenerate a proxy. You will need to generate the proxies manually, for this use the Doctrine Console like so:

$ ./doctrine orm:generate-proxies

When you do this in a development environment, be aware that you may get class/file not found errors if certain proxies are not yet generated. You may also get failing lazy-loads if new methods were added to the entity class that are not yet in the proxy class. In such a case, simply use the Doctrine Console to (re)generate the proxy classes.

  • Doctrine\Common\Proxy\AbstractProxyFactory::AUTOGENERATE_ALWAYS

Always generates a new proxy in every request and writes it to disk.

  • Doctrine\Common\Proxy\AbstractProxyFactory::AUTOGENERATE_FILE_NOT_EXISTS

Generate the proxy class when the proxy file does not exist. This strategy causes a file exists call whenever any proxy is used the first time in a request.

  • Doctrine\Common\Proxy\AbstractProxyFactory::AUTOGENERATE_EVAL

Generate the proxy classes and evaluate them on the fly via eval(), avoiding writing the proxies to disk. This strategy is only sane for development.

In a production environment, it is highly recommended to use AUTOGENERATE_NEVER to allow for optimal performances. The other options are interesting in development environment.

Before v2.4, setAutoGenerateProxyClasses would accept a boolean value. This is still possible, FALSE being equivalent to AUTOGENERATE_NEVER and TRUE to AUTOGENERATE_ALWAYS.

34.2. Development vs Production Configuration

You should code your Doctrine2 bootstrapping with two different runtime models in mind. There are some serious benefits of using APC or Memcache in production. In development however this will frequently give you fatal errors, when you change your entities and the cache still keeps the outdated metadata. That is why we recommend the ArrayCache for development.

Furthermore you should have the Auto-generating Proxy Classes option to true in development and to false in production. If this option is set to TRUE it can seriously hurt your script performance if several proxy classes are re-generated during script execution. Filesystem calls of that magnitude can even slower than all the database queries Doctrine issues. Additionally writing a proxy sets an exclusive file lock which can cause serious performance bottlenecks in systems with regular concurrent requests.

34.3. Connection Options

The $connectionOptions passed as the first argument to EntityManager::create() has to be either an array or an instance of Doctrine\DBAL\Connection. If an array is passed it is directly passed along to the DBAL Factory Doctrine\DBAL\DriverManager::getConnection(). The DBAL configuration is explained in the DBAL section.

34.4. Proxy Objects

A proxy object is an object that is put in place or used instead of the “real” object. A proxy object can add behavior to the object being proxied without that object being aware of it. In Doctrine 2, proxy objects are used to realize several features but mainly for transparent lazy-loading.

Proxy objects with their lazy-loading facilities help to keep the subset of objects that are already in memory connected to the rest of the objects. This is an essential property as without it there would always be fragile partial objects at the outer edges of your object graph.

Doctrine 2 implements a variant of the proxy pattern where it generates classes that extend your entity classes and adds lazy-loading capabilities to them. Doctrine can then give you an instance of such a proxy class whenever you request an object of the class being proxied. This happens in two situations:

34.4.1. Reference Proxies

The method EntityManager#getReference($entityName, $identifier) lets you obtain a reference to an entity for which the identifier is known, without loading that entity from the database. This is useful, for example, as a performance enhancement, when you want to establish an association to an entity for which you have the identifier. You could simply do this:

<?php
// $em instanceof EntityManager, $cart instanceof MyProject\Model\Cart
// $itemId comes from somewhere, probably a request parameter
$item = $em->getReference('MyProject\Model\Item', $itemId);
$cart->addItem($item);

Here, we added an Item to a Cart without loading the Item from the database. If you invoke any method on the Item instance, it would fully initialize its state transparently from the database. Here $item is actually an instance of the proxy class that was generated for the Item class but your code does not need to care. In fact it should not care. Proxy objects should be transparent to your code.

34.4.2. Association proxies

The second most important situation where Doctrine uses proxy objects is when querying for objects. Whenever you query for an object that has a single-valued association to another object that is configured LAZY, without joining that association in the same query, Doctrine puts proxy objects in place where normally the associated object would be. Just like other proxies it will transparently initialize itself on first access.

Note

Joining an association in a DQL or native query essentially means eager loading of that association in that query. This will override the ‘fetch’ option specified in the mapping for that association, but only for that query.

34.4.3. Generating Proxy classes

In a production environment, it is highly recommended to use AUTOGENERATE_NEVER to allow for optimal performances. However you will be required to generate the proxies manually using the Doctrine Console:

$ ./doctrine orm:generate-proxies

The other options are interesting in development environment:

  • AUTOGENERATE_ALWAYS will require you to create and configure a proxy directory. Proxies will be generated and written to file on each request, so any modification to your code will be acknowledged.
  • AUTOGENERATE_FILE_NOT_EXISTS will not overwrite an existing proxy file. If your code changes, you will need to regenerate the proxies manually.
  • AUTOGENERATE_EVAL will regenerate each proxy on each request, but without writing them to disk.

34.5. Autoloading Proxies

When you deserialize proxy objects from the session or any other storage it is necessary to have an autoloading mechanism in place for these classes. For implementation reasons Proxy class names are not PSR-0 compliant. This means that you have to register a special autoloader for these classes:

<?php
use Doctrine\ORM\Proxy\Autoloader;

$proxyDir = "/path/to/proxies";
$proxyNamespace = "MyProxies";

Autoloader::register($proxyDir, $proxyNamespace);

If you want to execute additional logic to intercept the proxy file not found state you can pass a closure as the third argument. It will be called with the arguments proxydir, namespace and className when the proxy file could not be found.

34.6. Multiple Metadata Sources

When using different components using Doctrine 2 you may end up with them using two different metadata drivers, for example XML and YAML. You can use the DriverChain Metadata implementations to aggregate these drivers based on namespaces:

<?php
use Doctrine\ORM\Mapping\Driver\DriverChain;

$chain = new DriverChain();
$chain->addDriver($xmlDriver, 'Doctrine\Tests\Models\Company');
$chain->addDriver($yamlDriver, 'Doctrine\Tests\ORM\Mapping');

Based on the namespace of the entity the loading of entities is delegated to the appropriate driver. The chain semantics come from the fact that the driver loops through all namespaces and matches the entity class name against the namespace using a strpos() === 0 call. This means you need to order the drivers correctly if sub-namespaces use different metadata driver implementations.

34.7. Default Repository (*OPTIONAL*)

Specifies the FQCN of a subclass of the EntityRepository. That will be available for all entities without a custom repository class.

<?php
$config->setDefaultRepositoryClassName($fqcn);
$config->getDefaultRepositoryClassName();

The default value is Doctrine\ORM\EntityRepository. Any repository class must be a subclass of EntityRepository otherwise you got an ORMException

34.8. Setting up the Console

Doctrine uses the Symfony Console component for generating the command line interface. You can take a look at the vendor/bin/doctrine.php script and the Doctrine\ORM\Tools\Console\ConsoleRunner command for inspiration how to setup the cli.

In general the required code looks like this:

<?php
$cli = new Application('Doctrine Command Line Interface', \Doctrine\ORM\Version::VERSION);
$cli->setCatchExceptions(true);
$cli->setHelperSet($helperSet);
Doctrine\ORM\Tools\Console\ConsoleRunner::addCommands($cli);
$cli->run();
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