Reference
Plugin Managers
It can be useful to compose a plugin manager from which you can retrieve
hydrators; in fact, Zend\Hydrator\DelegatingHydrator
does exactly that!
With such a manager, you can retrieve instances using short names, or instances
that have dependencies on other services, without needing to know the details of
how that works.
Examples of Hydrator plugin managers in real-world scenarios include:
HydratorPluginManagerInterface
We provide two plugin manager implementations. Essentially, they only need to implement the PSR-11 ContainerInterface, but plugin managers in current versions of zend-servicemanager only implement it indirectly via the container-interop project.
As such, we ship Zend\Hydrator\HydratorPluginManagerInterface
, which simply
extends the PSR-11 Psr\Container\ContainerInterface
. Each of our
implementations implement it.
HydratorPluginManager
If you have used zend-hydrator prior to version 3, you are likely already
familiar with this class, as it has been the implementation we have shipped from
initial versions. The HydratorPluginManager
extends the zend-servicemanager
AbstractPluginManager
, and has the following behaviors:
- It will only return
Zend\Hydrator\HydratorInterface
instances. - It defines short-name aliases for all shipped hydrators (the class name minus the namespace), in a variety of casing combinations.
- All but the
DelegatingHydrator
are defined as invokable services (meaning they can be instantiated without any constructor arguments). - The
DelegatingHydrator
is configured as a factory-based service, mapping to theZend\Hydrator\DelegatingHydratorFactory
. - No services are shared; a new instance is created each time you call
get()
.
HydratorPluginManagerFactory
Zend\Hydrator\HydratorPluginManager
is mapped to the factory
Zend\Hydrator\HydratorPluginManagerFactory
when wired to the dependency
injection container.
The factory will look for the config
service, and use the hydrators
configuration key to seed it with additional services. This configuration key
should map to an array that follows standard zend-servicemanager configuration.
StandaloneHydratorPluginManager
Zend\Hydrator\StandaloneHydratorPluginManager
provides an implementation that
has no dependencies on other libraries. It can only load the hydrators shipped
with zend-hydrator.
StandardHydratorPluginManagerFactory
Zend\Hydrator\StandardHydratorPluginManager
is mapped to the factory
Zend\Hydrator\StandardHydratorPluginManagerFactory
when wired to the dependency
injection container.
HydratorManager alias
Zend\Hydrator\ConfigManager
defines an alias service, HydratorManager
. That
service will point to Zend\Hydrator\HydratorPluginManager
if
zend-servicemanager is installed, and Zend\Hydrator\StandaloneHydratorPluginManager
otherwise.
Custom plugin managers
If you do not want to use zend-servicemanager, but want a plugin manager that is
customizable, or at least capable of loading the hydrators you have defined for
your application, you should write a custom implementation of
Zend\Hydrator\HydratorPluginManagerInterface
, and wire it to the
HydratorManager
service, and/or one of the existing service names.
As an example, if you want a configurable solution that uses factories, and want those factories capable of pulling application-level dependencies, you might do something like the following:
// In src/YourApplication/CustomHydratorPluginManager.php:
namespace YourApplication;
use Psr\Container\NotFoundExceptionInterface;
use Psr\Container\ContainerInterface;
use RuntimeException;
use Zend\Hydrator\HydratorInterface;
use Zend\Hydrator\HydratorPluginManagerInterface;
use Zend\Hydrator\StandaloneHydratorPluginManager;
class CustomHydratorPluginManager implements HydratorPluginManagerInterface
{
/** @var ContainerInterface */
private $appContainer;
/** @var StandaloneHydratorPluginManager */
private $defaults;
/** @var array<string, string|callable> */
private $factories = [];
public function __construct(ContainerInterface $appContainer)
{
$this->appContainer = $appContainer;
$this->defaults = new StandaloneHydratorPluginManager();
}
/**
* {@inheritDoc}
*/
public function get($id) : HydratorInterface
{
if (! isset($this->factories[$id]) && ! $this->defaults->has($id)) {
$message = sprintf('Hydrator service %s not found', $id);
throw new class($message) extends RuntimeException implements NotFoundExceptionInterface {};
}
// Default was requested; fallback to standalone container
if (! isset($this->factories[$id])) {
return $this->defaults->get($id);
}
$factory = $this->factories[$id];
if (is_string($factory)) {
$this->factories[$id] = $factory = new $factory();
}
return $factory($this->appContainer, $id);
}
public function has($id) : bool
{
return isset($this->factories[$id]) || $this->defaults->has($id);
}
public function setFactoryClass(string $name, string $factory) : void
{
$this->factories[$name] = $factory;
}
public function setFactory(string $name, callable $factory) : void
{
$this->factories[$name] = $factory;
}
}
// In src/YourApplication/CustomHydratorPluginManagerFactory.php:
namespace YourApplication;
use Psr\Container\ContainerInterface;
class CustomHydratorPluginManagerFactory
{
public function __invoke(ContainerInterface $container) : CustomHydratorPluginManager
{
$config = $container->has('config') ? $container->get('config') : [];
$config = $config['hydrators']['factories'] ?? [];
$manager = new CustomHydratorPluginManager($this);
if ([] !== $config) {
$this->configureManager($manager, $config);
}
return $manager;
}
/**
* @param array<string, string|callable> $config
*/
private function configureManager(CustomHydratorPluginManager $manager, array $config) : void
{
foreach ($config as $name => $factory) {
is_string($factory)
? $manager->setFactoryClass($name, $factory)
: $manager->setFactory($name, $factory);
}
}
}
// in config/autoload/hydrators.global.php or similar:
return [
'dependencies' => [
'aliases' => [
'HydratorManager' => \YourApplication\CustomHydratorPluginManager::class,
],
'factories' => [
\YourApplication\CustomHydratorPluginManager::class => \YourApplication\CustomHydratorPluginManagerFactory::class
],
],
'hydrators' => [
'factories' => [
\Blog\PostHydrator::class => \Blog\PostHydratorFactory::class,
\News\ItemHydrator::class => \News\ItemHydratorFactory::class,
// etc.
],
],
];
Found a mistake or want to contribute to the documentation? Edit this page on GitHub!