Zend Framework 2 ‘Cheat Sheet’ : Service Manager

The Service Locator design pattern is implemented by the ServiceManager. The Service Locator is a service/object locator, tasked with retrieving other objects.

Get the SM :
1. Inside Controller

$serviceLocator = $this->getServiceLocator();

2. Inside Module.php

namespace YourModule\Service;

use Zend\Mvc\MvcEvent;

class Module
{
    public function onBootstrap(MvcEvent $e)
    {
        $sm = $e->getApplication()->getServiceManager();
    }
}

3. Inside Controller Plugin

$serviceLocator = $this->getController()->getServiceLocator();

Types of Services
The registered name of service is not case sensitive. There are the type of services :
a. invokables : an array of service name/class name pairs. The class name should be class that may be directly instantiated without any constructor arguments
for ex :

//YourModule/config/module.config.php
return array(
    'controllers'=>array(
        'invokables' => array(
            'SanUser\Controller\User' => 'SanUser\Controller\UserController'
        ),
    ),
);

b. abstract_factories : Unknown Services ( The “Limbo” if ServiceManager failed to search in registered services)

//YourModule/src/YourModule/Service/CommonControlAppAbstractFactory.php
namespace YourModule\Service;

use Zend\ServiceManager\AbstractFactoryInterface;
use Zend\ServiceManager\ServiceLocatorInterface;

class CommonControlAppAbstractFactory implements AbstractFactoryInterface
{
    public function canCreateServiceWithName(ServiceLocatorInterface $locator, $name, $requestedName)
    {
        if (class_exists($requestedName.'Controller')){
            return true;
        }

        return false;
    }

    public function createServiceWithName(ServiceLocatorInterface $locator, $name, $requestedName)
    {
        $class = $requestedName.'Controller';
        return new $class;
    }
}

Then, register in SM :

//YourModule/config/module.config.php
return array(
    'controllers'=> array(
	    'abstract_factories' => array(
		'YourModule\Service\CommonControlAppAbstractFactory',
	    ),
	);
    ),
);

In this case, if SM could not find controllers in invokables, the SM will turn to it whenever canCreateServiceWithName return true; ( controllers is service that called automatically by mvc stack )
What if you want other service ? This is it :

namespace YourModule\Service;

use Zend\ServiceManager\AbstractFactoryInterface;
use Zend\ServiceManager\ServiceLocatorInterface;

class CommonModelTableAbstractFactory implements AbstractFactoryInterface
{
    public function canCreateServiceWithName(ServiceLocatorInterface $locator, $name, $requestedName)
    {
        return (substr($requestedName, -5) === 'Table');
    }

    public function createServiceWithName(ServiceLocatorInterface $locator, $name, $requestedName)
    {
        $db = $locator->get('Zend\Db\Adapter\Adapter');
        $tablemodel = new $requestedName;
        $tablemodel->setDbAdapter($db);
        
        return $tablemodel;
    }
}

You want if you call un-registered table model, you automatically create service with this abstract factory whenever last 5 chars of the service called = ‘Table’. Register this abstract factory under service_manager key :

//YourModule/config/module.config.php
return array(
    'service_manager'=> array(
	    'abstract_factories' => array(
		'YourModule\Service\CommonModelTableAbstractFactory',
	    ),
	);
    ),
);

Note for abstract_factories : Being explicit is more secure and reliable. You should not forgot to register service you write into ServiceManager.

c. factories : an array of service name/factory class name pairs.
c.1. If you are using PHP configuration files, you may provide any PHP callable as the factory.

//YourModule/config/module.config.php
return array(
    'service_manager'=>array(
        'factories' => array(
            'MyTable' => function ($sm) {
                $db = $sm->get('Zend\Db\Adapter\DbAdapter');
                $table = new \YourModule\Model\MyTableModel();
                $table->setDbAdapter($db);
            },
        ),
    ),
);

c.2. by implementing Zend\ServiceManager\FactoryInterface by create a factory first :

namespace YourModule\Service;

use Zend\ServiceManager\FactoryInterface;
use Zend\ServiceManager\ServiceLocatorInterface;

class MyTableFactory implements FactoryInterface
{
    public function createService(ServiceLocatorInterface $serviceLocator)
    {
        $db = $serviceLocator->get('Zend\Db\Adapter\DbAdapter');
        $table = new \YourModule\Model\MyTableModel();
        $table->setDbAdapter($db);

        return $table;
    }
}

And the factories registered just like the following :

//YourModule/config/module.config.php
return array(
    'service_manager'=>array(
        'factories' => array(
            'MyTable' => 'YourModule\Service\MyTableFactory'
        ),
    ),
);

d. aliases : which should be an associative array of alias name/target name pairs (where the target name may also be an alias).

//YourModule/config/module.config.php
return array(
    'service_manager'=>array(
        'factories' => array(
            'MyTable' => 'YourModule\Service\MyTableFactory'
        ),
        'aliases' => array(
            'YourModule\Model\MyTable' => 'MyTable',
        ),
    ),
);

e. shared :an array of service name/boolean pairs, indicating whether or not a service should be shared. By default, the ServiceManager assumes all services are shared, but you may specify a boolean false value here to indicate a new instance should be returned.

//YourModule/config/module.config.php
return array(
    'service_manager'=>array(
        'factories' => array(
            'MyTable' => 'YourModule\Service\MyTableFactory'
        ),
        'shared' => array(
            // Usually, you'll only indicate services that should _NOT_ be
            // shared -- i.e., ones where you want a different instance
            // every time.
            'MyTable' => false,
        ),
    ),
);

f. services : an array of service name/object pairs. Clearly, this will only work with PHP configuration.

//YourModule/config/module.config.php
return array(
    'service_manager'=>array(
        'services' => array(
            // Keys are the service names
            // Values are objects
            'Auth' => new YourModule\Authentication\AuthenticationService(),
        ),
    ),
);

g. initializers
It initialize the service whenever service created. It can reduce the redundance the injections to services.

//YourModule/config/module.config.php
return array(
    'service_manager'=>array(
        'initializers' => array(
	    function ($instance, $sm) {
		if ($instance instanceof \Zend\Db\Adapter\AdapterAwareInterface) {
		    $instance->setDbAdapter($sm->get('Zend\Db\Adapter\Adapter'));
		}
	    }
	),
    ),
);

And you should not to inject Adapter manually in the Table Class :

namespace YourModule\Model;

use Zend\Db\TableGateway\AbstractTableGateway;
use Zend\Db\Adapter\AdapterAwareInterface;
use Zend\Db\Adapter\Adapter;

class UserTable extends AbstractTableGateway
    implements AdapterAwareInterface
{
    protected $table = 'zf2_users';

    public function setDbAdapter(Adapter $adapter)
    {
        $this->adapter = $adapter;
        $this->initialize();
    }
}

Just invoke at service_manager :

//YourModule/config/module.config.php
return array(
    'service_manager'=>array(
        'initializers' => array(
	    function ($instance, $sm) {
		if ($instance instanceof \Zend\Db\Adapter\AdapterAwareInterface) {
		    $instance->setDbAdapter($sm->get('Zend\Db\Adapter\Adapter'));
		}
	    }
	),
        'invokables' => array(
            'YourModule\Model\UserTable' => 'YourModule\Model\UserTable'
        )
    ),
);

h. allow_override
Override your existing Services.

//YourModule/config/module.config.php
return array(
    'service_manager'=>array(
        'factories' => array(
            'MyService' => 'YourModule\Service\MyServiceFactory'
        ),
        'allow_override' => array(
            'MyService' => true,
        ),
    ),
);

The top level configuration keys

Manager	Key name in configuration array	Method name in Module.php
ServiceManager	service_manager	getServiceConfig()
ViewHelperManager	view_helpers	getViewHelperConfig()
ControllerPluginManager	controller_plugins	getControllerPluginConfig()
ControllerLoader	controllers	getControllerConfig()

Sample Code in Module.php :

class Module
{
    //for 'service_manager'
    public function getServiceConfig()
    {
        return array(
            'invokables' => array( /* see Types of Services */  ),
            'factories' => array( /* see Types of Services */ ),
            'abstract_factories' => array( /* see Types of Services */ ),
            'aliases' => array( /* see Types of Services */ ),
            'services' => array( /* see Types of Services */ ),
            'initializers' => array( /* see Types of Services */ ),
            'shared' => array(/* see Types of Services */),
        );
    }

    //for 'controllers' -> it automatically composed by mvc stack
    //no need to call by your hand ( get('...') );
    public function getControllerConfig()
    {
        return array(
            /* looks like above code */
        );
    }

    //for 'controller_plugins'
    public function getControllerPluginConfig()
    {
        return array(
            /* looks like above code */
        );
    }

    //for 'view_helpers' call in view by $this->nameViewHelperRegistered()->dosomething()
    public function getViewHelperConfig()
    {
        return array(
            /* looks like above code */
        );
    }
}

For ZF 2.1 ( still in dev branch, the keys added with FormElementManager )

Manager	Key name in configuration array	Method name in Module.php
FormElementManager	form_elements	getFormElementConfig()

For what have to do to create a Controller pLugin , see : empirio’s post about creating Controller pLugin in ZF2. For what have to do to create a View Helper , see : my post about creating view helper or EvanDotPro’s post.

Hope this post helpful ;). Happy new Year!

References :
1. http://zf2.readthedocs.org/en/latest/modules/zend.service-manager.intro.html
2. http://akrabat.com/zend-framework-2/zendservicemanager-configuration-keys/
3. http://juriansluiman.nl/en/article/120/using-zend-framework-service-managers-in-your-application
4. http://blog.evan.pro/creating-a-simple-view-helper-in-zend-framework-2
5. http://lab.empirio.no/custom-controller-plugin-in-zf2.html