zendframework · weierophinney · Apr 15, 2013 · Mar 25, 2013 · Mar 26, 2013 · Mar 26, 2013
diff --git a/library/Zend/ServiceManager/Config.php b/library/Zend/ServiceManager/Config.php
@@ -106,6 +106,17 @@ public function getShared()
         return (isset($this->config['shared'])) ? $this->config['shared'] : array();
     }
 
+    /**
+     * Get the delegator services map, with keys being the services acting as delegates,
+     * and values being the delegator factories names
+     *
+     * @return array
+     */
+    public function getDelegators()
+    {
+        return (isset($this->config['delegators'])) ? $this->config['delegators'] : array();
+    }
+
     /**
      * Configure service manager
      *
@@ -145,5 +156,11 @@ public function configureServiceManager(ServiceManager $serviceManager)
         foreach ($this->getShared() as $name => $isShared) {
             $serviceManager->setShared($name, $isShared);
         }
+
+        foreach ($this->getDelegators() as $originalServiceName => $delegators) {
+            foreach ($delegators as $delegator) {
+                $serviceManager->addDelegator($originalServiceName, $delegator);
+            }
+        }
     }
 }
diff --git a/library/Zend/ServiceManager/DelegatorFactoryInterface.php b/library/Zend/ServiceManager/DelegatorFactoryInterface.php
@@ -0,0 +1,28 @@
+<?php
+/**
+ * Zend Framework (http://framework.zend.com/)
+ *
+ * @link      http://github.com/zendframework/zf2 for the canonical source repository
+ * @copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd New BSD License
+ */
+
+namespace Zend\ServiceManager;
+
+/**
+ * Interface for factories that can create delegators for services
+ */
+interface DelegatorFactoryInterface
+{
+    /**
+     * A factory that creates delegators of a given service
+     *
+     * @param ServiceLocatorInterface $serviceLocator the service locator which requested the service
+     * @param string                  $name           the normalized service name
+     * @param string                  $requestedName  the requested service name
+     * @param callable                $callback       the callback that is responsible for creating the service
+     *
+     * @return mixed
+     */
+    public function createDelegatorWithName(ServiceLocatorInterface $serviceLocator, $name, $requestedName, $callback);
+}
diff --git a/library/Zend/ServiceManager/ServiceManager.php b/library/Zend/ServiceManager/ServiceManager.php
@@ -48,6 +48,11 @@ class ServiceManager implements ServiceLocatorInterface
      */
     protected $abstractFactories = array();
 
+    /**
+     * @var array[]
+     */
+    protected $delegators = array();
+
     /**
      * @var array
      */
@@ -311,6 +316,25 @@ public function addAbstractFactory($factory, $topOfStack = true)
         return $this;
     }
 
+    /**
+     * Sets the given service name as to be handled by a delegator factory
+     *
+     * @param  string $serviceName          name of the service being the delegate
+     * @param  string $delegatorFactoryName name of the service being the delegator factory
+     *
+     * @return ServiceManager
+     */
+    public function addDelegator($serviceName, $delegatorFactoryName)
+    {
+        if (!isset($this->delegators[$this->canonicalizeName($serviceName)])) {
+            $this->delegators[$this->canonicalizeName($serviceName)] = array();
+        }
+
+        $this->delegators[$this->canonicalizeName($serviceName)][] = $delegatorFactoryName;
+
+        return $this;
+    }
+
     /**
      * Add initializer
      *
@@ -475,17 +499,14 @@ public function get($name, $usePeeringServiceManagers = true)
     }
 
     /**
-     * Create an instance
+     * Create an instance of the requested service
      *
      * @param  string|array $name
+     *
      * @return bool|object
-     * @throws Exception\ServiceNotFoundException
-     * @throws Exception\ServiceNotCreatedException
      */
     public function create($name)
     {
-        $instance = false;
-
         if (is_array($name)) {
             list($cName, $rName) = $name;
         } else {
@@ -499,6 +520,67 @@ public function create($name)
             }
         }
 
+        if (isset($this->delegators[$cName])) {
+            $serviceManager       = $this;
+            $additionalDelegators = count($this->delegators[$cName]) - 1;
+            $creationCallback     = function () use ($serviceManager, $rName, $cName) {
+                return $serviceManager->doCreate($rName, $cName);
+            };
+
+            for ($i = 0; $i < $additionalDelegators; $i += 1) {
+                $creationCallback = $this->createDelegatorCallback(
+                    $this->delegators[$cName][$i],
+                    $rName,
+                    $cName,
+                    $creationCallback
+                );
+            }
+
+            /* @var $delegatorFactory DelegatorFactoryInterface */
+            $delegatorFactory = $this->get($this->delegators[$cName][$i]);
+
+            return $delegatorFactory->createDelegatorWithName($this, $cName, $rName, $creationCallback);
+        }
+
+        return $this->doCreate($rName, $cName);
+    }
+
+    /**
+     * Creates a callback that uses a delegator to create a service
+     *
+     * @param string   $delegatorFactoryName name of the delegator factory service
+     * @param string   $rName                requested service name
+     * @param string   $cName                canonical service name
+     * @param callable $creationCallback     callback that is responsible for instantiating the service
+     *
+     * @return callable
+     */
+    private function createDelegatorCallback($delegatorFactoryName, $rName, $cName, $creationCallback)
+    {
+        $serviceManager  = $this;
+
+        return function () use ($serviceManager, $delegatorFactoryName, $rName, $cName, $creationCallback) {
+            /* @var $delegatorFactory DelegatorFactoryInterface */
+            $delegatorFactory = $serviceManager->get($delegatorFactoryName);
+
+            return $delegatorFactory->createDelegatorWithName($serviceManager, $cName, $rName, $creationCallback);
+        };
+    }
+
+    /**
+     * Actually creates the service
+     *
+     * @param string $rName real service name
+     * @param string $cName canonicalized service name
+     *
+     * @return bool|mixed|null|object
+     * @throws Exception\ServiceNotFoundException
+     *
+     * @internal this method is internal because of PHP 5.3 compatibility - do not explicitly use it
+     */
+    public function doCreate($rName, $cName)
+    {
+        $instance = false;
 
         if (isset($this->factories[$cName])) {
             $instance = $this->createFromFactory($cName, $rName);

diff --git a/tests/ZendTest/ServiceManager/ServiceManagerTest.php b/tests/ZendTest/ServiceManager/ServiceManagerTest.php
@@ -18,6 +18,7 @@
 use Zend\ServiceManager\Config;
 
 use ZendTest\ServiceManager\TestAsset\FooCounterAbstractFactory;
+use ZendTest\ServiceManager\TestAsset\MockSelfReturningDelegatorFactory;
 
 class ServiceManagerTest extends \PHPUnit_Framework_TestCase
 {
@@ -728,4 +729,62 @@ public function testRetrieveServiceFromPeeringServiceManagerIfretrieveFromPeerin
         $this->assertEquals($serviceManagerChild->get($foo1), $boo2);
         $this->assertEquals($this->serviceManager->get($foo1), $boo2);
     }
+
+    /**
+     * @covers Zend\ServiceManager\ServiceManager::create
+     * @covers Zend\ServiceManager\ServiceManager::createDelegatorCallback
+     * @covers Zend\ServiceManager\ServiceManager::addDelegator
+     */
+    public function testUsesDelegatorWhenAvailable()
+    {
+        $delegator = $this->getMock('Zend\\ServiceManager\\DelegatorFactoryInterface');
+
+        $this->serviceManager->setService('foo-delegator', $delegator);
+        $this->serviceManager->addDelegator('foo-service', 'foo-delegator');
+        $this->serviceManager->setInvokableClass('foo-service', 'stdClass');
+
+        $delegator
+            ->expects($this->once())
+            ->method('createDelegatorWithName')
+            ->with(
+                $this->serviceManager,
+                'fooservice',
+                'foo-service',
+                $this->callback(function ($callback) {
+                    if (!is_callable($callback)) {
+                        return false;
+                    }
+
+                    $service = call_user_func($callback);
+
+                    return $service instanceof \stdClass;
+                })
+            )
+            ->will($this->returnValue($delegator));
+
+        $this->assertSame($delegator, $this->serviceManager->create('foo-service'));
+    }
+
+    /**
+     * @covers Zend\ServiceManager\ServiceManager::create
+     * @covers Zend\ServiceManager\ServiceManager::createDelegatorCallback
+     * @covers Zend\ServiceManager\ServiceManager::addDelegator
+     */
+    public function testUsesMultipleDelegates()
+    {
+        $fooDelegator = new MockSelfReturningDelegatorFactory();
+        $barDelegator = new MockSelfReturningDelegatorFactory();
+
+        $this->serviceManager->setService('foo-delegate', $fooDelegator);
+        $this->serviceManager->setService('bar-delegate', $barDelegator);
+        $this->serviceManager->addDelegator('foo-service', 'foo-delegate');
+        $this->serviceManager->addDelegator('foo-service', 'bar-delegate');
+        $this->serviceManager->setInvokableClass('foo-service', 'stdClass');
+
+        $this->assertSame($barDelegator, $this->serviceManager->create('foo-service'));
+        $this->assertCount(1, $barDelegator->instances);
+        $this->assertCount(1, $fooDelegator->instances);
+        $this->assertInstanceOf('stdClass', array_shift($fooDelegator->instances));
+        $this->assertSame($fooDelegator, array_shift($barDelegator->instances));
+    }
 }
diff --git a/tests/ZendTest/ServiceManager/TestAsset/MockSelfReturningDelegatorFactory.php b/tests/ZendTest/ServiceManager/TestAsset/MockSelfReturningDelegatorFactory.php
@@ -0,0 +1,35 @@
+<?php
+/**
+ * Zend Framework (http://framework.zend.com/)
+ *
+ * @link      http://github.com/zendframework/zf2 for the canonical source repository
+ * @copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd New BSD License
+ * @package   Zend_ServiceManager
+ */
+
+namespace ZendTest\ServiceManager\TestAsset;
+
+use Zend\ServiceManager\DelegatorFactoryInterface;
+use Zend\ServiceManager\ServiceLocatorInterface;
+
+/**
+ * Mock factory that logs delegated service instances and returns itself instead of the original service
+ */
+class MockSelfReturningDelegatorFactory implements DelegatorFactoryInterface
+{
+    /**
+     * @var mixed[]
+     */
+    public $instances = array();
+
+    /**
+     * {@inheritDoc}
+     */
+    public function createDelegatorWithName(ServiceLocatorInterface $serviceLocator, $name, $requestedName, $callback)
+    {
+        $this->instances[] = call_user_func($callback);
+
+        return $this;
+    }
+}