Add transaction handling

src/Malocher/EventStore/Adapter/AdapterException.php

@@ -19,11 +19,22 @@ class AdapterException extends \Exception
     /**
      * Throw a configuration exception
      *
-     * @param $msg
+     * @param string $msg
      * @return AdapterException
      */
     public static function configurationException($msg)
     {
         return new self('[Adapter Configuration Error] ' . $msg . "\n");
     }
+
+    /**
+     * Throw an unsupported feature exception
+     * 
+     * @param string $msg
+     * @return AdapterException
+     */
+    public static function unsupportedFeatureException($msg)
+    {
+        return new self('[Adapter unsupported Feature] ' . $msg . "\n");
+    }
 }

src/Malocher/EventStore/Adapter/Doctrine/DoctrineDbalAdapter.php

@@ -12,6 +12,7 @@
 use Doctrine\DBAL\Connection;
 use Doctrine\DBAL\Schema\Schema;
 use Malocher\EventStore\Adapter\AdapterInterface;
+use Malocher\EventStore\Adapter\Feature\TransactionFeatureInterface;
 use Malocher\EventStore\Adapter\AdapterException;
 use Malocher\EventStore\EventSourcing\EventInterface;
 use Malocher\EventStore\EventSourcing\SnapshotEvent;
@@ -24,7 +25,7 @@
  * @author Manfred Weber <crafics@php.net>
  * @package Malocher\EventStore\Adapter\Doctrine
  */
-class DoctrineDbalAdapter implements AdapterInterface
+class DoctrineDbalAdapter implements AdapterInterface, TransactionFeatureInterface
 {
     /**
      * Doctrine DBAL connection
@@ -262,6 +263,21 @@ public function getCurrentSnapshotVersion($sourceFQCN, $sourceId)
 
         return 0;
     }
+
+    public function beginTransaction()
+    {
+        $this->conn->beginTransaction();
+    }
+
+    public function commit()
+    {
+        $this->conn->commit();
+    }
+
+    public function rollback()
+    {
+        $this->conn->rollBack();
+    }
 
     /**
      * Insert an event

src/Malocher/EventStore/Adapter/Feature/TransactionFeatureInterface.php

@@ -0,0 +1,23 @@
+<?php
+/*
+ * This file is part of the malocher/event-store package.
+ * (c) Manfred Weber <crafics@php.net> and Alexander Miertsch <kontakt@codeliner.ws>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace Malocher\EventStore\Adapter\Feature;
+
+/**
+ * Interface TransactionFeatureInterface
+ * 
+ * @author Alexander Miertsch <kontakt@codeliner.ws>
+ */
+interface TransactionFeatureInterface
+{
+    public function beginTransaction();
+
+    public function commit();
+
+    public function rollback();
+}

src/Malocher/EventStore/EventStore.php

@@ -9,6 +9,8 @@
 namespace Malocher\EventStore;
 
 use Malocher\EventStore\Adapter\AdapterInterface;
+use Malocher\EventStore\Adapter\Feature\TransactionFeatureInterface;
+use Malocher\EventStore\Adapter\AdapterException;
 use Malocher\EventStore\Configuration\Configuration;
 use Malocher\EventStore\EventSourcing\EventSourcedInterface;
 use Malocher\EventStore\EventSourcing\EventSourcedObjectFactory;
@@ -76,6 +78,16 @@ class EventStore
      * @var EventDispatcherInterface 
      */
     protected $eventDispatcher;
+
+    /**
+     * @var boolean
+     */
+    protected $inTransaction = false;
+
+    /**
+     * @var array
+     */
+    protected $pendingEvents = array();
 
     /**
      * Construct
@@ -180,7 +192,8 @@ public function save(EventSourcedInterface $eventSourcedObject)
                 );
             }
 
-            $this->events()->dispatch(PostPersistEvent::NAME, $postPersistEvent);
+            $this->addPendingEvent($postPersistEvent);
+            $this->tryDispatchPostPersistEvents();
         }
 
         $hash = $this->getIdentityHash(
@@ -232,6 +245,53 @@ public function clear()
         $this->identityMap = array();
     }
 
+    /**
+     * Begin transaction
+     * 
+     * @throws AdapterException If adapter does not support transactions
+     */
+    public function beginTransaction()
+    {
+        if (!$this->adapter instanceof TransactionFeatureInterface) {
+            throw AdapterException::unsupportedFeatureException('TransactionFeature');
+        }
+
+        $this->inTransaction = true;
+        $this->adapter->beginTransaction();
+    }
+
+    /**
+     * Commit transaction
+     * 
+     * @throws AdapterException If adapter does not support transactions
+     */
+    public function commit()
+    {
+        if (!$this->adapter instanceof TransactionFeatureInterface) {
+            throw AdapterException::unsupportedFeatureException('TransactionFeature');
+        }
+
+        $this->adapter->commit();
+        $this->inTransaction = false;
+        $this->tryDispatchPostPersistEvents();
+    }
+
+    /**
+     * Rollback transaction
+     * 
+     * @throws AdapterException If adapter does not support transactions
+     */
+    public function rollback()
+    {
+        if (!$this->adapter instanceof TransactionFeatureInterface) {
+            throw AdapterException::unsupportedFeatureException('TransactionFeature');
+        }
+
+        $this->adapter->rollback();
+        $this->inTransaction = false;
+        $this->pendingEvents = array();
+    }
+
     /**
      * Get hash to identify EventSourcedObject in the IdentityMap
      * 
@@ -244,4 +304,28 @@ protected function getIdentityHash($sourceFQCN, $sourceId)
     {        
         return $sourceFQCN . '::' . $sourceId;
     }
+
+    /**
+     * @param PostPersistEvent $event
+     */
+    protected function addPendingEvent(PostPersistEvent $event)
+    {
+        $this->pendingEvents[] = $event;
+    }
+
+
+    /**
+     * Events are only dispatched if the event store has no running transaction
+     */
+    protected function tryDispatchPostPersistEvents()
+    {
+        if (!$this->inTransaction) {
+            $events = $this->pendingEvents;
+            $this->pendingEvents = array();
+
+            foreach ($events as $event) {
+                $this->events()->dispatch(PostPersistEvent::NAME, $event);
+            }
+        }
+    }
 }

tests/Malocher/EventStoreTest/Coverage/EventStore/EventStoreTest.php

@@ -157,4 +157,65 @@ function(PostPersistEvent $e) use (&$persistedEventList) {
 
         $this->assertEquals($check, $persistedEventList);
     }
+
+    public function testBeginTransactionAndCommit()
+    {
+        $this->eventStore->beginTransaction();
+
+        $factory = new EventSourcedObjectFactory();
+        $user = $factory->create('Malocher\EventStoreTest\Coverage\Mock\User', '1');
+
+        $user->changeName('Malocher');
+        $user->changeEmail('my.email@getmalocher.org');
+
+        $persistedEventList = array();        
+
+        $this->eventStore->events()->addListener(
+            PostPersistEvent::NAME, 
+            function(PostPersistEvent $e) use (&$persistedEventList) {
+                foreach ($e->getPersistedEvents() as $persistedEvent) {
+                    $persistedEventList[] = get_class($persistedEvent);
+                }
+            }
+        );
+
+        $this->eventStore->save($user);
+
+        $this->eventStore->commit();
+
+        $check = array(
+            'Malocher\EventStoreTest\Coverage\Mock\Event\UserNameChangedEvent',
+            'Malocher\EventStoreTest\Coverage\Mock\Event\UserEmailChangedEvent'
+        );
+
+        $this->assertEquals($check, $persistedEventList);
+    }
+
+    public function testBeginTransactionAndRollback()
+    {
+        $this->eventStore->beginTransaction();
+
+        $factory = new EventSourcedObjectFactory();
+        $user = $factory->create('Malocher\EventStoreTest\Coverage\Mock\User', '1');
+
+        $user->changeName('Malocher');
+        $user->changeEmail('my.email@getmalocher.org');
+
+        $persistedEventList = array();        
+
+        $this->eventStore->events()->addListener(
+            PostPersistEvent::NAME, 
+            function(PostPersistEvent $e) use (&$persistedEventList) {
+                foreach ($e->getPersistedEvents() as $persistedEvent) {
+                    $persistedEventList[] = get_class($persistedEvent);
+                }
+            }
+        );
+
+        $this->eventStore->save($user);
+
+        $this->eventStore->rollback();
+
+        $this->assertEmpty($persistedEventList);
+    }
 }