Version22

The main thing I did in this commit was to add an event dispatcher. I
throw a domain event in my model when entering a room and needed the
dispatcher in place to support that.

As I am using Symfony it made sense to me to use the Symfony event
dispatcher. However, it is a bit of a pain because it expects to have a
name and to be `Symfony\Component\EventDispatcher\Event`, as I was
trying to follow the clean architecture and have no outer dependencies I
didn't want to have my event extend
`Symfony\Component\EventDispatcher\Event`. Therefore, I needed to create
an adapter. Going back to the Raspberry Pi analogy made in a previous
version. I needed a serial to usb adapter, or something like that.

I also wanted to use my own Dispatcher interface, because what if I
wanted to stop using the Symfony dispatcher and replace it with
something else? I want to be able to continue using the same interface
but just add a new adapter and change my DI. You can see how I achieved
this from the code within this commit.

Finally, I added a `HandlerInterface` so that I can swap out handlers
using DI should I need to.

spec/Jenko/House/Factory/HomeAloneHouseFactorySpec.php

@@ -10,7 +10,7 @@ class HomeAloneHouseFactorySpec extends ObjectBehavior
     function it_is_initializable()
     {
         $this->shouldHaveType('Jenko\House\Factory\HomeAloneHouseFactory');
-        $this->shouldHaveType('Jenko\House\Factory\HouseFactory');
+        $this->shouldHaveType('Jenko\House\Factory\HouseFactoryInterface');
     }
 
     function it_should_return_a_house()

spec/Jenko/House/Handler/EnterRoomHandlerSpec.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace spec\Jenko\House\Handler;
+
+use Jenko\House\Command\EnterRoomCommand;
+use Jenko\House\Event\EventDispatcherInterface;
+use Jenko\House\Factory\HomeAloneHouseFactory;
+use PhpSpec\ObjectBehavior;
+use Prophecy\Argument;
+
+class EnterRoomHandlerSpec extends ObjectBehavior
+{
+    function let(EventDispatcherInterface $dispatcher)
+    {
+        $this->beConstructedWith($dispatcher);
+    }
+
+    function it_is_initializable()
+    {
+        $this->shouldHaveType('Jenko\House\Handler\EnterRoomHandler');
+    }
+
+    function it_dispatches_events(EventDispatcherInterface $dispatcher)
+    {
+        $house = HomeAloneHouseFactory::getHouse();
+        $house->enterRoom('hallway');
+
+        $command = new EnterRoomCommand();
+        $command->room = 'kitchen';
+
+        $dispatcher->dispatch(Argument::any())->shouldBeCalled();
+        $this->handle($command);
+    }
+}

spec/Jenko/House/Handler/ExitRoomHandlerSpec.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace spec\Jenko\House\Handler;
+
+use Jenko\House\Command\ExitRoomCommand;
+use Jenko\House\Event\EventDispatcherInterface;
+use Jenko\House\Factory\HomeAloneHouseFactory;
+use PhpSpec\ObjectBehavior;
+use Prophecy\Argument;
+
+class ExitRoomHandlerSpec extends ObjectBehavior
+{
+    function let(EventDispatcherInterface $dispatcher)
+    {
+        $this->beConstructedWith($dispatcher);
+    }
+
+    function it_is_initializable()
+    {
+        $this->shouldHaveType('Jenko\House\Handler\ExitRoomHandler');
+    }
+
+    function it_dispatches_events(EventDispatcherInterface $dispatcher)
+    {
+        $house = HomeAloneHouseFactory::getHouse();
+        $house->enterRoom('hallway');
+
+        $command = new ExitRoomCommand();
+        $command->room = 'kitchen';
+
+        $dispatcher->dispatch(Argument::any())->shouldBeCalled();
+        $this->handle($command);
+    }
+}

src/Jenko/House/Adapter/SymfonyEventAdapter.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Jenko\House\Adapter;
+
+use Symfony\Component\EventDispatcher\Event;
+
+class SymfonyEventAdapter extends Event
+{
+
+}

src/Jenko/House/Adapter/SymfonyEventDispatcherAdapter.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace Jenko\House\Adapter;
+
+use Jenko\House\Event\EventDispatcherInterface as LocalEventDispatcherInterface;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+
+class SymfonyEventDispatcherAdapter implements LocalEventDispatcherInterface
+{
+    /**
+     * @var EventDispatcherInterface
+     */
+    protected $dispatcher;
+    /**
+     * @param EventDispatcherInterface $dispatcher
+     */
+    public function __construct(EventDispatcherInterface $dispatcher)
+    {
+        $this->dispatcher = $dispatcher;
+    }
+    /**
+     * {@inheritdoc}
+     */
+    public function dispatch(array $events)
+    {
+        foreach ($events as $event) {
+            $this->dispatcher->dispatch($event::NAME, $event);
+        }
+    }
+}

src/Jenko/House/Event/EnteredRoomEvent.php

@@ -2,8 +2,12 @@
 
 namespace Jenko\House\Event;
 
-class EnteredRoomEvent
+use Jenko\House\Adapter\SymfonyEventAdapter;
+
+class EnteredRoomEvent extends SymfonyEventAdapter
 {
+    const NAME = 'house.room-entered';
+
     public $roomName;
     public $enteredOn;
 

src/Jenko/House/Event/EventDispatcherInterface.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Jenko\House\Event;
+
+interface EventDispatcherInterface
+{
+    /**
+     * @param array $events
+     * @return mixed
+     */
+    public function dispatch(array $events);
+}

src/Jenko/House/Event/EventGenerator.php

@@ -0,0 +1,32 @@
+<?php
+
+namespace Jenko\House\Event;
+
+trait EventGenerator
+{
+    /**
+     * @var array
+     */
+    protected $pendingEvents = [];
+
+    /**
+     * Raise a new event
+     *
+     * @param $event
+     */
+    public function raiseEvent($event)
+    {
+        $this->pendingEvents[] = $event;
+    }
+
+    /**
+     * @return array
+     */
+    public function releaseEvents()
+    {
+        $events = $this->pendingEvents;
+        $this->pendingEvents = [];
+
+        return $events;
+    }
+}

src/Jenko/House/Factory/HomeAloneHouseFactory.php

@@ -11,7 +11,7 @@
  * Note: Usually you would have some kind of persistence mechanism. However, in our case a static factory (essentially
  * a singleton) is fine, as the house itself won't change.
  */
-final class HomeAloneHouseFactory implements HouseFactory
+final class HomeAloneHouseFactory implements HouseFactoryInterface
 {
     /**
      * @var House $house

src/Jenko/House/Factory/HouseFactory.php → src/Jenko/House/Factory/HouseFactoryInterface.php

@@ -5,7 +5,7 @@
 use Jenko\House\House;
 use Jenko\House\Location;
 
-interface HouseFactory
+interface HouseFactoryInterface
 {
     /**
      * @param Location|string|null $currentLocation

src/Jenko/House/Handler/EnterRoomHandler.php

@@ -2,15 +2,26 @@
 
 namespace Jenko\House\Handler;
 
+use Jenko\House\Event\EventDispatcherInterface;
 use Jenko\House\Factory\HomeAloneHouseFactory;
+use Jenko\House\House;
 
-final class EnterRoomHandler
+final class EnterRoomHandler implements HandlerInterface
 {
+    /**
+     * @var House $house
+     */
     private $house;
 
-    public function __construct()
+    /**
+     * @var EventDispatcherInterface
+     */
+    private $dispatcher;
+
+    public function __construct(EventDispatcherInterface $dispatcher)
     {
         $this->house = HomeAloneHouseFactory::getHouse();
+        $this->dispatcher = $dispatcher;
     }
 
     /**
@@ -19,6 +30,9 @@ public function __construct()
      */
     public function handle($command)
     {
-        return $this->house->enterRoom($command->room);
+        $house = $this->house->enterRoom($command->room);
+        $this->dispatcher->dispatch($house->releaseEvents());
+
+        return $house;
     }
-}
+}

src/Jenko/House/Handler/ExitRoomHandler.php

@@ -2,15 +2,26 @@
 
 namespace Jenko\House\Handler;
 
+use Jenko\House\Event\EventDispatcherInterface;
 use Jenko\House\Factory\HomeAloneHouseFactory;
+use Jenko\House\House;
 
-final class ExitRoomHandler
+final class ExitRoomHandler implements HandlerInterface
 {
+    /**
+     * @var House $house
+     */
     private $house;
 
-    public function __construct()
+    /**
+     * @var EventDispatcherInterface
+     */
+    private $dispatcher;
+
+    public function __construct(EventDispatcherInterface $dispatcher)
     {
         $this->house = HomeAloneHouseFactory::getHouse();
+        $this->dispatcher = $dispatcher;
     }
 
     /**
@@ -19,6 +30,9 @@ public function __construct()
      */
     public function handle($command)
     {
-        return $this->house->exitToRoom($command->room);
+        $house = $this->house->exitToRoom($command->room);
+        $this->dispatcher->dispatch($house->releaseEvents());
+
+        return $house;
     }
-}
+}

src/Jenko/House/Handler/HandlerInterface.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Jenko\House\Handler;
+
+interface HandlerInterface
+{
+    /**
+     * @param $command
+     * @return mixed
+     */
+    public function handle($command);
+}

src/Jenko/House/House.php

@@ -2,10 +2,14 @@
 
 namespace Jenko\House;
 
+use Jenko\House\Event\EnteredRoomEvent;
+use Jenko\House\Event\EventGenerator;
 use Jenko\House\Exception\LocationDoesNotExistException;
 
 final class House
 {
+    use EventGenerator;
+
     /**
      * @var array
      */
@@ -80,6 +84,8 @@ public function enterRoom($room)
         $this->previousLocation = $this->currentLocation;
         $this->currentLocation = $room;
 
+        $this->raiseEvent(new EnteredRoomEvent($this->currentLocation->getName()));
+
         return $this;
     }
 

src/Jenko/HouseBundle/Controller/EnterRoomController.php

@@ -3,7 +3,7 @@
 namespace Jenko\HouseBundle\Controller;
 
 use Jenko\House\Command\EnterRoomCommand;
-use Jenko\House\Handler\EnterRoomHandler;
+use Jenko\House\Handler\HandlerInterface;
 use Jenko\House\House;
 use Symfony\Bundle\FrameworkBundle\Templating\EngineInterface;
 use Symfony\Component\HttpFoundation\Request;
@@ -16,12 +16,18 @@ class EnterRoomController
      */
     private $templating;
 
+    /**
+     * @var HandlerInterface $handler
+     */
+    private $handler;
+
     /**
      * @param EngineInterface $templating
      */
-    public function __construct(EngineInterface $templating)
+    public function __construct(EngineInterface $templating, HandlerInterface $handler)
     {
         $this->templating = $templating;
+        $this->handler = $handler;
     }
 
     /**
@@ -34,9 +40,8 @@ public function enterAction(Request $request)
         $command = new EnterRoomCommand();
         $command->room = $request->get('location');
 
-        $handler = new EnterRoomHandler();
         /** @var House $house */
-        $house = $handler->handle($command);
+        $house = $this->handler->handle($command);
 
         return $this->templating->renderResponse(
             'JenkoHouseBundle::room.html.twig',

src/Jenko/HouseBundle/Resources/config/services.yml

@@ -11,4 +11,15 @@ services:
     jenko.house.controllers.enter_room:
         class: %jenko.house.controllers.enter_room.class%
         arguments:
-            - @templating
+            - @templating
+            - @jenko.house.handlers.enter_room_handler
+
+    jenko.house.handlers.enter_room_handler:
+        class: Jenko\House\Handler\EnterRoomHandler
+        arguments:
+            - @jenko.house.adapters.symfony_event_dispatcher
+
+    jenko.house.adapters.symfony_event_dispatcher:
+        class: Jenko\House\Adapter\SymfonyEventDispatcherAdapter
+        arguments:
+            - @event_dispatcher