Introduce a very simple framework agnostic Event Dispatcher and Named…

…Event interface

src/EventDispatcher/EventDispatcher.php

@@ -0,0 +1,55 @@
+<?php
+
+namespace BornFree\TacticianDomainEvent\EventDispatcher;
+
+
+class EventDispatcher implements EventDispatcherInterface
+{
+    /**
+     * @var EventListenerInterface[][]
+     */
+    private $listeners = [];
+
+    /**
+     * @inheritdoc
+     */
+    public function dispatch($event)
+    {
+        $name = $event instanceof NamedEvent ? $event->getName() : get_class($event);
+
+        foreach ($this->getListeners($name) as $listener) {
+            $listener->handle($event);
+        }
+    }
+
+    /**
+     * @param string $eventName
+     * @param EventListenerInterface $listener
+     */
+    public function addListener($eventName, EventListenerInterface $listener)
+    {
+        $this->listeners[$eventName][] = $listener;
+    }
+
+    /**
+     * @param string $eventName
+     * @return EventListenerInterface[]
+     */
+    public function getListeners($eventName)
+    {
+        if (! $this->hasListeners($eventName)) {
+            return [];
+        }
+
+        return $this->listeners[$eventName];
+    }
+
+    /**
+     * @param string $eventName
+     * @return bool
+     */
+    public function hasListeners($eventName)
+    {
+        return isset($this->listeners[$eventName]);
+    }
+}

src/EventBus.php → src/EventDispatcher/EventDispatcherInterface.php

@@ -1,8 +1,8 @@
 <?php
 
-namespace BornFree\TacticianDomainEvent;
+namespace BornFree\TacticianDomainEvent\EventDispatcher;
 
-interface EventBus
+interface EventDispatcherInterface
 {
     /**
      * Dispatches an event

src/EventDispatcher/EventListenerInterface.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace BornFree\TacticianDomainEvent\EventDispatcher;
+
+interface EventListenerInterface
+{
+    /**
+     * Handles an event
+     *
+     * @param mixed $event
+     */
+    public function handle($event);
+}

src/EventDispatcher/NamedEvent.php

@@ -0,0 +1,11 @@
+<?php
+
+namespace BornFree\TacticianDomainEvent\EventDispatcher;
+
+interface NamedEvent
+{
+    /**
+     * @return string
+     */
+    public function getName();
+}

src/Middleware/ReleaseRecordedEventsMiddleware.php

@@ -2,7 +2,7 @@
 
 namespace BornFree\TacticianDomainEvent\Middleware;
 
-use BornFree\TacticianDomainEvent\EventBus;
+use BornFree\TacticianDomainEvent\EventDispatcher\EventDispatcherInterface;
 use BornFree\TacticianDomainEvent\Recorder\ContainsRecordedEvents;
 use League\Tactician\Middleware;
 
@@ -14,20 +14,20 @@ class ReleaseRecordedEventsMiddleware implements Middleware
     private $eventRecorder;
 
     /**
-     * @var EventBus
+     * @var EventDispatcherInterface
      */
-    private $eventBus;
+    private $eventDispatcher;
 
     /**
      * ReleaseRecorderEventsMiddleware constructor.
      *
      * @param ContainsRecordedEvents $eventRecorder
-     * @param EventBus $eventBus
+     * @param EventDispatcherInterface $eventDispatcher
      */
-    public function __construct(ContainsRecordedEvents $eventRecorder, EventBus $eventBus)
+    public function __construct(ContainsRecordedEvents $eventRecorder, EventDispatcherInterface $eventDispatcher)
     {
         $this->eventRecorder = $eventRecorder;
-        $this->eventBus = $eventBus;
+        $this->eventDispatcher = $eventDispatcher;
     }
 
     /**
@@ -53,7 +53,7 @@ public function execute($command, callable $next)
         $recordedEvents = $this->eventRecorder->releaseEvents();
 
         foreach ($recordedEvents as $event) {
-            $this->eventBus->dispatch($event);
+            $this->eventDispatcher->dispatch($event);
         }
     }
 }