Make definition mapper independent of the data format.

src/Netzmacht/Contao/Leaflet/Subscriber/HashSubscriber.php

@@ -0,0 +1,66 @@
+<?php
+
+/**
+ * @package    dev
+ * @author     David Molineus <david.molineus@netzmacht.de>
+ * @copyright  2015 netzmacht creative David Molineus
+ * @license    LGPL 3.0
+ * @filesource
+ *
+ */
+
+namespace Netzmacht\Contao\Leaflet\Subscriber;
+
+
+use Netzmacht\Contao\Leaflet\Event\GetHashEvent;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+class HashSubscriber implements EventSubscriberInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public static function getSubscribedEvents()
+    {
+        return array(
+            GetHashEvent::NAME => array(
+                array('getModelHash'),
+                array('getFallback', -100)
+            )
+        );
+    }
+
+    /**
+     * Get hash for a model object.
+     *
+     * @param GetHashEvent $event
+     */
+    public function getModelHash(GetHashEvent $event)
+    {
+        $data = $event->getData();
+
+        if ($data instanceof \Model) {
+            $event->setHash($data->getTable() . '.' . $data->{$data->getPk()});
+        }
+    }
+
+    /**
+     * Get hash fallback if no hash was created so far.
+     *
+     * @param GetHashEvent $event
+     */
+    public function getFallback(GetHashEvent $event)
+    {
+        if ($event->getHash()) {
+            return;
+        }
+
+        $data = $event->getData();
+
+        if (is_object($data)) {
+            $event->setHash(spl_object_hash($data));
+        } else {
+            $event->setHash(md5(json_encode($data)));
+        }
+    }
+}