Implement custom route for data request to prevent partial rendering of the page and it's possible issues (f.e. form captcha changes) (Close #49).

src/Frontend/PageIdDeterminator.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * Leaflet maps for Contao CMS.
+ *
+ * @package    contao-leaflet-maps
+ * @author     David Molineus <david.molineus@netzmacht.de>
+ * @copyright  2014-2018 netzmacht David Molineus. All rights reserved.
+ * @license    LGPL-3.0 https://github.com/netzmacht/contao-leaflet-maps/blob/master/LICENSE
+ * @filesource
+ */
+
+declare(strict_types=1);
+
+namespace Netzmacht\Contao\Leaflet\Frontend;
+
+use Netzmacht\Contao\PageContext\Exception\DeterminePageIdFailed;
+use Netzmacht\Contao\PageContext\Request\PageIdDeterminator as PageContextPageIdDeterminator;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Class ApiPageIdDeterminator
+ */
+final class PageIdDeterminator implements PageContextPageIdDeterminator
+{
+    /**
+     * {@inheritDoc}
+     */
+    public function match(Request $request): bool
+    {
+        return ($request->attributes->get('_leaflet_scope') === 'page' && $request->query->get('context') === 'page');
+    }
+
+    /**
+     * {@inheritDoc}
+     *
+     * @throws DeterminePageIdFailed When no context id is given.
+     */
+    public function determinate(Request $request): int
+    {
+        if (!$request->query->has('contextId')) {
+            throw new DeterminePageIdFailed('Could not determine page id for from request.');
+        }
+
+        return $request->query->getInt('contextId');
+    }
+}