added export module (#538)

src/Export/ServiceExport.php

@@ -0,0 +1,54 @@
+<?php
+
+/*
+ * This file is part of the Kimai time-tracking app.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace App\Export;
+
+class ServiceExport
+{
+    /**
+     * @var RendererInterface[]
+     */
+    protected $renderer = [];
+
+    /**
+     * @param RendererInterface $renderer
+     * @return $this
+     */
+    public function addRenderer(RendererInterface $renderer)
+    {
+        $this->renderer[] = $renderer;
+
+        return $this;
+    }
+
+    /**
+     * Returns an array of export renderer.
+     *
+     * @return RendererInterface[]
+     */
+    public function getRenderer()
+    {
+        return $this->renderer;
+    }
+
+    /**
+     * @param string $id
+     * @return RendererInterface|null
+     */
+    public function getRendererById(string $id)
+    {
+        foreach ($this->renderer as $renderer) {
+            if ($renderer->getId() === $id) {
+                return $renderer;
+            }
+        }
+
+        return null;
+    }
+}