select options for products + skus, photos form

src/Controller/ProductSkusController.php

@@ -239,4 +239,18 @@ class ProductSkusController extends AppController
 
         return $this->redirect(['action' => 'index']);
     }
+
+    /**
+     * @return \Cake\Http\Response|null|void Renders view
+     */
+    public function select()
+    {
+        $productSkus = $this->getTable()
+            ->find('list')
+            ->where(['product_id' => $this->request->getQuery('product_id', '-1')])
+            ->orderBy(['sku'])
+            ->toArray();
+
+        $this->set(compact('productSkus'));
+    }
 }