MAGETWO-65484: [Backport] - [Performance] Caching of attribute options for Layered Navigation - for 2.1.6

Author: vzabaznov

app/code/Magento/Eav/Model/Entity/Attribute/Frontend/AbstractFrontend.php

@@ -11,8 +11,29 @@
  */
 namespace Magento\Eav\Model\Entity\Attribute\Frontend;
 
+use Magento\Framework\App\CacheInterface;
+use Magento\Store\Api\StoreResolverInterface;
+use Magento\Framework\App\ObjectManager;
+use Magento\Eav\Model\Cache\Type as CacheType;
+use Magento\Eav\Model\Entity\Attribute;
+
 abstract class AbstractFrontend implements \Magento\Eav\Model\Entity\Attribute\Frontend\FrontendInterface
 {
+    /**
+     * @var CacheInterface
+     */
+    private $cache;
+
+    /**
+     * @var StoreResolverInterface
+     */
+    private $storeResolver;
+
+    /**
+     * @var array
+     */
+    private $cacheTags;
+
     /**
      * Reference to the attribute instance
      *
@@ -27,11 +48,24 @@ abstract class AbstractFrontend implements \Magento\Eav\Model\Entity\Attribute\F
 
     /**
      * @param \Magento\Eav\Model\Entity\Attribute\Source\BooleanFactory $attrBooleanFactory
+     * @param CacheInterface $cache
+     * @param StoreResolverInterface $storeResolver
+     * @param array $cacheTags
      * @codeCoverageIgnore
      */
-    public function __construct(\Magento\Eav\Model\Entity\Attribute\Source\BooleanFactory $attrBooleanFactory)
-    {
+    public function __construct(
+        \Magento\Eav\Model\Entity\Attribute\Source\BooleanFactory $attrBooleanFactory,
+        CacheInterface $cache = null,
+        StoreResolverInterface $storeResolver = null,
+        array $cacheTags = [
+        CacheType::CACHE_TAG,
+        Attribute::CACHE_TAG,
+        ]
+    ) {
         $this->_attrBooleanFactory = $attrBooleanFactory;
+        $this->cache = $cache ?: ObjectManager::getInstance()->get(CacheInterface::class);
+        $this->storeResolver = $storeResolver ?: ObjectManager::getInstance()->get(StoreResolverInterface::class);
+        $this->cacheTags = $cacheTags;
     }
 
     /**
@@ -216,7 +250,21 @@ public function getConfigField($fieldName)
      */
     public function getSelectOptions()
     {
-        return $this->getAttribute()->getSource()->getAllOptions();
+        $cacheKey = 'attribute-navigation-option-' .
+            $this->getAttribute()->getAttributeCode() . '-' .
+            $this->storeResolver->getCurrentStoreId();
+        $optionString = $this->cache->load($cacheKey);
+        if (false === $optionString) {
+            $options = $this->getAttribute()->getSource()->getAllOptions();
+            $this->cache->save(
+                json_encode($options),
+                $cacheKey,
+                $this->cacheTags
+            );
+        } else {
+            $options = json_decode($optionString, true);
+        }
+        return $options;
     }
 
     /**