code review by fei.hong: do modify add the second grade cache check when call ap…

…i error increment five times set data to first grade cache

@@ -71,6 +71,20 @@ class Cache
             else {
                 $result = HoodCache::Memcached($node)->get(self::makeKey($key, $node));
             }
+            
+            // 当接口异常，一级缓存没取到数据的情况
+            if ($node === 'slave') {
+                $incrementKey = self::makeKey('_increment_' . $key, 'slave');
+                $incrementValue = HoodCache::Memcached('slave')->get($incrementKey, 'slave');
+                // 接口调用失败累计5次之后，回填二级缓存数据到一级缓存
+                if (is_int($incrementValue) && $incrementValue > 5) {
+                    HoodCache::Memcached('master')->set(self::makeKey($key, 'master'), $result, 300);
+                } 
+                // 接口调用失败次数累加
+                else {
+                    HoodCache::Memcached('slave')->increment($incrementKey, 1, 0, 3600);
+                }
+            }
         } catch (Exception $e) {
             $result = array();
         }
@@ -97,6 +111,32 @@ class Cache
             HoodCache::Memcached('slave')->delete(self::makeKey($key, 'slave'));
         }
     }
+    
+    /**
+     * 累加
+     * 
+     * @param string $key
+     * @param int $offset
+     * @param int $initialValue
+     * @param int $expiry
+     * @return boolean
+     */
+    public static function increment($key, $offset = 1, $initialValue = 0, $expiry = 0)
+    {
+        return HoodCache::Memcached('master')->increment(self::makeKey($key, 'master'), $offset, $initialValue, $expiry);
+    }
+
+    /**
+     * 递减
+     * 
+     * @param string $key
+     * @param int $offset
+     * @return boolean
+     */
+    public static function decrement($key, $offset = 1)
+    {
+        return HoodCache::Memcached('master')->decrement(self::makeKey($key, 'master'), $offset);
+    }
 
     /**
      * 生成键名