优化search cache key生成规则

@@ -3,7 +3,6 @@
  */
 'use strict';
 const _ = require('lodash');
-const Fn = require('lodash/fp');
 const md5 = require('md5');
 
 const config = global.yoho.config;
@@ -22,13 +21,15 @@ const GLOBAL_BASE_URI = '/product/global/list';
 
 // 缓存生效时间
 const CACHE_TIME_S = 60;
+const UNUSEDKEY = ['page', 'limit', 'need_filter', 'order'];
 
 function getSearchCacheKey(params) {
-    let removeUnusedKey = Fn.omit(['page', 'limit', 'need_filter', 'order']);
-    let sortByKey = Fn.pipe(Fn.toPairs, Fn.sortBy(0), Fn.flatten);
-    let genKey = Fn.pipe(Fn.cloneDeep, removeUnusedKey, sortByKey, Fn.join('_'));
+    const paramList = Object.keys(params)
+    .filter(k => !_.some(UNUSEDKEY, key => key === k))
+    .sort();
+    const paramsStr = _.join(_.map(paramList, k => `${k}_${params[k] || ''}`), '_');
 
-    return 'search_custom_' + md5(genKey(params));
+    return 'search_custom_' + md5(paramsStr);
 }
 
 function _saveCache(key, kv, cacheTime) {