redis keys in easier way

test/unit/cartodb/rate-limit.test.js

@@ -5,7 +5,7 @@ const cartodbRedis = require('cartodb-redis');
 const {
     rateLimitMiddleware,
     RATE_LIMIT_ENDPOINTS_GROUPS,
-    RATE_LIMIT_STORE_KEY
+    getStoreKey
 } =  require('../../../lib/cartodb/middleware/rate-limit');
 
 let redisClient;
@@ -19,7 +19,7 @@ function setLimit(count, period, burst) {
             return;
         }
 
-        const key = RATE_LIMIT_STORE_KEY + user + ':' + RATE_LIMIT_ENDPOINTS_GROUPS.ENDPOINT_8;
+        const key = getStoreKey(user, RATE_LIMIT_ENDPOINTS_GROUPS.ENDPOINT_8);
         redisClient.hset(key, 'b', burst, 'c', count, 'p', period, function() {
             keysToDelete.push(key);
         });