code: @SuppressWarnings("unchecked")
      @Override
      public Map<String, Object> get(String spaceId, String key) throws IOException {
          String cacheKey = calcCacheKey(spaceId, key);
          Map<String, Object> data = getFromCache(getCacheName(), cacheKey, Map.class);
          if (data == null) {
              data = kdStorage.get(spaceId, key);
              putToCache(getCacheName(), cacheKey, data);
          }
          return data;
      }
docs: {@inheritDoc}