Doctrine\Common\Cache\RedisCache::doFetchMultiple PHP Method

    protected function doFetchMultiple(array $keys)
    {
        $fetchedItems = array_combine($keys, $this->redis->mget($keys));
        // Redis mget returns false for keys that do not exist. So we need to filter those out unless it's the real data.
        $foundItems = [];
        foreach ($fetchedItems as $key => $value) {
            if (false !== $value || $this->redis->exists($key)) {
                $foundItems[$key] = $value;
            }
        }
        return $foundItems;
    }