public function getInsights()
    {
        $cacheKey = sprintf(
            '__watson_personality_insights_%s_',
            md5(serialize($this->contentItems))
        );

        if (!$result = unserialize($this->cache->get($cacheKey)) || !$this->config->cache) {
            $result = $this->request->request($this->config, $this->contentItems);
            $this->cache->put($cacheKey, serialize($result), 9999999);
        }

        return $result;
    }