elasticsearch 在Elasticsearch的脚本字段中获取自定义计算值

我想在弹性搜索中获得脚本字段中两个值的乘积，如图所示。如何做到这一点

我正在使用下面的聚合代码

{
    "aggs": {
        "mention": {
            "terms": {
                "size": 20,
                "field": "username"
            },
            "aggs": {
                "mention_hits": {
                    "top_hits": {
                        "sort": [
                            {
                                "published_date": {
                                    "order": "desc"
                                }
                            }
                        ],
                        "_source": {
                            "include": [
                                "klout"
                            ]
                        },
                        "size": 1
                    }
                },
                "user_ranking": {
                    "max": {
                        "script": " 123 "
                    }
                }
            }
        }
    }
}