elasticsearch - 编写NEST查询以按分数对聚合存储桶进行排序

Question

我想要的是为每个unitId(这是我的文档中的一个字段)创建一个聚合存储桶。我希望每个存储桶按该存储桶中的最高得分排序。我写了下面的查询，它可以满足我的要求:

 "aggs": {
    "UnitAggregationBucket": {
      "terms": {
        "field": "unitId",
        "size": 10,
        "order": {
          "max_score": "desc"
        }
      },
      "aggs": {
        "max_score": {
          "max": {
            "script": "_score"
          }
        }
      }
    }

我正在使用脚本在子聚合中查找每个存储桶的最高得分。我不知道如何使用NEST编写上述查询？

Answer 1

更新:

这是我从Elastic Community得到的答案:

With 6.x, this would be something like:

var client = new ElasticClient();

var searchResponse = client.Search<object>(s => s
    .Aggregations(a => a
          .Terms("UnitAggregationBucket", t => t
              .Field("unitId")
          .Size(10)
          .Order(o => o
              .Descending("maximum_score")
          )           
            .Aggregations(aa => aa
              .Max("maximum_score", m => m
                  .Script("_score")
              )
          )
      )
  ) 
);

var termsAgg = searchResponse.Aggregations.Terms("UnitAggregationBucket");

foreach(var bucket in termsAgg.Buckets)
{     
    // do something with buckets  
    var maxScore = bucket.Max("maximum_score").Value; 
}

Note that you can't use max_score for the name of the aggregation as it's a reserved keyword name in the client, which the client uses in its heuristics based aggregation response JSON deserialization method.

原始答案

我设法编写了以下NEST查询:

var unitAggregations = new TermsAggregation("UnitAggregationBucket")
{
    Size 10,
    Field = Field<MyDocument>(p => p.UnitId),
    Order = new List<TermsOrder>
    {
        new TermsOrder()
        {
            Key = "max_score_in_bucket",
            Order = SortOrder.Descending
        }
    },
    Aggregations = new MaxAggregation("max_score_in_bucket", string.Empty)
    {
        Script = new InlineScript("_score")
    }
};

产生以下json:

"aggs": {
    "UnitAggregationBucket": {
      "aggs": {
        "max_score_in_bucket": {
          "max": {
            "script": {
              "source": "_score"
            }
          }
        }
      },
      "terms": {
        "field": "unitId",
        "order": [
          {
            "max_score_in_bucket": "desc"
          }
        ],
        "size": 10
      }
    }
  }

它不是我想要的确切json，但它可以满足我的要求。

注意: max_score是Elasticsearch中的保留关键字，因此我不得不使用其他名称: max_score_in_bucket