ElasticSearch 转换 Rest 查询嵌套字段到客户端 Scala/Java 代码

Question

我找不到有关如何将嵌套查询从 ES 官方示例转换为 Scala/Java 代码的文档

https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-nested-query.html

GET my-index-000001/_search
{
  "query": {
    "nested": {
      "path": "user",
      "query": {
        "bool": {
          "must": [
            { "match": { "user.first": "Alice" }},
            { "match": { "user.last":  "Smith" }} 
          ]
        }
      }
    }
  }
}

在 Scala 我试过

  import org.elasticsearch.index.query.QueryBuilders._
  ...

  val q = boolQuery()
  q.must(termQuery("user.first", "Alice"))
  q.must(termQuery("user.last", "White))
  nestedQuery("user", q, ScoreMode.None)
        

但是在检查结果查询时它是不一样的。

结果查询类似于（它的裁剪版本，因为原始查询要大得多）：

 "nested" : {
                            "query" : {
                              "bool" : {
                                "must" : [
                                  {
                                    "match" : {
                                      "user.first" : {
                                        "query" : "Alice",
                                        "operator" : "OR",
                                        "prefix_length" : 0,
                                        "max_expansions" : 50,
                                        "fuzzy_transpositions" : true,
                                        "lenient" : false,
                                        "zero_terms_query" : "NONE",
                                        "auto_generate_synonyms_phrase_query" : true,
                                        "boost" : 1.0
                                      }
                                    }
                                  },
                                  {
                                    "match" : {
                                      "user.last" : {
                                        "query" : "Smith",
                                        "operator" : "OR",
                                        "prefix_length" : 0,
                                        "max_expansions" : 50,
                                        "fuzzy_transpositions" : true,
                                        "lenient" : false,
                                        "zero_terms_query" : "NONE",
                                        "auto_generate_synonyms_phrase_query" : true,
                                        "boost" : 1.0
                                      }
                                    }
                                  }
                                ],
                                "adjust_pure_negative" : true,
                                "boost" : 1.0
                              }
                            },
                            "path" : "user",
                            "ignore_unmapped" : false,
                            "score_mode" : "none",
                            "boost" : 1.0
                          }
                        }

我得到的实际异常是在单元测试中：

. java.io.NotSerializableException: org.elasticsearch.client.Response
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1184)
    at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputSt[info] - should excluded keywords only *** FAILED ***
[info]   org.elasticsearch.ElasticsearchStatusException: Elasticsearch exception [type=search_phase_execution_exception, reason=all shards failed]
[info]   at org.elasticsearch.rest.BytesRestResponse.errorFromXContent(BytesRestResponse.java:176)
[info]   at org.elasticsearch.client.RestHighLevelClient.parseEntity(RestHighLevelClient.java:1933)
[info]   at org.elasticsearch.client.RestHighLevelClient.parseResponseException(RestHighLevelClient.java:1910)
[info]   at org.elasticsearch.client.RestHighLevelClient.internalPerformRequest(RestHighLevelClient.java:1667)
[info]   at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:1624)
ream.java:1509)
    at java.io.Obje[info]   at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:1594)
[info]   at org.elasticsearch.client.RestHighLevelClient.search(RestHighLevelClient.java:1110)

Answer 1

您的 Scala 代码正在生成正确的查询。 基本上这里发生的是，它在查询中添加了一些带有值的默认参数，因此，与原始查询相比，您的查询看起来更大。 这是由 Java 和 Scala elasticsearch 客户端完成的（可能是其他语言客户端也在做同样的事情）。 此外，当您在 Kibana 中创建 DSL 查询时，运行时会将所有默认参数添加到您的查询中。

以下是查询中具有默认值的参数：

"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1.0

下面我删除了通过代码添加到您的查询中的所有默认参数：

{
    "nested": {
        "query": {
            "bool": {
                "must": [
                    {
                        "match": {
                            "user.first": {
                                "query": "Alice"
                            }
                        }
                    },
                    {
                        "match": {
                            "user.last": {
                                "query": "Smith"
                            }
                        }
                    }
                ]
            }
        },
        "path": "user"
        
    }
}