ElasticSearch - SpringBoot整合ES：解析搜索返回字段

Posted 2023-03-22 我一直在流浪

tags:

篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了ElasticSearch - SpringBoot整合ES：解析搜索返回字段相关的知识，希望对你有一定的参考价值。

文章目录

ElasticSearch - SpringBoot整合ES之获取搜索结果

1. 数据构造

索引2个文档到 hotel 索引中：

PUT /hotel/_doc/1

  "title": "文雅酒店",
  "city": "青岛",
  "price": 556,
  "create_time": "20200418120000",
  "amenities": "浴池,普通停车场/充电停车场",
  "full_room": false,
  "location": 
    "lat": 36.083078,
    "lon": 120.37566
  ,
  "praise": 10


PUT /hotel/_doc/2

  "title": "金都嘉怡假日酒店",
  "city": "北京",
  "price": 337,
  "create_time": "20210315200000",
  "amenities": "wifi,充电停车场/可升降停车场",
  "full_room": false,
  "location": 
    "lat": 39.915153,
    "lon": 116.403
  ,
  "praise": 60

2. ElasticSearch 查询集群中所有索引中的所有文档

 GET /hotel/_search


  "took" : 499,
  "timed_out" : false,
  "_shards" : 
    "total" : 5,
    "successful" : 5,
    "skipped" : 0,
    "failed" : 0
  ,
  "hits" : 
    "total" : 
      "value" : 2,
      "relation" : "eq"
    ,
    "max_score" : 1.0,
    "hits" : [
      
        "_index" : "hotel",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : 
          "title" : "金都嘉怡假日酒店",
          "city" : "北京",
          "price" : 337,
          "create_time" : "20210315200000",
          "amenities" : "wifi,充电停车场/可升降停车场",
          "full_room" : false,
          "location" : 
            "lat" : 39.915153,
            "lon" : 116.403
          ,
          "praise" : 60
        
      ,
      
        "_index" : "hotel",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : 
          "title" : "文雅酒店",
          "city" : "青岛",
          "price" : 556,
          "create_time" : "20200418120000",
          "amenities" : "浴池,普通停车场/充电停车场",
          "full_room" : false,
          "location" : 
            "lat" : 36.083078,
            "lon" : 120.37566
          ,
          "praise" : 10
        
      
    ]

3. ElasticSearch 搜索结果字段解析

1. took 搜索请求耗费了多少毫秒

took 值告诉我们执行整个搜索请求耗费了多少毫秒。

2. shards 查询中参与分片的总数

_shards 部分告诉我们在查询中参与分片的总数，以及这些分片成功了多少个失败了多少个。正常情况下我们不希望分片失败，但是分片失败是可能发生的。如果我们遭遇到一种灾难级别的故障，在这个故障中丢失了相同分片的原始数据和副本，那么对这个分片将没有可用副本来对搜索请求作出响应。假若这样，Elasticsearch 将报告这个分片是失败的，但是会继续返回剩余分片的结果。

3. timed_out 查询是否超时

timed_out 值告诉我们查询是否超时。默认情况下，搜索请求不会超时。

4. hits 表示搜索结果

返回结果中最重要的部分是 hits ，它包含 total 字段来表示匹配到的文档总数，并且一个 hits 数组包含所查询结果的前十个文档。在解析搜索结果时，我们通常需要关注以下几个字段：

hits.total.value：匹配的文档总数。
hits.max_score：与查询所匹配文档的_score的最大值。
hits.hits：匹配的文档列表。
hits.hits._source：匹配的文档的原始数据。
hits.hits._score：匹配的文档的分数。它衡量了文档与查询的匹配程度,默认情况下，首先返回最相关的文档结果，就是说，返回的文档是按照score 降序排列的。
hits.hits.highlight：匹配的文档的高亮显示信息。

4. SpringBoot 整合ElasticSearch获取搜索结果

@Slf4j
@Service
public class ElasticSearchImpl 

    @Autowired
    private RestHighLevelClient restHighLevelClient;

    public void searchUser() throws IOException 
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        SearchRequest searchRequest = new SearchRequest(new String[]"hotel",searchSourceBuilder);
        SearchResponse searchResponse = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);

        TimeValue took = searchResponse.getTook();
        System.out.println("took = " + took);

        // 搜索结果
        SearchHits searchHits = searchResponse.getHits();

        // hits.total.value:匹配的文档总数
        TotalHits totalHits = searchHits.getTotalHits();
        long value = totalHits.value;
        System.out.println("value = " + value);

        // hits.max_score:与查询所匹配文档的_score的最大值
        float maxScore = searchHits.getMaxScore();
        System.out.println("maxScore = " + maxScore);

        // hits.hits:匹配的文档列表
        SearchHit[] hits = searchHits.getHits();
        for (SearchHit hit : hits) 
            // hits.hits._source：匹配的文档的原始数据
            String sourceAsString = hit.getSourceAsString();
            System.out.println("sourceAsString = " + sourceAsString);

            //  hits.hits._id：匹配的文档的id
            String id = hit.getId();
            System.out.println("id = " + id);

            Map<String, DocumentField> fields = hit.getFields();
            System.out.println("fields = " + fields);

            String index = hit.getIndex();
            System.out.println("index = " + index);

            float score = hit.getScore();
            System.out.println("score = " + score);
        
        System.out.println(searchResponse);

took=2ms
value = 2
maxScore = 1.0

sourceAsString = "title":"金都嘉怡假日酒店","city":"北京","price":337,"create_time":"20210315200000","amenities":"wifi,充电停车场/可升降停车场","full_room":false,"location":"lat":39.915153,"lon":116.403,"praise":60
id = 2
fields = 
index = hotel
score = 1.0

sourceAsString = "title":"文雅酒店","city":"青岛","price":556,"create_time":"20200418120000","amenities":"浴池,普通停车场/充电停车场","full_room":false,"location":"lat":36.083078,"lon":120.37566,"praise":10
id = 1
fields = 
index = hotel
score = 1.0


    "took": 2,
    "timed_out": false,
    "_shards": 
        "total": 5,
        "successful": 5,
        "skipped": 0,
        "failed": 0
    ,
    "hits": 
        "total": 
            "value": 2,
            "relation": "eq"
        ,
        "max_score": 1.0,
        "hits": [
            
                "_index": "hotel",
                "_type": "_doc",
                "_id": "2",
                "_score": 1.0,
                "_source": 
                    "title": "金都嘉怡假日酒店",
                    "city": "北京",
                    "price": 337,
                    "create_time": "20210315200000",
                    "amenities": "wifi,充电停车场/可升降停车场",
                    "full_room": false,
                    "location": 
                        "lat": 39.915153,
                        "lon": 116.403
                    ,
                    "praise": 60
                
            ,
            
                "_index": "hotel",
                "_type": "_doc",
                "_id": "1",
                "_score": 1.0,
                "_source": 
                    "title": "文雅酒店",
                    "city": "青岛",
                    "price": 556,
                    "create_time": "20200418120000",
                    "amenities": "浴池,普通停车场/充电停车场",
                    "full_room": false,
                    "location": 
                        "lat": 36.083078,
                        "lon": 120.37566
                    ,
                    "praise": 10
                
            
        ]