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Question

我很难理解如何突出显示工作。
我的查询正在返回该项目，但是我看不到会导致突出显示的标签。

这是测试索引的设置:

curl -XPUT 'http://localhost:9200/testfoo' -d '{
    "mappings": {
        "entry": {
            "properties": {
                "id": { "type": "integer" },
                "owner": { "type": "string" },
                "target": {
                    "properties": {
                        "id": { "type": "integer" },
                        "type": {
                            "type": "string",
                            "index": "not_analyzed"
                        }
                    }
                },
                "body": { "type": "string" },
                "body_plain": { "type": "string"}
            }
        }
    }
}'

这是几个插入的文档:

curl -XPUT 'http://localhost:9200/testfoo/entry/1' -d'{
    "id": 1,
    "owner": "me",
    "target": {
        "type": "event",
        "id":   100
    },
    "body": "<div>Message One has foobar in it</div>",
    "body_plain": "Message One has foobar in it"
}'

curl -XPUT 'http://localhost:9200/testfoo/entry/2' -d'{
    "id": 2,
    "owner": "me",
    "target": {
        "type": "event",
        "id":   200
    },
    "body": "<div>Message One has no bar in it</div>",
    "body_plain": "Message One has no bar in it"
}'

简单搜索将返回预期的文档:

curl -XPOST 'http://localhost:9200/testfoo/_search?pretty' -d '{
    "query": {
        "simple_query_string": {
            "query": "foobar"
        }
    }
}'
{
  "took" : 1,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 1,
    "max_score" : 0.09492774,
    "hits" : [ {
      "_index" : "testfoo",
      "_type" : "entry",
      "_id" : "1",
      "_score" : 0.09492774,
      "_source" : {
        "id" : 1,
        "owner" : "me",
        "target" : {
          "type" : "event",
          "id" : 100
        },
        "body" : "<div>Message One has foobar in it</div>",
        "body_plain" : "Message One has foobar in it"
      }
    } ]
  }
}

但是，当我添加“突出显示”时，我得到了相同的JSON，但body_plain却没有与匹配项“突出显示”:

curl -XPOST 'http://localhost:9200/testfoo/_search?pretty' -d '{
    "query":{
            "query": {
                "simple_query_string":{
                    "query":"foobar"
                }
            }
    },
    "highlight": {
        "pre_tags": [ "<div class=\"highlight\">" ],
        "post_tags": [ "</div>" ],
        "fields": {
            "_all": {
                "fragment_size": 10,
                "number_of_fragments": 1
            }
        }
    },
    "sort": [
        "_score"
    ],
    "_source": [ "target", "id", "body_plain", "body" ],
    "min_score": 0.9,
    "size":10
}'
{
  "took" : 2,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 1,
    "max_score" : 1.0,
    "hits" : [ {
      "_index" : "testfoo",
      "_type" : "entry",
      "_id" : "1",
      "_score" : 1.0,
      "_source" : {
        "id" : 1,
        "body" : "<div>Message One has foobar in it</div>",
        "target" : {
          "id" : 100,
          "type" : "event"
        },
        "body_plain" : "Message One has foobar in it"
      }
    } ]
  }
}

我期望body_plain看起来像什么

  Message One has <div class="highlight">foobar</div> in it

想知道我在做什么错。谢谢。

Answer 1

从official documentation

In order to perform highlighting, the actual content of the field is required. If the field in question is stored (has store set to true in the mapping) it will be used, otherwise, the actual _source will be loaded and the relevant field will be extracted from it.

The _all field cannot be extracted from _source, so it can only be used for highlighting if it mapped to have store set to true.

您有两种方法可以解决此问题。您可以更改映射以存储_all字段:

{
  "mappings": {
    "entry": {
      "_all": {              <-- add this
        "store": true
      },
      "properties": {
        ...

或者您将查询更改为此:

curl -XPOST 'http://localhost:9200/testfoo/_search?pretty' -d '{
    "query":{
            "query": {
                "simple_query_string":{
                    "query":"foobar"
                }
            }
    },
    "highlight": {
        "pre_tags": [ "<div class=\"highlight\">" ],
        "post_tags": [ "</div>" ],
        "require_field_match": false,             <-- add this
        "fields": {
            "*": {                                <-- use this                  
                "fragment_size": 10,
                "number_of_fragments": 1
            }
        }
    },
    "sort": [
        "_score"
    ],
    "_source": [ "target", "id", "body_plain", "body" ],
    "min_score": 0.9,
    "size":10
}'