Elasticsearch的javaAPI之percolator

Elasticsearch的javaAPI之percolator

 

percolator同意一个在index中注冊queries,然后发送包括doc的请求,返回得到在index中注冊过的而且匹配doc的query

//This is the query we're registering in the percolator

QueryBuilder qb = termQuery("content", "amazing");

//Index the query = register it in the percolator

client.prepareIndex("myIndexName", ".percolator", "myDesignatedQueryName")

    .setSource(jsonBuilder()

        .startObject()

            .field("query", qb) // Register the query

        .endObject())

    .setRefresh(true) // Needed when the query shall be available immediately

    .execute().actionGet();

在上面的index中query名为myDesignatedQueryName。

为了检查文档注冊查询,使用这个 代码:

//Build a document to check against the percolator

XContentBuilder docBuilder = XContentFactory.jsonBuilder().startObject();

docBuilder.field("doc").startObject(); //This is needed to designate the document

docBuilder.field("content", "This is amazing!");

docBuilder.endObject(); //End of the doc field

docBuilder.endObject(); //End of the JSON root object

//Percolate

PercolateResponse response = client.preparePercolate()

                        .setIndices("myIndexName")

                        .setDocumentType("myDocumentType")

                        .setSource(docBuilder).execute().actionGet();

//Iterate over the results

for(PercolateResponse.Match match : response) {

    //Handle the result which is the name of

    //the query in the percolator

}

 

传统设计基于数据的documents，并将它们存储到一个index中,然后通过搜索api定义的查询。获取这些documents。Percolator正好相反,首先你储存到一个查询到index,然后通过percolatorapi以获取这些查询。

查询能够存储的原因来自这样一个事实:在Elasticsearch中document和query都定义为json格式。这同意您通过index api将query嵌入到document中。 Elasticsearch能够依赖percolator，通过document来提取查询。 既然document也定义为json,您能够定义一个percolator在document的请求中。

percolator和它的大部分功能在实时工作,所以percolator query被存入，那么久能够使用percolator

依据mapping，创建一个index， field：message

curl -XPUT 'localhost:9200/my-index' -d '{

  "mappings": {

    "my-type": {

      "properties": {

        "message": {

          "type": "string"

        }

      }

    }

  }

}

注冊一个query到percolator中：

curl -XPUT 'localhost:9200/my-index/.percolator/1' -d '{

    "query" : {

        "match" : {

            "message" : "bonsai tree"

        }

    }

}'

用一个符合注冊的percolator query的document：

curl -XGET 'localhost:9200/my-index/message/_percolate' -d '{

    "doc" : {

        "message" : "A new bonsai tree in the office"

    }

}'

上面的请求将返回以下的信息：

{

    "took" : 19,

    "_shards" : {

        "total" : 5,

        "successful" : 5,

        "failed" : 0

    },

    "total" : 1,

    "matches" : [

        {

          "_index" : "my-index",

          "_id" : "1"

        }

    ]

}

原文地址：

http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-percolate.html#search-percolate

http://www.elasticsearch.org/guide/en/elasticsearch/client/java-api/current/percolate.html

翻译欠佳，希望不会对大家造成误解