一尘不染

Elastic search父子数据搜索Java API

elasticsearch

我是ELastic搜索的新手。

elasticsearch中的数据在父子模型中。我想使用Java API在此数据中执行搜索。

父类型包含作者详细信息,子类型包含书籍详细信息,例如书籍名称,书籍出版商,书籍类别。

在搜索子项详细信息时,我还需要获取父项详细信息,反之亦然。有时,搜索条件将取决于父类型以及子类型。例如搜索由author1和撰写的书籍Fiction

我如何在Java中实现呢?我已经参考了elasticsearch文档,但无法找到解决方案

请帮忙


阅读 855

收藏
2020-06-22

共1个答案

一尘不染

首先使用parent/child映射设置索引。在下面的映射中,我还添加了一个未标记的字段,categories以便您可以对该字段执行过滤器查询。(对于创建索引和文档,我使用的是JSONAPI而不是JavaAPI,因为这不是问题的一部分。)

POST /test
{
    "mappings": {
        "book": {
            "_parent": {
                "type": "author"
            },
            "properties":{
                "category":{
                    "type":"string",
                    "fields":{
                        "raw":{
                            "type":"string",
                            "index": "not_analyzed"
                        }
                    }
                }
            }
        }
    }
}

创建一些author文档:

POST /test/author/1
{
    "name": "jon doe"
}


POST /test/author/2
{
    "name": "jane smith"
}

创建一些book文档,指定请求之间book和之间的关系author

POST /test/book/12?parent=1
{
    "name": "fictional book",
    "category": "Fiction",
    "publisher": "publisher1"
}

POST /test/book/16?parent=2
{
    "name": "book of history",
    "category": "historical",
    "publisher": "publisher2"
}

POST /test/book/20?parent=2
{
    "name": "second fictional book",
    "category": "Fiction",
    "publisher": "publisher2"
}

下面的Java类执行3个查询:

  1. 搜索books标题中带有“ book”一词的所有内容,然后返回authors
  2. 搜索名称中所有authors带有“ jon doe”字样的内容,然后返回books
  3. 搜索books“ jane smith”写的且类型为Fiction的内容。

您可以从命令行运行该类,也可以将其导入Eclipse,然后右键单击该类,然后选择“运行方式>
Java应用程序”。(您需要在类路径中有Elasticsearch库。)

import java.util.concurrent.ExecutionException;

import org.elasticsearch.action.search.SearchRequestBuilder;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.Client;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.ImmutableSettings;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.InetSocketTransportAddress;
import org.elasticsearch.index.query.FilterBuilders;
import org.elasticsearch.index.query.HasChildQueryBuilder;
import org.elasticsearch.index.query.HasParentQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.TermFilterBuilder;

public class ParentChildQueryExample {

  public static void main(String args[]) throws InterruptedException, ExecutionException {

    //Set the Transport client which is used to communicate with your ES cluster. It is also possible to set this up using the Client Node.
    Settings settings = ImmutableSettings.settingsBuilder()
        .put("cluster.name", "elasticsearch").build();
    Client client = new TransportClient(settings)
        .addTransportAddress(new InetSocketTransportAddress(
        "localhost",
        9300));

    //create the searchRequestBuilder object.
    SearchRequestBuilder searchRequestBuilder = new SearchRequestBuilder(client).setIndices("test");

    //Query 1. Search on all books that have the term 'book' in the title and return the 'authors'.
    HasChildQueryBuilder bookNameQuery = QueryBuilders.hasChildQuery("book", QueryBuilders.matchQuery("name", "book"));
    System.out.println("Exectuing Query 1");
    SearchResponse searchResponse1 = searchRequestBuilder.setQuery(bookNameQuery).execute().actionGet();
    System.out.println("There were " + searchResponse1.getHits().getTotalHits()  + " results found for Query 1.");
    System.out.println(searchResponse1.toString());
    System.out.println();

    //Query 2. Search on all authors that have the terms 'jon doe' in the name and return the 'books'.
    HasParentQueryBuilder authorNameQuery = QueryBuilders.hasParentQuery("author", QueryBuilders.matchQuery("name", "jon doe"));
    System.out.println("Exectuing Query 2");
    SearchResponse searchResponse2 = searchRequestBuilder.setQuery(authorNameQuery).execute().actionGet();
    System.out.println("There were " + searchResponse2.getHits().getTotalHits()  + " results found for Query 2.");
    System.out.println(searchResponse2.toString());
    System.out.println();

    //Query 3. Search for books written by 'jane smith' and type Fiction.
    TermFilterBuilder termFilter = FilterBuilders.termFilter("category.raw", "Fiction");
    HasParentQueryBuilder authorNameQuery2 = QueryBuilders.hasParentQuery("author", QueryBuilders.matchQuery("name", "jane smith"));
    SearchResponse searchResponse3 = searchRequestBuilder.setQuery(QueryBuilders.filteredQuery(authorNameQuery2, termFilter)).execute().actionGet();
    System.out.println("There were " + searchResponse3.getHits().getTotalHits()  + " results found for Query 3.");
    System.out.println(searchResponse3.toString());
    System.out.println();
  }
}
2020-06-22