使用DeleteByQueryAction删除ES指定ID文档遇类找不到错误

问题场景 #

尝试删除Elasticsearch中特定ID的文档，编写了如下Java代码：

// Create the low-level client
RestClient restClient = RestClient.builder( new HttpHost(hostName, portName)).build();
    
// Create the transport with a Jackson mapper
ElasticsearchTransport transport = new RestClientTransport(restClient, new JacksonJsonpMapper());

// And create the API client
ElasticsearchClient client = new ElasticsearchClient(transport);
    
public long delete( String indexName, String key, String value )
{   
    BulkByScrollResponse response =
    DeleteByQueryAction.INSTANCE.newRequestBuilder( client )
            .filter( QueryBuilders.matchQuery( key, value ) ) 
            .source( indexName )
            .refresh( true )
            .get();                                              
    logger.info( "Deleted " + response.getDeleted() + " element(s)!" );
        
    return response.getDeleted();
}

同时在pom.xml中引入了以下依赖：

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>transport</artifactId>
    <version>7.17.9</version>
</dependency>

运行时出现编译错误：

error: cannot find symbol
[ERROR] symbol: class ElasticsearchTransport

问题原因 #

ElasticsearchTransport和ElasticsearchClient属于Elasticsearch 7.x版本推出的新REST客户端（elasticsearch-java），而你引入的transport依赖是旧版TCP传输客户端的包，两者不兼容，导致找不到对应的类。

解决步骤 #

1. 替换pom依赖
   移除旧的transport依赖，添加新客户端的必要依赖：

<!-- Elasticsearch Java REST客户端核心包 -->
<dependency>
    <groupId>co.elastic.clients</groupId>
    <artifactId>elasticsearch-java</artifactId>
    <version>7.17.9</version>
</dependency>
<!-- 低级REST客户端依赖 -->
<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-client</artifactId>
    <version>7.17.9</version>
</dependency>

2. 修正代码实现
   旧代码中DeleteByQueryAction是旧版High Level Client的写法，和新客户端不兼容。如果是删除单个特定ID的文档，推荐使用更高效的单文档删除API：

import co.elastic.clients.elasticsearch.ElasticsearchClient;
import co.elastic.clients.elasticsearch.core.DeleteResponse;
import co.elastic.clients.elasticsearch.core.Refresh;
import co.elastic.clients.transport.ElasticsearchTransport;
import co.elastic.clients.transport.rest_client.RestClientTransport;
import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import com.fasterxml.jackson.databind.ObjectMapper;
import co.elastic.clients.json.jackson.JacksonJsonpMapper;

// 创建低级客户端
RestClient restClient = RestClient.builder(new HttpHost(hostName, portName)).build();

// 创建传输层，绑定Jackson映射器
ElasticsearchTransport transport = new RestClientTransport(
    restClient, new JacksonJsonpMapper(new ObjectMapper())
);

// 创建API客户端
ElasticsearchClient client = new ElasticsearchClient(transport);

public long deleteById(String indexName, String docId) throws IOException {
    DeleteResponse response = client.delete(d -> d
            .index(indexName)
            .id(docId)
            .refresh(Refresh.True)
    );
    // 判断是否删除成功
    long deletedCount = response.result() == co.elastic.clients.elasticsearch.core.Result.Deleted ? 1 : 0;
    logger.info("Deleted " + deletedCount + " element(s)!");
    return deletedCount;
}

如果需要通过**匹配字段（比如按ID字段批量删除）**使用DeleteByQuery，新客户端的写法如下：

public long deleteByQuery(String indexName, String key, String value) throws IOException {
    DeleteByQueryResponse response = client.deleteByQuery(d -> d
            .index(indexName)
            .query(q -> q
                    .match(m -> m
                            .field(key)
                            .query(value)
                    )
            )
            .refresh(Refresh.True)
    );
    logger.info("Deleted " + response.deleted() + " element(s)!");
    return response.deleted();
}

内容的提问来源于stack exchange，提问作者Vio