java - 从 ElasticSearch 中的索引中删除多个文档，其中一个项目的值为 - 7.8 版

Question

我在 elsticsearch 中的文档如下

    "hits" : [
      {
        "_index" : "MyIndex",
        "_type" : "_doc",
        "_id" : "Lxh7THMBycWRIeJFdwbZ",
        "_score" : 1.0,
        "_source" : {
          "@timestamp" : "2020-07-14T13:10:26.087+0430",
          "message" : "elk: customer inserted: id=5",
          "traceId" : "ABC",
          "severity" : "INFO",
          "thread" : "http-nio-8095-exec-2"
        }
      }
]

我想用 java 代码删除一个索引中的“traceId”：“ABC”的所有文档。我使用 Elasticsearch 7.8，我的客户端是 RestHighLevelClient。请指导我。

Answer 1

下面的示例代码应该会有所帮助。您可以参考下面的链接来浏览 API 并了解需要分步执行的操作。

基本上，通过 Java 发送的每个请求都包含以下两部分。

• 每个发送到 elasticsearch 的请求都类似于 HttpClient ，即High Level Rest Client。
• API 特定查询，在我们的例子中是按查询删除

至于您的示例，请注意，我假设这traceId.keyword是类型字段，keyword因此我使用的是TermBuilderTerm Query。如果它是text我Match Query在评论中提到的类型，您将不得不使用它。

示例代码

import java.io.IOException;

import org.apache.http.HttpHost;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.TermQueryBuilder;
import org.elasticsearch.index.reindex.BulkByScrollResponse;
import org.elasticsearch.index.reindex.DeleteByQueryRequest;

public class DeleteBasedOnQuery {

    public static void main(String[] args) throws IOException {

        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http")));

        deleteQueryUsingMatch(client);

        client.close();

    }
    
    private static void deleteQueryUsingMatch(RestHighLevelClient client) throws IOException {
        
        //Mention index name
        DeleteByQueryRequest request = new DeleteByQueryRequest("my_delete_index");
        request.setConflicts("proceed"); 
        request.setBatchSize(100);
        request.setRefresh(true); 
        
        //Term Query to Delete the document. Note the field name and value in below code
        request.setQuery(new TermQueryBuilder("traceId.keyword", "ABC"));
        
        //Match Query to Delete the Document
        //request.setQuery(QueryBuilders.matchQuery("traceID", "abc"));
        
        //Execute the request to delete based on above details
        BulkByScrollResponse bulkResponse = client.deleteByQuery(request, RequestOptions.DEFAULT);
        
        //By this time your delete query got executed and you have the response with you. 
        long totalDocs = bulkResponse.getTotal(); 
        long deletedDocs = bulkResponse.getDeleted(); 
        
        //Print the response details
        System.out.println("Total Docs Processed :: " +  totalDocs);
        System.out.println("Total Docs Deleted :: " +  deletedDocs);        
        
    }

}