ElasticSearch 8 学习笔记总结
Posted IT_Holmes
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文章目录
一. ES8 的Java API 环境准备
ES8 废除了Type的概念。为了适应这种数据结构的改变，ES官方从1.7版本开始建议使用新的Elasticsearch Java Client。
搭建maven环境：
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
<elastic.version>8.6.2</elastic.version>
</properties>
<dependencies>
<dependency>
<groupId>org.elasticsearch.plugin</groupId>
<artifactId>x-pack-sql-jdbc</artifactId>
<version>8.6.2</version>
</dependency>
<dependency>
<groupId>co.elastic.clients</groupId>
<artifactId>elasticsearch-java</artifactId>
<version>$elastic.version</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.12.3</version>
</dependency>
<dependency>
<groupId>jakarta.json</groupId>
<artifactId>jakarta.json-api</artifactId>
<version>2.0.1</version>
</dependency>
</dependencies>
获取客户端对象：
因为，服务注册的是基于https的安全elasticsearch服务认证，所以，将之前的证书进行一个转换：
# 生成es-api-ca.crt证书，之前没有密码设置。
openssl pkcs12 -in elastic-stack-ca.p12 -clcerts -nokeys -out es-api-ca.crt
将生成的证书放到项目里面。
创建连接对象：
package com.itholmes.elasticsearch.api;
import co.elastic.clients.elasticsearch.ElasticsearchAsyncClient;
import co.elastic.clients.elasticsearch.ElasticsearchClient;
import co.elastic.clients.json.jackson.JacksonJsonpMapper;
import co.elastic.clients.transport.rest_client.RestClientTransport;
import org.apache.http.HttpHost;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.conn.ssl.NoopHostnameVerifier;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.nio.client.HttpAsyncClientBuilder;
import org.apache.http.ssl.SSLContextBuilder;
import org.apache.http.ssl.SSLContexts;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestClientBuilder;
import javax.net.ssl.SSLContext;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.security.KeyStore;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
public class ESClient
public static void main(String[] args) throws Exception
// 初始化ES服务器的连接
initESConnection();
public static void initESConnection() throws Exception
final BasicCredentialsProvider credentialsProvider = new BasicCredentialsProvider();
// 声明ES当前登录的账号密码
credentialsProvider.setCredentials(AuthScope.ANY,new UsernamePasswordCredentials("elastic","3j=JYpywv=jMtQB+XIXS"));
// 证书的路径
Path caCertificatePath = Paths.get("E:\\\\itholmes\\\\demo\\\\itholmes-es8\\\\certs\\\\es-api-ca.crt");
// x.509 , pkcs12都是 证书的算法
CertificateFactory factory = CertificateFactory.getInstance("x.509");
Certificate trustedCa;
try (InputStream is = Files.newInputStream(caCertificatePath))
trustedCa = factory.generateCertificate(is);
KeyStore trustStore = KeyStore.getInstance("pkcs12");
trustStore.load(null,null);
trustStore.setCertificateEntry("ca",trustedCa);
SSLContextBuilder sslContextBuilder = SSLContexts.custom()
.loadTrustMaterial(trustStore,null);
SSLContext sslContext = sslContextBuilder.build();
RestClientBuilder builder = RestClient.builder(new HttpHost("192.168.43.133", 9200, "https"))
.setHttpClientConfigCallback(new RestClientBuilder.HttpClientConfigCallback()
@Override
public HttpAsyncClientBuilder customizeHttpClient(HttpAsyncClientBuilder httpClientBuilder)
return httpClientBuilder.setSSLContext(sslContext).setSSLHostnameVerifier(NoopHostnameVerifier.INSTANCE)
.setDefaultCredentialsProvider(credentialsProvider);
);
// 创建客户端
RestClient restClient = builder.build();
// 通过客户端，创建传输对象
RestClientTransport transport = new RestClientTransport(restClient, new JacksonJsonpMapper());
// 同步客户端对象
ElasticsearchClient client = new ElasticsearchClient(transport);
// 异步客户端对象
ElasticsearchAsyncClient asyncClient = new ElasticsearchAsyncClient(transport);
// fixme 同步是需要关闭的，而异步是不需要关闭的。
transport.close();
二. ES8 的Java API 索引操作
ES Java的API相关操作：
- 采用构造器形式来创建所需要的对象。
- 通过lambda来创建。
对象形式操作：
package com.itholmes.elasticsearch.api;
import co.elastic.clients.elasticsearch.ElasticsearchAsyncClient;
import co.elastic.clients.elasticsearch.ElasticsearchClient;
import co.elastic.clients.elasticsearch.indices.*;
import co.elastic.clients.json.jackson.JacksonJsonpMapper;
import co.elastic.clients.transport.ElasticsearchTransport;
import co.elastic.clients.transport.rest_client.RestClientTransport;
import org.apache.http.HttpHost;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.conn.ssl.NoopHostnameVerifier;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.nio.client.HttpAsyncClientBuilder;
import org.apache.http.ssl.SSLContextBuilder;
import org.apache.http.ssl.SSLContexts;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestClientBuilder;
import javax.net.ssl.SSLContext;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.security.KeyStore;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
public class ESClient
private static ElasticsearchClient client;
private static ElasticsearchAsyncClient asyncClient;
private static ElasticsearchTransport transport;
public static final String INDEX_HOLMES = "itholmes";
public static void main(String[] args) throws Exception
// 初始化ES服务器的连接
initESConnection();
// 操作索引
operationIndex();
// 操作索引
private static void operationIndex() throws Exception
// 获取索引客户端对象
ElasticsearchIndicesClient indices = client.indices();
// 判断索引是否存在
ExistsRequest existsRequest = new ExistsRequest.Builder().index(INDEX_HOLMES).build();
final boolean flg = indices.exists(existsRequest).value();
if (flg)
System.out.println("索引" + INDEX_HOLMES + "已经存在！");
else
// 创建索引
// CreateIndexRequest构造方法已经私有化了，所以需要采用构建器方式来构建对象。ES的API对象基本上都采用构建器的方式创建对象。
CreateIndexRequest request = new CreateIndexRequest.Builder()
.index(INDEX_HOLMES)
.build();
final CreateIndexResponse createIndexResponse = indices.create(request);
System.out.println("创建索引的响应对象" + createIndexResponse);
// 查询索引
GetIndexRequest getIndexRequest = new GetIndexRequest.Builder().index(INDEX_HOLMES).build();
final GetIndexResponse getIndexResponse = indices.get(getIndexRequest);
// IndexState itholmes = getIndexResponse.get("itholmes");
System.out.println("查询的响应结果：" + getIndexResponse);
// 删除索引
DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest.Builder().index(INDEX_HOLMES).build();
DeleteIndexResponse delete = indices.delete(deleteIndexRequest);
System.out.println("索引删除成功：" + delete);
// fixme 同步是需要关闭的，而异步是不需要关闭的。
transport.close();
public static void initESConnection() throws Exception
final BasicCredentialsProvider credentialsProvider = new BasicCredentialsProvider();
// 声明ES当前登录的账号密码
credentialsProvider.setCredentials(AuthScope.ANY,new UsernamePasswordCredentials("elastic","3j=JYpywv=jMtQB+XIXS"));
// 证书的路径
Path caCertificatePath = Paths.get("E:\\\\itholmes\\\\demo\\\\itholmes-es8\\\\certs\\\\es-api-ca.crt");
// x.509 , pkcs12都是 证书的算法
CertificateFactory factory = CertificateFactory.getInstance("x.509");
Certificate trustedCa;
try (InputStream is = Files.newInputStream(caCertificatePath))
trustedCa = factory.generateCertificate(is);
KeyStore trustStore = KeyStore.getInstance("pkcs12");
trustStore.load(null,null);
trustStore.setCertificateEntry("ca",trustedCa);
SSLContextBuilder sslContextBuilder = SSLContexts.custom()
.loadTrustMaterial(trustStore,null);
SSLContext sslContext = sslContextBuilder.build();
RestClientBuilder builder = RestClient.builder(new HttpHost("192.168.43.133", 9200, "https"))
.setHttpClientConfigCallback(new RestClientBuilder.HttpClientConfigCallback()
@Override
public HttpAsyncClientBuilder customizeHttpClient(HttpAsyncClientBuilder httpClientBuilder)
return httpClientBuilder.setSSLContext(sslContext).setSSLHostnameVerifier(NoopHostnameVerifier.INSTANCE)
.setDefaultCredentialsProvider(credentialsProvider);
);
// 创建客户端
RestClient restClient = builder.build();
// 通过客户端，创建传输对象
transport = new RestClientTransport(restClient, new JacksonJsonpMapper());
// 同步客户端对象
client = new ElasticsearchClient(transport);
// 异步客户端对象
asyncClient = new ElasticsearchAsyncClient(transport);
lambda方式创建索引：（推荐使用，代码简洁）
package com.itholmes.elasticsearch.api;
import co.elastic.clients.elasticsearch.ElasticsearchAsyncClient;
import co.elastic.clients.elasticsearch.ElasticsearchClient;
import co.elastic.clients.elasticsearch.indices.*;
import co.elastic.clients.json.jackson.JacksonJsonpMapper;
import co.elastic.clients.transport.ElasticsearchTransport;
import co.elastic.clients.transport.rest_client.RestClientTransport;
import co.elastic.clients.util.ObjectBuilder;
import org.apache.http.HttpHost;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.conn.ssl.NoopHostnameVerifier;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.nio.client.HttpAsyncClientBuilder;
import org.apache.http.ssl.SSLContextBuilder;
import org.apache.http.ssl.SSLContexts;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestClientBuilder;
import javax.net.ssl.SSLContext;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.ElasticSearch相关概念总结