基于spring-boot使用elasticsearch Java API 客户端

1 简介

我当前使用的es版本是7.17.4，elasticsearch-rest-high-level-client在 7.15.0 中已弃用。不推荐使用高级 REST 客户端，取而代之的是 Java API 客户端 。
spring-boot-starter-data-elasticsearch 也不推荐，虽然基础操作简化了很多,但是一旦使用了es高级特性,那么就如同进入了地狱,同时elasticsearch更新太快了spring-boot-starter-data-elasticsearch的版本根本就赶不上,导致升级会出现很多问题

现在在es官网推荐我们现在使用 Elasticsearch Java API 客户端 这个是相当于直接使用elasticsearch自身的接口Api所以不存在升级不兼容的问题。

2 无密码的java api客户端

package com.meizu.car.appstore.configuration;

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.commons.lang3.StringUtils;
import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class EsClientConfig {

    @Value("${es.hosts.name}")
    private String hosts;

    /**
     * 解析配置的字符串，转为HttpHost对象数组, hosts example:   127.0.0.1:9200,127.0.0.1:9300
     *
     * @return
     */
    private HttpHost[] toHttpHost() {
        if (StringUtils.isEmpty(hosts)) {
            throw new RuntimeException("invalid elasticsearch configuration");
        }

        String[] hostArray = hosts.split(",");
        HttpHost[] httpHosts = new HttpHost[hostArray.length];
        HttpHost httpHost;
        for (int i = 0; i < hostArray.length; i++) {
            String[] strings = hostArray[i].split(":");
            httpHost = new HttpHost(strings[0], Integer.parseInt(strings[1]), "http");
            httpHosts[i] = httpHost;
        }

        return httpHosts;
    }

    @Bean
    public ElasticsearchClient elasticsearchClient() {
        HttpHost[] httpHosts = toHttpHost();
        RestClient restClient = RestClient.builder(httpHosts).build();
        RestClientTransport transport = new RestClientTransport(restClient, new JacksonJsonpMapper());
        return new ElasticsearchClient(transport);
    }

    @Bean
    public ElasticsearchAsyncClient elasticsearchAsyncClient() {
        HttpHost[] httpHosts = toHttpHost();
        RestClient restClient = RestClient.builder(httpHosts).build();
        RestClientTransport transport = new RestClientTransport(restClient, new JacksonJsonpMapper());
        return new ElasticsearchAsyncClient(transport);
    }

}

1 有密码的java api客户端初始化

package com.meizu.car.appstore.configuration;

import co.elastic.clients.elasticsearch.ElasticsearchAsyncClient;
import co.elastic.clients.elasticsearch.ElasticsearchClient;
import co.elastic.clients.json.jackson.JacksonJsonpMapper;
import co.elastic.clients.transport.ElasticsearchTransport;
import co.elastic.clients.transport.rest_client.RestClientTransport;
import org.apache.commons.lang3.StringUtils;
import org.apache.http.HttpHost;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.elasticsearch.client.RestClient;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class EsClientConfig {

    @Value("${spring.elasticsearch.uris}")
    private String hosts;

    @Value("${spring.elasticsearch.username}")
    private String username;

    @Value("${spring.elasticsearch.password}")
    private String password;

    /**
     * 解析配置的字符串，转为HttpHost对象数组, hosts example:   127.0.0.1:9200,127.0.0.1:9300
     *
     * @return
     */
    private HttpHost[] toHttpHost() {
        if (StringUtils.isEmpty(hosts)) {
            throw new RuntimeException("invalid elasticsearch configuration");
        }

        String[] hostArray = hosts.split(",");
        HttpHost[] httpHosts = new HttpHost[hostArray.length];
        HttpHost httpHost;
        for (int i = 0; i < hostArray.length; i++) {
            String[] strings = hostArray[i].split(":");
            httpHost = new HttpHost(strings[0], Integer.parseInt(strings[1]), "http");
            httpHosts[i] = httpHost;
        }

        return httpHosts;
    }

    @Bean
    public ElasticsearchClient elasticsearchClient() {
        HttpHost[] httpHosts = toHttpHost();
        final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
        credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(username, password));
        RestClient restClient = RestClient.builder(httpHosts).setHttpClientConfigCallback(httpClientBuilder -> httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider)).build();
        ElasticsearchTransport transport = new RestClientTransport(restClient, new JacksonJsonpMapper());
        return new ElasticsearchClient(transport);
    }

    @Bean
    public ElasticsearchAsyncClient elasticsearchAsyncClient() {
        HttpHost[] httpHosts = toHttpHost();
        final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
        credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(username, password));
        RestClient restClient = RestClient.builder(httpHosts).setHttpClientConfigCallback(httpClientBuilder -> httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider)).build();
        ElasticsearchTransport transport = new RestClientTransport(restClient, new JacksonJsonpMapper());
        return new ElasticsearchAsyncClient(transport);
    }

}

参考文献：

1. Elasticsearch Java Client （github）
2. Configure security for the Elastic Stack edit
3. logstash配置security
4. Elasticsearch Java 客户端演进历史和选型指南
5. springboot版本与elastic版本强制关联关系
6. java与es8实战之四：SpringBoot应用中操作es8(无安全检查)
7. elasticsearch设置密码及Java密码连接
8. java与es8实战之五：SpringBoot应用中操作es8(带安全检查：https、账号密码、API Key)
9. springboo整合elasticSearch8 java client api(带密码 or 不带密码的配置)
10. es官网Configuring basic authentication
11. 官方java api 接口文档
12. SpringBoot-ElasticSearch8 使用
13. SpringBoot-starter-data整合Elasticsearch