使用 java 连接 Elasticsearch

Question

我是 java 的新手，来自 python。我知道有很多答案可以将 ElasticSearch 与 java 联系起来。但是我很难理解，有些已经过时了。在 python 中，我可以轻松导入 elasticsearch 模块并连接到它。

这是 python 中的代码：

from elasticsearch import Elasticsearch
es = Elasticsearch('localhost', port=9200, http_auth=('username', 'password'), scheme="http")

但是在 java 中，我在 pom.xml 中包含了 elasticsearch maven 依赖项。我想连接到 elasticsearch。我开始知道 RestHighLevelClient 可以胜任这项工作。我找到了这段代码。但是不知道如何让它连接到Elastic Search。

public RestHighLevelClient createESRestClient() {
    CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
    credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(esUserName, esPassword));

    RestClientBuilder restClientBuilder = RestClient
            .builder(new HttpHost(esRestclientHost, 9200, "http"));
    // Use this one if your ElasticSearch server is setup to use username & password authentication
    if (esAuthentication) {
        restClientBuilder.setHttpClientConfigCallback(h -> h.setDefaultCredentialsProvider(credentialsProvider));
    }

    return new RestHighLevelClient(restClientBuilder);
}

任何人都可以帮助我或向我展示一些示例代码以通过 java 连接 Elastic Search。在python中，分两行完成。帮我 java.

Answer 1

对于当前版本 Java REST Client 版本 7.5，请按照 ElasticSearch Client 中的说明进行操作：

RestHighLevelClient client = new RestHighLevelClient(
        RestClient.builder(
                new HttpHost("localhost", 9200, "http"),
                new HttpHost("localhost", 9201, "http")));

Maven repository，ElasticSearch 客户端：

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.5.2</version>
</dependency>

所有API功能都在客户网站指定：搜索、多搜索、索引等

"Java Low Level REST Client" 基本身份验证定义 here:

final CredentialsProvider credentialsProvider =
    new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY,
    new UsernamePasswordCredentials("user", "password"));

RestClientBuilder builder = RestClient.builder(
    new HttpHost("localhost", 9200))
    .setHttpClientConfigCallback(new HttpClientConfigCallback() {
        @Override
        public HttpAsyncClientBuilder customizeHttpClient(
                HttpAsyncClientBuilder httpClientBuilder) {
            return httpClientBuilder
                .setDefaultCredentialsProvider(credentialsProvider);
        }
    });

Answer 2

要使用 java 连接 elasticsearch，您可以使用以下代码：

public class ElasticsearchClient {
//private static final Logger log = LoggerFactory.getLogger(ElasticsearchClient.class);
private final RestHighLevelClient client;

public ElasticsearchClient(ElasticsearchConfig elasticsearchConfig) {
    client = new RestHighLevelClient(RestClient.builder(new HttpHost(elasticsearchConfig.getHost(),
            elasticsearchConfig.getPort(), "http")));
}
}

elasticsearch配置：

host: localhost

port: 9200

更多信息您可以查看this and this。

您甚至可以按照此 documentation

中的说明进行操作

你需要在pom.xml

中添加这个依赖

<dependency>
        <groupId>org.elasticsearch.client</groupId>
        <artifactId>elasticsearch-rest-high-level-client</artifactId>
        <version>${es.client.version}</version>
</dependency>

更新 1

为了在代码本身中添加主机和端口，您可以使用下面提到的代码，而不是单独的配置文件：

public class ElasticsearchClient {
private static final Logger log = LoggerFactory.getLogger(ElasticsearchClient.class);
private final RestHighLevelClient client;


public ElasticsearchClient(ElasticsearchConfig elasticsearchConfig) {
    client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
}

使用 java 连接 Elasticsearch

Connect Elasticsearch using java

java

elasticsearch

resthighlevelclient