Java Elasticsearch 连接配置

本节主要讲解Java Elasticsearch RestHighLevelClient的配置详解。

RestHighLevelClient常用配置如下：

• elasticsearch连接地址
• elasticsearch账号/密码
• Http请求头
• 连接超时
• 设置线程池大小

创建client

RestHighLevelClient 依赖 REST low-level client builder 进行配置，即依赖底层的RestClientBuilder对象进行参数设置

// 首先创建RestClientBuilder，后续章节通过RestClientBuilder对象进行参数配置。
RestClientBuilder restClientBuilder = RestClient.builder(
                new HttpHost("localhost", 9200, "http"), // 设置ES服务地址，支持多个
                new HttpHost("localhost", 9201, "http"));

// 创建RestHighLevelClient，请求都是通过RestHighLevelClient实例发出去的。
RestHighLevelClient client = new RestHighLevelClient(restClientBuilder);

配置ES账号密码

restClientBuilder.setHttpClientConfigCallback(new RestClientBuilder.HttpClientConfigCallback() {
        @Override
        public HttpAsyncClientBuilder customizeHttpClient(
                            HttpAsyncClientBuilder httpClientBuilder) {
              // 通过CredentialsProvider实例，配置账号和密码
              CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
              credentialsProvider.setCredentials(AuthScope.ANY,
                                new UsernamePasswordCredentials("user", "password"));
                        
               // 设置安全验证凭证
               return httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider);
                    }
                });

设置Http Header

// 创建header数组，可以设置多个header
Header[] defaultHeaders = new Header[]{new BasicHeader("header", "value")};
// 设置http header
restClientBuilder.setDefaultHeaders(defaultHeaders); 

Timeout设置

配置Elasticsearch连接超时时间

restClientBuilder.setRequestConfigCallback(
                new RestClientBuilder.RequestConfigCallback() {
                    @Override
                    public RequestConfig.Builder customizeRequestConfig(
                            RequestConfig.Builder requestConfigBuilder) {
                        return requestConfigBuilder
                                .setConnectTimeout(5000) // 设置连接超时时间，5秒
                                .setSocketTimeout(60000); // 设置请求超时时间，1分种
                    }
                });

设置线程池大小

restClientBuilder.setHttpClientConfigCallback(new RestClientBuilder.HttpClientConfigCallback() {
            @Override
            public HttpAsyncClientBuilder customizeHttpClient(
                    HttpAsyncClientBuilder httpClientBuilder) {
                return httpClientBuilder.setDefaultIOReactorConfig(
                        IOReactorConfig.custom()
                                .setIoThreadCount(10) // 设置线程数
                                .build());
            }
        });