「Elasticsearch」SpringBoot快速集成ES

Elastic Search 的底层是开源库 Lucene。但是Lucene的使用门槛比较高，必须自己写代码去调用它的接口。而Elastic Search的出现正是为了解决了这个问题，它是 Lucene 的封装，提供了 REST API 的操作接口，我们可以开箱即用。

环境

• JDK版本：8
• SpringBoot:2.x
• ES版本：7.1.1

  依赖

  <!--   集成es client，并排除低版本依赖(5.6)     -->
  <dependency>
  	<groupId>org.elasticsearch.client</groupId>
  	<artifactId>elasticsearch-rest-high-level-client</artifactId>
  	<version>7.1.1</version>
  	<exclusions>
  		<exclusion>
  			<groupId>org.elasticsearch</groupId>
  			<artifactId>elasticsearch</artifactId>
  		</exclusion>
  		<exclusion>
  			<groupId>org.elasticsearch.client</groupId>
  			<artifactId>elasticsearch-rest-client</artifactId>
  		</exclusion>
  	</exclusions>
  </dependency>
  <dependency>
  	<groupId>org.elasticsearch.client</groupId>
  	<artifactId>elasticsearch-rest-client</artifactId>
  	<version>7.1.1</version>
  </dependency>
  <dependency>
  	<groupId>org.elasticsearch</groupId>
  	<artifactId>elasticsearch</artifactId>
  	<version>7.1.1</version>
  </dependency>

  配置

  使用配置类配置，可以参考如下所示：
  先创建一个builder，用于初始化ES client

  public class EsClientBuilder {
      private int connectTimeoutMillis = 1000;
      private int socketTimeoutMillis = 30000;
      private int connectionRequestTimeoutMillis = 500;
      private int maxConnectPerRoute = 10;
      private int maxConnectTotal = 30;
  
      private final List<HttpHost> httpHosts;
  
  
      private EsClientBuilder(List<HttpHost> httpHosts) {
          this.httpHosts = httpHosts;
      }
  
  
      public EsClientBuilder setConnectTimeoutMillis(int connectTimeoutMillis) {
          this.connectTimeoutMillis = connectTimeoutMillis;
          return this;
      }
  
      public EsClientBuilder setSocketTimeoutMillis(int socketTimeoutMillis) {
          this.socketTimeoutMillis = socketTimeoutMillis;
          return this;
      }
  
      public EsClientBuilder setConnectionRequestTimeoutMillis(int connectionRequestTimeoutMillis) {
          this.connectionRequestTimeoutMillis = connectionRequestTimeoutMillis;
          return this;
      }
  
      public EsClientBuilder setMaxConnectPerRoute(int maxConnectPerRoute) {
          this.maxConnectPerRoute = maxConnectPerRoute;
          return this;
      }
  
      public EsClientBuilder setMaxConnectTotal(int maxConnectTotal) {
          this.maxConnectTotal = maxConnectTotal;
          return this;
      }
  
  
      public static EsClientBuilder build(List<HttpHost> httpHosts) {
          return new EsClientBuilder(httpHosts);
      }
  
  
      public RestHighLevelClient create() {
  
          HttpHost[] httpHostArr = httpHosts.toArray(new HttpHost[0]);
          RestClientBuilder builder = RestClient.builder(httpHostArr);
  
          builder.setRequestConfigCallback(requestConfigBuilder -> {
              requestConfigBuilder.setConnectTimeout(connectTimeoutMillis);
              requestConfigBuilder.setSocketTimeout(socketTimeoutMillis);
              requestConfigBuilder.setConnectionRequestTimeout(connectionRequestTimeoutMillis);
              return requestConfigBuilder;
          });
  
          builder.setHttpClientConfigCallback(httpClientBuilder -> {
              httpClientBuilder.setMaxConnTotal(maxConnectTotal);
              httpClientBuilder.setMaxConnPerRoute(maxConnectPerRoute);
              return httpClientBuilder;
          });
  
          return new RestHighLevelClient(builder);
      }
  }

  再交给spring容器管理：

  @Configuration
  public class ESConfig {
      @Value("${elasticsearch.nodes}")
      private List<String> nodes;
  
      @Value("${elasticsearch.schema}")
      private String schema;
  
      @Value("${elasticsearch.max-connect-total}")
      private Integer maxConnectTotal;
  
      @Value("${elasticsearch.max-connect-per-route}")
      private Integer maxConnectPerRoute;
  
      @Value("${elasticsearch.connection-request-timeout-millis}")
      private Integer connectionRequestTimeoutMillis;
  
      @Value("${elasticsearch.socket-timeout-millis}")
      private Integer socketTimeoutMillis;
  
      @Value("${elasticsearch.connect-timeout-millis}")
      private Integer connectTimeoutMillis;
  
      @Bean
      public RestHighLevelClient getRestHighLevelClient() {
          List<HttpHost> httpHosts = new ArrayList<>();
          for (String node : nodes) {
              try {
                  String[] parts = StringUtils.split(node, ":");
                  Assert.notNull(parts,"Must defined");
                  Assert.state(parts.length == 2, "Must be defined as 'host:port'");
                  httpHosts.add(new HttpHost(parts[0], Integer.parseInt(parts[1]), schema));
              } catch (RuntimeException ex) {
                  throw new IllegalStateException(
                          "Invalid ES nodes " + "property '" + node + "'", ex);
              }
          }
  
          return EsClientBuilder.build(httpHosts)
                  .setConnectionRequestTimeoutMillis(connectionRequestTimeoutMillis)
                  .setConnectTimeoutMillis(connectTimeoutMillis)
                  .setSocketTimeoutMillis(socketTimeoutMillis)
                  .setMaxConnectTotal(maxConnectTotal)
                  .setMaxConnectPerRoute(maxConnectPerRoute)
                  .create();
      }
  }

  再配置一下常用的配置：

  #配置es
  elasticsearch:
    #  如果是cluster，application.yml的nodes设置多个ip:host逗号隔开即可。
    nodes: 127.0.0.1:9200
    schema: http
    max-connect-total: 50
    max-connect-per-route: 10
    connection-request-timeout-millis: 500
    socket-timeout-millis: 30000
    connect-timeout-millis: 1000

  使用

  接下来我们测试一下配置是否生效，一个简单的验证送给大家，如下所示：

  @Autowired
      private RestHighLevelClient client;
      @Test
      public void test() throws IOException {
          MainResponse info = client.info(RequestOptions.DEFAULT);
          System.out.println(info.toString());
      }

  配置生效的话，就会返回Elastic Search的配置信息：包含当前节点、集群、版本等信息。
  SpringBoot集成ES至此结束。