How to configure a Spring Boot application to work with…

In order to integrate an Elasticsearch cluster into a Spring Boot project, you need to make the following configurations:

1. pom.xml is a file used for configuring and managing dependencies in a Java project.

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
</dependency>

1. properties file for an application
2. config file used to store application settings and configurations

spring.elasticsearch.rest.uris=http://localhost:9200,http://localhost:9201,http://localhost:9202

Alternatively, you can use YAML formatting for the configuration.

spring:
  elasticsearch:
    rest:
      uris: http://localhost:9200,http://localhost:9201,http://localhost:9202

1. properties file for an application
2. configuration file called application.yml

spring.elasticsearch.rest.max-connections=10
spring.elasticsearch.rest.max-per-route-connections=5

Alternatively, use configuration in YAML format.

spring:
  elasticsearch:
    rest:
      max-connections: 10
      max-per-route-connections: 5

1. Create a client for Elasticsearch: Create a RestHighLevelClient bean in the configuration class of Spring Boot to interact with Elasticsearch.

import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class ElasticsearchConfig {

    @Bean
    public RestHighLevelClient elasticsearchClient() {
        return new RestHighLevelClient(
                RestClient.builder(
                        new HttpHost("localhost", 9200, "http"),
                        new HttpHost("localhost", 9201, "http"),
                        new HttpHost("localhost", 9202, "http")
                )
        );
    }
}

Placing the above code in a class annotated with @Configuration will automatically register methods annotated with @Bean as beans in Spring Boot.

These are the configuration steps for integrating an Elasticsearch cluster in a Spring Boot project. You can make adjustments and optimizations according to your actual needs.