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Spring Boot + Spring Data + Elasticsearch实例

在本文中，我们将讨论“如何创建Spring Boot + Spring Data + Elasticsearch范例”。

本文中使用的工具：

Spring Boot 1.5.1.RELEASE
Spring Boot Starter Data Elasticsearch 1.5.1.RELEASE
Spring Data Elasticsearch 2.10.RELEASE
Elasticsearch 2.4.4
Maven
Java 8

注意

SpringBoot 1.5.1.RELEASE和Spring Data Elasticsearch 2.10.RELEASE仅支持ElasticSearch 2.4.0。他们不支持最新版本的ElasticSearch 5.x版本。

另附：目前spring boot借助spring data可以操作es。但是版本上有严格的要求。（此句非原文，减少踩坑）

1.项目结构

一个标准的Maven项目结构。

Spring Boot + Spring Data + Elasticsearch实例

2.项目依赖

为Spring Data ElasticSearch application配置spring-boot-starter-data-elasticsearch。

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
         http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <artifactId>springboot-springdata-elasticsearch-example</artifactId>
    <packaging>jar</packaging>
    <url>https://www.mkyong.com</url>
    <version>1.0</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.1.RELEASE</version>
    </parent>

    <properties>
        <java.version>1.8</java.version>
    </properties>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <!-- Runtime, for Embedded Elasticsearch,
            comment this if connect to external elastic search server-->
        <dependency>
            <groupId>net.java.dev.jna</groupId>
            <artifactId>jna</artifactId>
            <scope>runtime</scope>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <!-- Package as an executable jar/war -->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

检查项目依赖关系：

$ mvn dependency:tree
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building springboot-springdata-elasticsearch-example 1.0
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-dependency-plugin:2.10:tree (default-cli) @ springboot-springdata-elasticsearch-example ---
[INFO] org.springframework.boot:springboot-springdata-elasticsearch-example:jar:1.0
[INFO] +- org.springframework.boot:spring-boot-starter-data-elasticsearch:jar:1.5.1.RELEASE:compile
[INFO] |  +- org.springframework.boot:spring-boot-starter:jar:1.5.1.RELEASE:compile
[INFO] |  |  +- org.springframework.boot:spring-boot:jar:1.5.1.RELEASE:compile
[INFO] |  |  +- org.springframework.boot:spring-boot-autoconfigure:jar:1.5.1.RELEASE:compile
[INFO] |  |  +- org.springframework.boot:spring-boot-starter-logging:jar:1.5.1.RELEASE:compile
[INFO] |  |  |  +- ch.qos.logback:logback-classic:jar:1.1.9:compile
[INFO] |  |  |  |  /- ch.qos.logback:logback-core:jar:1.1.9:compile
[INFO] |  |  |  +- org.slf4j:jul-to-slf4j:jar:1.7.22:compile
[INFO] |  |  |  /- org.slf4j:log4j-over-slf4j:jar:1.7.22:compile
[INFO] |  |  /- org.yaml:snakeyaml:jar:1.17:compile
[INFO] |  /- org.springframework.data:spring-data-elasticsearch:jar:2.1.0.RELEASE:compile
[INFO] |     +- org.springframework:spring-context:jar:4.3.6.RELEASE:compile
[INFO] |     |  +- org.springframework:spring-aop:jar:4.3.6.RELEASE:compile
[INFO] |     |  +- org.springframework:spring-beans:jar:4.3.6.RELEASE:compile
[INFO] |     |  /- org.springframework:spring-expression:jar:4.3.6.RELEASE:compile
[INFO] |     +- org.springframework:spring-tx:jar:4.3.6.RELEASE:compile
[INFO] |     +- org.springframework.data:spring-data-commons:jar:1.13.0.RELEASE:compile
[INFO] |     +- commons-lang:commons-lang:jar:2.6:compile
[INFO] |     +- joda-time:joda-time:jar:2.9.7:compile
[INFO] |     +- org.elasticsearch:elasticsearch:jar:2.4.4:compile
[INFO] |     |  +- org.apache.lucene:lucene-core:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-backward-codecs:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-analyzers-common:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-queries:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-memory:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-highlighter:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-queryparser:jar:5.5.2:compile
[INFO] |     |  |  /- org.apache.lucene:lucene-sandbox:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-suggest:jar:5.5.2:compile
[INFO] |     |  |  /- org.apache.lucene:lucene-misc:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-join:jar:5.5.2:compile
[INFO] |     |  |  /- org.apache.lucene:lucene-grouping:jar:5.5.2:compile
[INFO] |     |  +- org.apache.lucene:lucene-spatial:jar:5.5.2:compile
[INFO] |     |  |  +- org.apache.lucene:lucene-spatial3d:jar:5.5.2:compile
[INFO] |     |  |  /- com.spatial4j:spatial4j:jar:0.5:compile
[INFO] |     |  +- com.google.guava:guava:jar:18.0:compile
[INFO] |     |  +- org.elasticsearch:securesm:jar:1.0:compile
[INFO] |     |  +- com.carrotsearch:hppc:jar:0.7.1:compile
[INFO] |     |  +- com.fasterxml.jackson.dataformat:jackson-dataformat-smile:jar:2.8.6:compile
[INFO] |     |  +- com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:jar:2.8.6:compile
[INFO] |     |  +- com.fasterxml.jackson.dataformat:jackson-dataformat-cbor:jar:2.8.6:compile
[INFO] |     |  +- io.netty:netty:jar:3.10.6.Final:compile
[INFO] |     |  +- com.ning:compress-lzf:jar:1.0.2:compile
[INFO] |     |  +- com.tdunning:t-digest:jar:3.0:compile
[INFO] |     |  +- org.hdrhistogram:HdrHistogram:jar:2.1.6:compile
[INFO] |     |  +- commons-cli:commons-cli:jar:1.3.1:compile
[INFO] |     |  /- com.twitter:jsr166e:jar:1.1.0:compile
[INFO] |     +- com.fasterxml.jackson.core:jackson-core:jar:2.8.6:compile
[INFO] |     +- com.fasterxml.jackson.core:jackson-databind:jar:2.8.6:compile
[INFO] |     |  /- com.fasterxml.jackson.core:jackson-annotations:jar:2.8.0:compile
[INFO] |     +- org.slf4j:slf4j-api:jar:1.7.22:compile
[INFO] |     /- org.slf4j:jcl-over-slf4j:jar:1.7.22:compile
[INFO] +- org.springframework.boot:spring-boot-starter-test:jar:1.5.1.RELEASE:test
[INFO] |  +- org.springframework.boot:spring-boot-test:jar:1.5.1.RELEASE:test
[INFO] |  +- org.springframework.boot:spring-boot-test-autoconfigure:jar:1.5.1.RELEASE:test
[INFO] |  +- com.jayway.jsonpath:json-path:jar:2.2.0:test
[INFO] |  |  /- net.minidev:json-smart:jar:2.2.1:test
[INFO] |  |     /- net.minidev:accessors-smart:jar:1.1:test
[INFO] |  |        /- org.ow2.asm:asm:jar:5.0.3:test
[INFO] |  +- junit:junit:jar:4.12:test
[INFO] |  +- org.assertj:assertj-core:jar:2.6.0:test
[INFO] |  +- org.mockito:mockito-core:jar:1.10.19:test
[INFO] |  |  /- org.objenesis:objenesis:jar:2.1:test
[INFO] |  +- org.hamcrest:hamcrest-core:jar:1.3:test
[INFO] |  +- org.hamcrest:hamcrest-library:jar:1.3:test
[INFO] |  +- org.skyscreamer:jsonassert:jar:1.4.0:test
[INFO] |  |  /- com.vaadin.external.google:android-json:jar:0.0.20131108.vaadin1:test
[INFO] |  +- org.springframework:spring-core:jar:4.3.6.RELEASE:compile
[INFO] |  /- org.springframework:spring-test:jar:4.3.6.RELEASE:test
[INFO] /- net.java.dev.jna:jna:jar:4.2.2:runtime
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.867 s
[INFO] Finished at: 2017-03-14T19:55:41+08:00
[INFO] Final Memory: 27M/437M
[INFO] ------------------------------------------------------------------------

3. Spring Data ElasticSearch应用程序

现在开始我们的Spring Boot + Spring Data + Elasticsearch实例：

3.1，为我们的项目开发model类

Book.java

package com.mkyong.book.model;

import org.springframework.data.annotation.Id;
import org.springframework.data.elasticsearch.annotations.Document;

@Document(indexName = "mkyong", type = "books")
public class Book {

    @Id
    private String id;
    private String title;
    private String author;
    private String releaseDate;

    public Book() {
    }

    public Book(String id, String title, String author, String releaseDate) {
        this.id = id;
        this.title = title;
        this.author = author;
        this.releaseDate = releaseDate;
    }

    //getters and setters

    @Override
    public String toString() {
        return "Book{" +
                "id='" + id + '/'' +
                ", title='" + title + '/'' +
                ", author='" + author + '/'' +
                ", releaseDate='" + releaseDate + '/'' +
                '}';
    }
}

3.2，为我们的项目开发Elasticsearch存储库

BookRepository.java

package com.mkyong.book.repository;

import com.mkyong.book.model.Book;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.elasticsearch.repository.ElasticsearchRepository;

import java.util.List;

public interface BookRepository extends ElasticsearchRepository<Book, String> {

    Page<Book> findByAuthor(String author, Pageable pageable);

    List<Book> findByTitle(String title);

}

3.3，为我们的项目开发service层

BookService.java

package com.mkyong.book.service;

import com.mkyong.book.model.Book;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;

import java.util.List;

public interface BookService {

    Book save(Book book);

    void delete(Book book);

    Book findOne(String id);

    Iterable<Book> findAll();

    Page<Book> findByAuthor(String author, PageRequest pageRequest);

    List<Book> findByTitle(String title);

}

BookServiceImpl.java

package com.mkyong.book.service;

import com.mkyong.book.model.Book;
import com.mkyong.book.repository.BookRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class BookServiceImpl implements BookService {

    private BookRepository bookRepository;

  @Autowired
    public void setBookRepository(BookRepository bookRepository) {
        this.bookRepository = bookRepository;
    }


    public Book save(Book book) {
        return bookRepository.save(book);
    }

    public void delete(Book book) {
        bookRepository.delete(book);
    }

    public Book findOne(String id) {
        return bookRepository.findOne(id);
    }

    public Iterable<Book> findAll() {
        return bookRepository.findAll();
    }

    public Page<Book> findByAuthor(String author, PageRequest pageRequest) {
        return bookRepository.findByAuthor(author, pageRequest);
    }

    public List<Book> findByTitle(String title) {
        return bookRepository.findByTitle(title);
    }

}

3.4，在application.properties中配置Elasticsearch属性

application.properties

elasticsearch.clustername = mkyong-cluster
elasticsearch.host = localhost
elasticsearch.port = 9300

#
# Home directory of the embedded Elasticsearch instance. Default to the
# current working directory.
#
#spring.data.elasticsearch.properties.path.home=target/elastic-embedded
#spring.data.elasticsearch.properties.transport.tcp.connect_timeout=60s

3.5，为SpringBoot配置。TransportClient连接ElasticSearch

MkyongElasticsearchConfiguration.java

package com.mkyong;

import org.elasticsearch.client.Client;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.InetSocketTransportAddress;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.elasticsearch.core.ElasticsearchOperations;
import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
import org.springframework.data.elasticsearch.repository.config.EnableElasticsearchRepositories;

import java.net.InetAddress;

@Configuration
@EnableElasticsearchRepositories(basePackages = "com.mkyong.book.repository")
public class EsConfig {

    @Value("${elasticsearch.host}")
    private String EsHost;

    @Value("${elasticsearch.port}")
    private int EsPort;

    @Value("${elasticsearch.clustername}")
    private String EsClusterName;

    @Bean
    public Client client() throws Exception {

        Settings esSettings = Settings.settingsBuilder()
                .put("cluster.name", EsClusterName)
                .build();

        //https://www.elastic.co/guide/en/elasticsearch/guide/current/_transport_client_versus_node_client.html
        return TransportClient.builder()
                .settings(esSettings)
                .build()
                .addTransportAddress(
          new InetSocketTransportAddress(InetAddress.getByName(EsHost), EsPort));
    }

    @Bean
    public ElasticsearchOperations elasticsearchTemplate() throws Exception {
        return new ElasticsearchTemplate(client());
    }

    //Embedded Elasticsearch Server
    /*@Bean
    public ElasticsearchOperations elasticsearchTemplate() {
        return new ElasticsearchTemplate(nodeBuilder().local(true).node().client());
    }*/

}

4.开发测试应用程序

让我们开发一个测试应用程序来测试我们的代码。

BookServiceTest.java

package com.mkyong;

import com.mkyong.book.model.Book;
import com.mkyong.book.service.BookService;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
import org.springframework.test.context.junit4.SpringRunner;

import java.util.ArrayList;
import java.util.List;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.Assert.*;

@RunWith(SpringRunner.class)
@SpringBootTest(classes = Application.class)
public class BookServiceTest {

    @Autowired
    private BookService bookService;

    @Autowired
    private ElasticsearchTemplate esTemplate;

    @Before
    public void before() {
        esTemplate.deleteIndex(Book.class);
        esTemplate.createIndex(Book.class);
        esTemplate.putMapping(Book.class);
        esTemplate.refresh(Book.class);
    }

    @Test
    public void testSave() {

        Book book = new Book("1001", "Elasticsearch Basics", "Rambabu Posa", "23-FEB-2017");
        Book testBook = bookService.save(book);

        assertNotNull(testBook.getId());
        assertEquals(testBook.getTitle(), book.getTitle());
        assertEquals(testBook.getAuthor(), book.getAuthor());
        assertEquals(testBook.getReleaseDate(), book.getReleaseDate());

    }

    @Test
    public void testFindOne() {

        Book book = new Book("1001", "Elasticsearch Basics", "Rambabu Posa", "23-FEB-2017");
        bookService.save(book);

        Book testBook = bookService.findOne(book.getId());

        assertNotNull(testBook.getId());
        assertEquals(testBook.getTitle(), book.getTitle());
        assertEquals(testBook.getAuthor(), book.getAuthor());
        assertEquals(testBook.getReleaseDate(), book.getReleaseDate());

    }

    @Test
    public void testFindByTitle() {

        Book book = new Book("1001", "Elasticsearch Basics", "Rambabu Posa", "23-FEB-2017");
        bookService.save(book);

        List<Book> byTitle = bookService.findByTitle(book.getTitle());
        assertThat(byTitle.size(), is(1));
    }

    @Test
    public void testFindByAuthor() {

        List<Book> bookList = new ArrayList<>();

        bookList.add(new Book("1001", "Elasticsearch Basics", "Rambabu Posa", "23-FEB-2017"));
        bookList.add(new Book("1002", "Apache Lucene Basics", "Rambabu Posa", "13-MAR-2017"));
        bookList.add(new Book("1003", "Apache Solr Basics", "Rambabu Posa", "21-MAR-2017"));
        bookList.add(new Book("1007", "Spring Data + ElasticSearch", "Rambabu Posa", "01-APR-2017"));
        bookList.add(new Book("1008", "Spring Boot + MongoDB", "Mkyong", "25-FEB-2017"));

        for (Book book : bookList) {
            bookService.save(book);
        }

        Page<Book> byAuthor = bookService.findByAuthor("Rambabu Posa", new PageRequest(0, 10));
        assertThat(byAuthor.getTotalElements(), is(4L));

        Page<Book> byAuthor2 = bookService.findByAuthor("Mkyong", new PageRequest(0, 10));
        assertThat(byAuthor2.getTotalElements(), is(1L));

    }

    @Test
    public void testDelete() {

        Book book = new Book("1001", "Elasticsearch Basics", "Rambabu Posa", "23-FEB-2017");
        bookService.save(book);
        bookService.delete(book);
        Book testBook = bookService.findOne(book.getId());
        assertNull(testBook);
    }

}

5.运行Spring Boot Application

5.1要运行这个演示，我们应该按照以下这些步骤：

1、安装Java并设置JAVA_HOME和PATH变量。

2、安装Maven。

3、安装Elasticsearch 2.4.0
这里做一个假设路径：ELASTICSEARCH_HOME = C：/ elasticsearch-2.4.0

4、配置ElasticSearch
打开$ {ELASTICSEARCH_HOME} / config / elasticsearch.yml并添加以下配置

cluster.name: mkyong-cluster

5、启动Elasticsearch实例

5.2运行Spring Boot Application，它会将3个book对象插入到Elastic Server中。

Application.java

package com.mkyong;

import com.mkyong.book.model.Book;
import com.mkyong.book.service.BookService;
import org.elasticsearch.client.Client;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.elasticsearch.core.ElasticsearchOperations;

import java.util.Map;

@SpringBootApplication
public class Application implements CommandLineRunner {

    @Autowired
    private ElasticsearchOperations es;

    @Autowired
    private BookService bookService;

    public static void main(String args[]) {
        SpringApplication.run(Application.class, args);
    }

    @Override
    public void run(String... args) throws Exception {

        printElasticSearchInfo();

        bookService.save(new Book("1001", "Elasticsearch Basics", "Rambabu Posa", "23-FEB-2017"));
        bookService.save(new Book("1002", "Apache Lucene Basics", "Rambabu Posa", "13-MAR-2017"));
        bookService.save(new Book("1003", "Apache Solr Basics", "Rambabu Posa", "21-MAR-2017"));

        //fuzzey search
        Page<Book> books = bookService.findByAuthor("Rambabu", new PageRequest(0, 10));

        //List<Book> books = bookService.findByTitle("Elasticsearch Basics");

        books.forEach(x -> System.out.println(x));


    }

    //useful for debug, print elastic search details
    private void printElasticSearchInfo() {

        System.out.println("--ElasticSearch--");
        Client client = es.getClient();
        Map<String, String> asMap = client.settings().getAsMap();

        asMap.forEach((k, v) -> {
            System.out.println(k + " = " + v);
        });
        System.out.println("--ElasticSearch--");
    }

}

输出结果：

.   ____          _            __ _ _
 /// / ___'_ __ _ _(_)_ __  __ _ / / / /
( ( )/___ | '_ | '_| | '_ // _` | / / / /
 ///  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_/__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v1.5.1.RELEASE)

//...
--ElasticSearch--
client.type = transport
cluster.name = mkyong-cluster
name = Baal
network.server = false
node.client = true
transport.ping_schedule = 5s
--ElasticSearch--
Book{id='1001', title='Elasticsearch Basics', author='Rambabu Posa', releaseDate='23-FEB-2017'}
Book{id='1002', title='Apache Lucene Basics', author='Rambabu Posa', releaseDate='13-MAR-2017'}
Book{id='1003', title='Apache Solr Basics', author='Rambabu Posa', releaseDate='21-MAR-2017'}
//...

当我们运行应用程序时，我们的数据存储在 $ {ELASTICSEARCH_HOME} / data / mkyong-cluster 中了。

5.3 Maven打包一下并且运行它。

运行结果：

$ mvn package
$ java -jar target/springboot-springdata-elasticsearch-example-1.0.jar

5.4用cURL工具测试一下。

运行结果：

C:/curl-7.53.1/bin>curl "http://localhost:9200/mkyong/books/_search?pretty=true"
{
  "took" : 3,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 3,
    "max_score" : 1.0,
    "hits" : [ {
      "_index" : "mkyong",
      "_type" : "books",
      "_id" : "1001",
      "_score" : 1.0,
      "_source" : {
        "id" : "1001",
        "title" : "Elasticsearch Basics",
        "author" : "Rambabu Posa",
        "releaseDate" : "23-FEB-2017"
      }
    }, {
      "_index" : "mkyong",
      "_type" : "books",
      "_id" : "1002",
      "_score" : 1.0,
      "_source" : {
        "id" : "1002",
        "title" : "Apache Lucene Basics",
        "author" : "Rambabu Posa",
        "releaseDate" : "13-MAR-2017"
      }
    }, {
      "_index" : "mkyong",
      "_type" : "books",
      "_id" : "1003",
      "_score" : 1.0,
      "_source" : {
        "id" : "1003",
        "title" : "Apache Solr Basics",
        "author" : "Rambabu Posa",
        "releaseDate" : "21-MAR-2017"
      }
    } ]
  }
}

运行结果：

C:/curl-7.53.1/bin>curl "http://localhost:9200/mkyong/books/_search?q=_id:1003&pretty=true"
{
  "took" : 3,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 1,
    "max_score" : 1.0,
    "hits" : [ {
      "_index" : "mkyong",
      "_type" : "books",
      "_id" : "1003",
      "_score" : 1.0,
      "_source" : {
        "id" : "1003",
        "title" : "Apache Solr Basics",
        "author" : "Rambabu Posa",
        "releaseDate" : "21-MAR-2017"
      }
    } ]
  }
}