[转] Spring Boot 揭秘与实战 数据存储篇 - ElasticSearch

Posted 2020-09-14 天空之城

[From] http://www.tuicool.com/articles/JBvQrmj

 

本文讲解Spring Boot基础下，如何使用 ElasticSearch，实现全文搜索。

版本须知

spring data elasticSearch 的版本与Spring boot、Elasticsearch版本需要匹配。

Spring Boot Version (x)	Spring Data Elasticsearch Version (y)	Elasticsearch Version (z)
x <= 1.3.5	y <= 1.3.4	z <= 1.7.2
x >= 1.4.x	2.0.0 <=y <5.0.0	2.0.0 <= z < 5.0.0

环境依赖

修改 POM 文件，添加 spring-boot-starter-data-elasticsearch 依赖。

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

数据源

方案一 使用 Spring Boot 默认配置

在 src/main/resources/application.properties 中配置数据源信息。

spring.data.elasticsearch.properties.host = 127.0.0.1
spring.data.elasticsearch.properties.port = 9300

通过 Java Config 创建ElasticSearchConfig。

@Configuration
@EnableElasticsearchRepositories("com.lianggzone.springboot.action.data.elasticsearch")
public class ElasticSearchConfig {}

方案二 手动创建

通过 Java Config 创建ElasticSearchConfig。

@Configuration
@EnableElasticsearchRepositories("com.lianggzone.springboot.action.data.elasticsearch")
public class ElasticsearchConfig2 {

    private String hostname = "127.0.0.1";
    private int port = 9300;

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

    @Bean
    public Client client() {
        TransportClient client = new TransportClient();
        TransportAddress address = new InetSocketTransportAddress(hostname, port);

        client.addTransportAddress(address);
        return client;
    }
}

业务操作

实体对象

@Document(indexName = "springbootdb", type = "news")
public class News {

    @Id
    private String id;

    private String title;

    private String content;

    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyyMMdd‘T‘HHmmss.SSS‘Z‘")
    @Field(type = FieldType.Date, format = DateFormat.basic_date_time, index = FieldIndex.not_analyzed)
    @CreatedDate
    private Date createdDateTime;

    // GET和SET方法
}

DAO相关

public interface NewsRepository extends ElasticsearchRepository<News, String> {
    public List<News> findByTitle(String title);
}

Service相关

我们来定义实现类，Service层调用Dao层的方法，这个是典型的套路。

@Service
public class NewsService {

    @Autowired
    private NewsRepository newsRepository;

    public Iterable<News> findAll(){
        return newsRepository.findAll();
    }

    public Iterable<News> search(QueryBuilder query){
        return newsRepository.search(query);
    }

    public List <News> findByTitle(String title) {
        return this.newsRepository.findByTitle(title);
    }

    public void deleteAll(String id){
        this.newsRepository.delete(id);
    }

    public void init(){
        for (int i = 0; i < 100; i++) {
            News news = new News();
            news.setId(i+"");
            news.setTitle(i + ".梁桂钊单元测试用例");
            news.setContent("梁桂钊单元测试用例"+i+"xxxxx");
            news.setCreatedDateTime(new Date());
            this.newsRepository.save(news);
        }
    }
}

Controller相关

为了展现效果，我们先定义一组简单的 RESTful API 接口进行测试。

@RestController
@RequestMapping(value="/data/elasticsearch/news")
public class NewsController {

    @Autowired
    private NewsService newsService;

    /**
     * 初始化
     * @param request
     */
    @RequestMapping(value = "/init", method = RequestMethod.POST)
    public void init(HttpServletRequest request) {
        this.newsService.init();
    }

    /**
     * findAll        
     * @param request
     * @return
     */
    @RequestMapping(value = "/", method = RequestMethod.GET)
    public Map<String, Object> findList(HttpServletRequest request) {
        Map<String, Object> params = new HashMap<String, Object>();
        params.put("items", this.newsService.findAll());
        return params;
    }

    /**
     * find      
     * @param request
     * @return
     */
    @RequestMapping(value = "/{title}", method = RequestMethod.GET)
    public Map<String, Object> search(@PathVariable String title) {
        // 构建查询条件
        QueryBuilder queryBuilder = QueryBuilders.queryString(title);
        Map<String, Object> params = new HashMap<String, Object>();
        params.put("items", this.newsService.search(queryBuilder));
        return params;
    }
}

总结

上面这个简单的案例，让我们看到了 Spring Boot 整合 ElasticSearch 流程如此简单。