第十一章-SpringBoot 与检索

ElasticSearch 分布式搜索服务,底层基于 Lucene

安装 elasticsearch

docker search elasticsearch

docker pull elasticsearch

docker images

docker run -e ES_JAVA_OPTS="-Xms256m -Xmx256m" -d -p 9200:9200 -p 9300:9300 --name ES01 elasticsearch

http://localhost:9200/

Elasticsearch 快速入门

文档：https://www.elastic.co/guide/cn/elasticsearch/guide/current/index.html

ES: 集群-索引-类型-文档-属性
MySQL: ?-数据库-表-记录-列

使用 PostMan 发送请求

请求方式

POST /{index}/{type}/{id}

基本操作

# 存入文档
PUT /data/employee/1
{
  "name": "Tom",
  "age": 23
}

# 获取文档
GET /data/employee/1

# 检查存在
HEAD /data/employee/4

# 返回状态码
# 存在：200
# 不存在：404

# 删除
DELETE http://localhost:9200/data/employee/3

# 更新文档
PUT /data/employee/1
{
  "name": "Tom",
  "age": 24
}

# 搜索数据
GET /data/employee/_search

# 使用查询字符串
GET /data/employee/_search?q=name:Tom

# 使用查询体
POST /data/employee/_search
{
  "query": {
    "match": {
      "name": "Tom"
    }
  }
}

# 复杂查询
POST /data/employee/_search
{
  "query": {
    "bool": {
      "must": {
        "match": {
          "name": "Tom"
        }
      },
      "filter": {
        "range": {
          "age": {
            "gt": 20
          }
        }
      }
    }
  }
}

# 短语搜索(必须完全匹配)

POST /data/employee/_search
{
  "query": {
    "match_phrase": {
      "name": "Tom Steve"
    }
  }
}


# 高亮结果 会增加em标签
POST /data/employee/_search
{
  "query": {
    "match_phrase": {
      "name": "Tom Steve"
    }
  },
  "highlight": {
    "fields": {
      "name": {}
    }
  }
}

SpringBoot 整合 Jest 操作 ES

依赖

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

SpringBoot 支持两种技术和 ES 交互

• Jest 默认不生效 io.searchbox.client.JestClient
• SpringData ElasticSearch 操作 ES
• Client
• ElasticsearchTemplate
• ElasticSearchRepository

1、使用 Jest

Github: https://github.com/searchbox-io/Jest

<dependency>
    <groupId>io.searchbox</groupId>
    <artifactId>jest</artifactId>
    <version>5.3.4</version>
</dependency>

版本适配

Spring Data Release Train	Spring Data Elasticsearch	Elasticsearch	Spring Boot
Neumann	4.0.x	7.6.2	2.3.x
Moore	3.2.x	6.8.6	2.2.x
Lovelace	3.1.x	6.2.2	2.1.x
Kay	3.0.x	5.5.0	2.0.x
Ingalls	2.1.x	2.4.0	1.5.x

来源：
https://docs.spring.io/spring-data/elasticsearch/docs/4.0.2.RELEASE/reference/html/#preface.versions

# 拉取
docker pull elasticsearch:7.6.2

# 单节点启动
docker run -d \
-e ES_JAVA_POTS="-Xms256m -Xmx256m" \
-e "discovery.type=single-node" \
-p 9200:9200 \
-p 9300:9300 \
--name ES1 \
elasticsearch:7.6.2

# 查看所有容器
docker ps -a

# 删除
docker rm <容器ID>

# 查看日志
docker logs -f <容器ID>

查看数据
http://localhost:9200/data/_search

SpringBoot 操作 elasticsearch

文档：
https://github.com/spring-projects/spring-data-elasticsearch

package com.example.demo.pojo;

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

@Document(indexName="data")
public class Book {
    private Integer id;
    private String name;
    private String author;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    @Override
    public String toString() {
        return "Book{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", author='" + author + '\'' +
                '}';
    }
}

package com.example.demo.repository;

import com.example.demo.pojo.Book;
import org.springframework.data.elasticsearch.repository.ElasticsearchRepository;

import java.util.List;

public interface BookRepository extends ElasticsearchRepository<Book, Integer> {
    List<Book> findByNameLike(String name);
}

package com.example.demo;


import com.example.demo.pojo.Book;
import com.example.demo.repository.BookRepository;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.util.List;
import java.util.Optional;

@SpringBootTest
public class ElasticSearchTest {
    @Autowired
    public BookRepository bookRepository;


    @Test
    public void testSave(){
        Book book = new Book();
        book.setId(1);
        book.setName("<tom>");
        book.setAuthor("Jack");

        bookRepository.save(book);
    }

    @Test
    public void testQuery01(){
        Optional result= bookRepository.findById(1);
        if(result.isPresent()){
            System.out.println(result.get());
        }
    }

    @Test
    public void testQuery02(){
        List<Book> list =  bookRepository.findByNameLike("To");
        System.out.println(list);
    }

}

接口方法命名

https://docs.spring.io/spring-data/elasticsearch/docs/4.0.2.RELEASE/reference/html/#elasticsearch.query-methods.criterions