SpringBoot集成ElasticSearch

序言

本章需要你在掌握基本的SpringBoot、JPA和一些ElasticSearch(以下简称：“Es”)的知识下进行服用。

环境

SpringBoot :2.2.6.RELEASE
Es:6.8.7（集群-3节点，且安装了ik分词器）
kibana 6.8.7

说明

测试环境的Es是6.8.7的3节点，代码相关依赖也是和Es服务端保持一致。当然大版本的6和7 Es的Api还是有些区别，具体Api的使用可以去官网进行翻阅，这里是以6.8版本进行讲解。

开始搭建

基本依赖

	 	<parent>
	        <groupId>org.springframework.boot</groupId>
	        <artifactId>spring-boot-starter-parent</artifactId>
	        <version>2.2.6.RELEASE</version>
	        <relativePath/> <!-- lookup parent from repository -->
	    </parent>

		<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
        </dependency>
         <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.22</version>
        </dependency>

yml配置

server:
  port: 8801
spring:
  application:
    name: esSpringboot
  elasticsearch:
    rest:
      uris: 192.168.1.195:9200,192.168.1.195:9201,192.168.1.195:9202 #设置集群

如何使用

实体

@Document(indexName = "student",type = "_doc",replicas = 0,shards = 3)
@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
public class Student implements Serializable {

    private static final long serialVersionUID = -1479160581341748052L;

    /*ik_smart 粗精度，ik_max_word 细精度*/
    @Field(type = FieldType.Text,searchAnalyzer = "ik_smart",analyzer = "ik_max_word")
    private String name;

    /*text类型开启统计的时候需要设置属性fielddata = true 正排索引*/
    @Field(type = FieldType.Long)
    private Integer age;

    @Field(type = FieldType.Text)
    private String testNumber;

    @Id
    @Field(type = FieldType.Keyword)
    private String id;

    @Field(type =  FieldType.Keyword)
    private String email;

    @Field(type =  FieldType.Date,format = DateFormat.custom,pattern = "yyyy-MM-dd HH:mm:ss")
    @JsonFormat(shape =JsonFormat.Shape.STRING,pattern ="yyyy-MM-dd HH:mm:ss",timezone = "GMT+8")
    private Date birthDay;

}

这里需要你已经掌握Es的常用数据类型。

使用Repository

@Repository
public interface StudentRepository extends ElasticsearchRepository<Student,String> {

}

测试

批量添加

 public String saveBatch(){
        Faker faker = new Faker(Locale.CHINA);
        List<Student> collect = Stream.generate(() -> Student.builder()
                .age(faker.random().nextInt(1, 100))
                .email(faker.internet().emailAddress())
                .name(faker.name().username())
                .testNumber(faker.random().nextInt(1, 100)+"")
                .birthDay(new Date())
                .build()
        ).limit(1000).collect(Collectors.toList());
        studentRepository.saveAll(collect);
        return "ok";
    }

添加完成后我们在对应的kibana上面可以看到对应的Student索引和数据

执行指令查看添加数据的结果

POST /student/_search
{
  "query":{
    "match_all": {}
  }
}

结果

根据id查询

public Student getById( Long id){
        Optional<Student> byId = studentRepository.findById(id + "");
        return byId.get();
    }

根据id删除

public String removeById( Long id){
        studentRepository.deleteById(id + "");
        return "ok";
    }

当然也可以在Repository写一些Es的DSL查询语句

使用DSL

使用@Query 注解

    @Query("{\n" +
            "    \"term\": {\n" +
            "      \"name.keyword\": \"?0\"\n" +
            "    }\n" +
            "  }")
    List<Student> findStudentByName(String name);

复杂查询

• 分页
• 布尔
• term
• multiMatch
• matchPhrase
• fuzzy
• regep
• range

        Pageable pageable = PageRequest.of(0, 5);//分页
        BoolQueryBuilder boolQuery= boolQuery()
                /*term查询*/
//                .must(QueryBuilders.termQuery("name", student.getName()))
                /*range查询*/
                .must(QueryBuilders.rangeQuery("age").gte(0).lte(100))
                /*multiMatch*/
//                .must(QueryBuilders.multiMatchQuery(student.getEmail(), "name","email" ).operator(Operator.OR))
                /*matchPhraseQuery :紧邻查询，slop:允许间隔的单词个数*/
//                .must(QueryBuilders.matchPhraseQuery("name",student.getName()).slop(1))
                /*模糊匹配:查询的词也会分词 https://blog.csdn.net/weixin_42692506/article/details/101555035*/
//                .must(QueryBuilders.fuzzyQuery("name", "21").fuzziness(Fuzziness.AUTO))
                /*正则查询 [1-9] https://blog.csdn.net/u010483897/article/details/90485332*/
//                .must(QueryBuilders.regexpQuery("name", student.getName()))
                ;
                 SearchQuery searchQuery = new NativeSearchQueryBuilder()
                .withPageable(pageable)
                .withQuery(boolQuery)
                .build();
                Page<Student> search = studentRepository.search(searchQuery);
                List<Student> result= search.getContent();

聚合

• 平均值
• 求和
• 最大值
• 最小值
• 范围
• 时间范围
• 时间间隔
• 数值范围

    SearchQuery searchQuery = new NativeSearchQueryBuilder()
                /*name:统计的名称，field:统计的字段*/
                .addAggregation(AggregationBuilders.avg("ageAvg").field("age"))//平均值
                .addAggregation(AggregationBuilders.sum("ageSum").field("age"))//求和
                .addAggregation(AggregationBuilders.count("ageCount").field("age"))//有age的数目
                .addAggregation(AggregationBuilders.max("ageMax").field("age"))//最大值
                .addAggregation(AggregationBuilders.min("ageMin").field("age"))//最小值
                .addAggregation(AggregationBuilders.percentiles("agePercentiles").field("age"))//年龄百分比
                .addAggregation(AggregationBuilders.cardinality("ageCardinality").field("age"))//去重统计有多少数量
                .addAggregation(AggregationBuilders.terms("ageTerms").field("age").size(Integer.MAX_VALUE))//统计有相同age
                .addAggregation(AggregationBuilders.range("ageRange").field("age").addRange(0, 20)
                        .addRange(20, 40)
                        .addRange(40, 60)
                        .addRange(60, 80)
                )//查询年龄20~40，40~60，60~80范围统计
                .addAggregation(AggregationBuilders.dateRange("birthDayDateRange").field("birthDay").addRange("now/y-1y", "now/y")  //  now/y：当前年的1月1日  now：当前时间
                        .addRange("now/y-2y", "now/y-1y")  //  now/y-1y：当前年上一年的1月1日
                        .addRange("now/y-3y", "now/y-2y")
                        .format("yyyy-MM-dd"))//根据年统计
                /*年龄间隔统计 开始如果为20则后续设置统计就是20 22 24 26 28 30*/
                .addAggregation(AggregationBuilders.histogram("age_histogram_count")
                        .field("age")
                        .interval(20))
                /*时间统计 一定是对时间字段的统计，format是设置返回的key按照什么时间格式返回
                * 同时统计对应时间的年龄值合计
                * */
                .addAggregation(AggregationBuilders.dateHistogram("ageDateHistogram")
                        .field("birthDay")
                        .dateHistogramInterval(DateHistogramInterval.YEAR)
                        .format("yyyy-MM-dd HH:mm:ss")
                        .subAggregation(AggregationBuilders.sum("ageDateHistogramSum").field("age"))
                )
                   
AggregatedPage<Student> search = (AggregatedPage<Student>) studentRepository.search(searchQuery);
Aggregations aggregations = search.getAggregations();
Map<String, Aggregation> result= aggregations.getAsMap(); #获取聚合数据

参考

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