kotlin + springboot启用elasticsearch搜索

参考自：

http://how2j.cn/k/search-engine/search-engine-springboot/1791.html?p=78908

工具版本： elasticsearch 6.2.2、 kibana 6.2.2，  下载地址： elasticsearch、kibana

下载demo

1、kotlin版springboot项目创建

访问https://start.spring.io/， 创建项目demo（maven + kotlin + springboot 2.1.7， 其他默认）。

添加web支持、elasticsearch搜索及kotlin测试所需依赖

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-data-elasticsearch -->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-elasticsearch</artifactId>

        </dependency>

        <!-- https://mvnrepository.com/artifact/org.jetbrains.kotlin/kotlin-test-junit5 -->

        <dependency>

            <groupId>org.jetbrains.kotlin</groupId>

            <artifactId>kotlin-test-junit5</artifactId>

            <version>1.2.70</version>

            <scope>test</scope>

        </dependency>

最终pom.xml文件为

<?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>

    <parent>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-parent</artifactId>

        <version>2.1.7.RELEASE</version>

        <relativePath/> <!-- lookup parent from repository -->

    </parent>

    <groupId>com.example</groupId>

    <artifactId>demo</artifactId>

    <version>0.0.1-SNAPSHOT</version>

    <name>demo</name>

    <description>Demo project for Spring Boot</description>

    <properties>

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

        <kotlin.version>1.2.71</kotlin.version>

    </properties>

    <dependencies>

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter</artifactId>

        </dependency>

        <dependency>

            <groupId>org.jetbrains.kotlin</groupId>

            <artifactId>kotlin-reflect</artifactId>

        </dependency>

        <dependency>

            <groupId>org.jetbrains.kotlin</groupId>

            <artifactId>kotlin-stdlib-jdk8</artifactId>

        </dependency>

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-test</artifactId>

            <scope>test</scope>

        </dependency>

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-data-elasticsearch -->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-elasticsearch</artifactId>

        </dependency>

        <!-- https://mvnrepository.com/artifact/org.jetbrains.kotlin/kotlin-test-junit5 -->

        <dependency>

            <groupId>org.jetbrains.kotlin</groupId>

            <artifactId>kotlin-test-junit5</artifactId>

            <version>1.2.70</version>

            <scope>test</scope>

        </dependency>

    </dependencies>

    <build>

        <sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>

        <testSourceDirectory>${project.basedir}/src/test/kotlin</testSourceDirectory>

        <plugins>

            <plugin>

                <groupId>org.springframework.boot</groupId>

                <artifactId>spring-boot-maven-plugin</artifactId>

            </plugin>

            <plugin>

                <groupId>org.jetbrains.kotlin</groupId>

                <artifactId>kotlin-maven-plugin</artifactId>

                <configuration>

                    <args>

                        <arg>-Xjsr305=strict</arg>

                    </args>

                    <compilerPlugins>

                        <plugin>spring</plugin>

                    </compilerPlugins>

                </configuration>

                <dependencies>

                    <dependency>

                        <groupId>org.jetbrains.kotlin</groupId>

                        <artifactId>kotlin-maven-allopen</artifactId>

                        <version>${kotlin.version}</version>

                    </dependency>

                </dependencies>

            </plugin>

        </plugins>

    </build>

</project>

2、创建实体类Category.kt

package com.example.demo.entity

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

@Document(indexName = "test", type = "category")

class Category {

    var id : Int? = null;

    var name : String? = null;

}

es操作dao类CategoryESDAO.kt

package com.example.demo.es

import com.example.demo.entity.Category

import org.springframework.data.elasticsearch.repository.ElasticsearchRepository

interface CategoryESDAO : ElasticsearchRepository<Category, Int>

创建类SearchController.kt，并实现搜索方法，这里根据keyword作为前缀进行搜索

package com.example.demo.controller

import com.example.demo.entity.Category

import com.example.demo.es.CategoryESDAO

import org.elasticsearch.common.lucene.search.function.FunctionScoreQuery

import org.elasticsearch.index.query.QueryBuilders

import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders

import org.springframework.data.domain.PageRequest

import org.springframework.data.domain.Sort

import org.springframework.data.elasticsearch.core.query.NativeSearchQueryBuilder

import org.springframework.stereotype.Controller

import org.springframework.web.bind.annotation.GetMapping

import org.springframework.web.bind.annotation.RequestParam

import org.springframework.web.bind.annotation.RestController

import javax.annotation.Resource

@RestController

class SearchController {

    @Resource

    private lateinit var categoryESDAO: CategoryESDAO

    @GetMapping("/search")

    fun search(@RequestParam(value = "keyword") keyword: String, @RequestParam(value = "start", defaultValue = "0") start: Int,

               @RequestParam(value = "size", defaultValue = "5") size: Int): List<Category> {

        val queryBuilder = QueryBuilders.matchPhrasePrefixQuery("name", keyword)

        val sort = Sort(Sort.Direction.DESC, "id")

        val pageable = PageRequest.of(start, size, sort)

        val searchQuery = NativeSearchQueryBuilder()

                .withPageable(pageable)

                .withQuery(queryBuilder).build()

        val page = categoryESDAO.search(searchQuery)

        return page.content.filter {category ->  category != null}.toList()

    }

}

在类DemoApplication.kt中指定包名，

package com.example.demo

import org.springframework.boot.autoconfigure.SpringBootApplication

import org.springframework.boot.runApplication

import org.springframework.data.elasticsearch.repository.config.EnableElasticsearchRepositories

@SpringBootApplication

@EnableElasticsearchRepositories(basePackages = ["com.example.demo.es"])

class DemoApplication

fun main(args: Array<String>) {

    runApplication<DemoApplication>(*args)

}

在resources目录下application.properties中增加elasticsearch的参数

#ElasticSearch

spring.data.elasticsearch.cluster-nodes = 127.0.0.1:9300

3、创建测试类

在test/kotlin目录下com.example.demo包下创建类TestSearchController.kt测试搜索

package com.example.demo

import com.example.demo.entity.Category

import com.example.demo.es.CategoryESDAO

import org.junit.jupiter.api.BeforeAll

import org.junit.jupiter.api.BeforeEach

import org.junit.jupiter.api.Test

import org.junit.jupiter.api.TestInstance

import org.springframework.boot.test.context.SpringBootTest

import org.springframework.http.HttpMethod

import org.springframework.test.context.web.WebAppConfiguration

import org.springframework.test.web.servlet.request.MockMvcRequestBuilders

import org.springframework.test.web.servlet.result.MockMvcResultMatchers

import org.springframework.test.web.servlet.setup.MockMvcBuilders

import org.springframework.web.context.WebApplicationContext

import javax.annotation.Resource

@SpringBootTest

@WebAppConfiguration

class TestSearchController {

    @Resource

    private lateinit var wac : WebApplicationContext

    @Resource

    private lateinit var categoryESDAO: CategoryESDAO

    @BeforeEach

    fun add() {

        for (ch in 'a'..'z') {

            val category = Category()

            category.id = ch - 'a'

            category.name = ch.toUpperCase().toString().plus(ch)

            categoryESDAO.save(category)

        }

    }

    @Test

    fun test() {

        val mockMvc = MockMvcBuilders.webAppContextSetup(wac).build()

        val result = mockMvc.perform(MockMvcRequestBuilders.request(HttpMethod.GET, "/search?keyword=Aa"))

                .andExpect(MockMvcResultMatchers.status().isOk)

                .andDo(::println)

                .andReturn().response.contentAsString;

        println(result)

    }

}

依次启动elasticsearch6.2.2、kibana6.2.2，

在浏览器中打开http://localhost:5601/app/kibana#/dev_tools/console?_g=()

执行

PUT test

创建test（对应Category类Document注解 indexName）索引，然后执行TestSearchController类进行测试，

控制台输出结果为：

[{"id":0,"name":"Aa"}]