ElasticSearch是一个基于Lucene的搜索服务器。它提供了一个分布式多用户能力的全文搜索引擎,基于RESTful web接口。
Elasticsearch是用Java开发的,并作为Apache许可条款下的开放源码发布,是当前流行的企业级搜索引擎。设计用于云计算中,能够达到实时搜索,稳定,可靠,快速,安装使用方便。
安装相关软件
软件名称 | 软件版本 | 下载地址 |
---|---|---|
Elasticsearch | 6.2.4 | elasticsearch官网下载 |
IK中文分词器 | 6.2.4 | ik分词器官网下载 |
kibana | 6.2.4 | kibana官网下载 |
安装教程百度一搜一大把,这里就不作详细解释,只说明如下几点
注意:elasticsearch自带jdk,注意Linux环境中的jdk和自带的jdk冲突!
安装完成之后启动es,默认启动端口为9200
./bin/elasticsearch
./bin/elasticsearch -d # 后台运行
浏览器访问: http://ip:9200/ 会得到相应的版本信息,如
{
"name": "Bb-td48",
"cluster_name": "elasticsearch",
"cluster_uuid": "_IM0iQAeToWALU0tq7rsZQ",
"version": {
"number": "6.2.4",
"build_hash": "ccec39f",
"build_date": "2018-04-12T20:37:28.497551Z",
"build_snapshot": false,
"lucene_version": "7.2.1",
"minimum_wire_compatibility_version": "5.6.0",
"minimum_index_compatibility_version": "5.0.0"
},
"tagline": "You Know, for Search"
}
为什么要在elasticsearch中要使用ik这样的中文分词呢,那是因为es提供的分词是英文分词,对于中文的分词就做的非常不好了,因此我们需要一个中文分词器来用于搜索和使用。今天我们就尝试安装下IK分词。
1、去github 下载对应的分词插件,根据不同版本下载不同的分词插件
https://github.com/medcl/elasticsearch-analysis-ik/releases
2、到es的plugins 目录创建文件夹
cd your-es-root/plugins/ && mkdir ik
3、解压ik分词插件到ik文件夹
unzip elasticsearch-analysis-ik-6.4.3.zip
Kibana可以到官网去下载,不过网速都是特别感人,这里提供一个华为云镜像地址,下载速度嗖嗖的!
https://mirrors.huaweicloud.com/kibana/
里面有所有版本的Kibana提供下载!
解压
tar -zxvf kibana-6.3.2-linux-x86_64.tar.gz
修改配置文件
vim config/kibana.yml
# 放开注释,将默认配置改成如下:
server.port: 5601
server.host: "0.0.0.0"
elasticsearch.url: "http://192.168.202.128:9200"
kibana.index: ".kibana"
启动
bin/kibana
启动失败 报错如下
这个很明显是没有权限,一次切换root用户 给es用户这个文件的权限
chown -R 用户名:用户名 /usr/local/elasticsearch/kibana/kibana-7.8.0/
但是下面的警告出事了,这里并不是找不到啥导致报错,而是服务器内存不足造成的,所以,我选择放弃!
相信不用kibana照样玩转elasticsearch!
org.springframework.boot
spring-boot-starter-data-elasticsearch
还有lombok,自己加一下
上面的是整合依赖,由于测试等原因,加上其他的依赖
org.springframework.boot
spring-boot-starter-data-elasticsearch
org.projectlombok
lombok
junit
junit
org.springframework.boot
spring-boot-starter-test
commons-beanutils
commons-beanutils
1.9.3
spring:
data:
elasticsearch:
cluster-name: my-application
cluster-nodes: 101.201.101.206:9300
@Data
@AllArgsConstructor
@NoArgsConstructor
@Document(indexName = "item", type = "docs", shards = 1, replicas = 0)
public class Item {
@Id
private Long id;
@Field(type = FieldType.Text, analyzer = "ik_max_word")
private String title; //标题
@Field(type = FieldType.Keyword)
private String category;// 分类
@Field(type = FieldType.Keyword)
private String brand; // 品牌
@Field(type = FieldType.Double)
private Double price; // 价格
@Field(index = false, type = FieldType.Keyword)
private String images; // 图片地址
}
Spring Data通过注解来声明字段的映射属性,有下面的三个注解:
@Document
作用在类,标记实体类为文档对象,一般有两个属性
@Id
作用在成员变量,标记一个字段作为id主键
@Field
作用在成员变量,标记为文档的字段,并指定字段映射属性:
需要提供一个repository仓库
public interface ItemRepository extends ElasticsearchRepository<Item, Long> {
/**
* 根据价格区间查询
*
* @param price1
* @param price2
* @return
*/
List<Item> findByPriceBetween(double price1, double price2);
}
这里对elasticsearch做增删改查!
@RunWith(SpringRunner.class)
@SpringBootTest
public class SpringbootElasticsearchApplicationTests {
@Autowired
private ElasticsearchTemplate elasticsearchTemplate;
@Autowired
private ItemRepository itemRepository;
/**
* 创建索引
*/
@Test
public void createIndex() {
// 创建索引,会根据Item类的@Document注解信息来创建
elasticsearchTemplate.createIndex(Item.class);
// 配置映射,会根据Item类中的id、Field等字段来自动完成映射
elasticsearchTemplate.putMapping(Item.class);
}
/**
* 删除索引
*/
@Test
public void deleteIndex() {
elasticsearchTemplate.deleteIndex("item");
}
/**
* 新增
*/
@Test
public void insert() {
Item item = new Item(1L, "小米手机7", "手机", "小米", 2999.00, "https://img12.360buyimg.com/n1/s450x450_jfs/t1/14081/40/4987/124705/5c371b20E53786645/c1f49cd69e6c7e6a.jpg");
itemRepository.save(item);
}
/**
* 批量新增
*/
@Test
public void insertList() {
List<Item> list = new ArrayList<>();
list.add(new Item(2L, "坚果手机R1", "手机", "锤子", 3999.00, "https://img12.360buyimg.com/n1/s450x450_jfs/t1/14081/40/4987/124705/5c371b20E53786645/c1f49cd69e6c7e6a.jpg"));
list.add(new Item(3L, "华为META20", "手机", "华为", 4999.00, "https://img12.360buyimg.com/n1/s450x450_jfs/t1/14081/40/4987/124705/5c371b20E53786645/c1f49cd69e6c7e6a.jpg"));
list.add(new Item(4L, "iPhone X", "手机", "iPhone", 5100.00, "https://img12.360buyimg.com/n1/s450x450_jfs/t1/14081/40/4987/124705/5c371b20E53786645/c1f49cd69e6c7e6a.jpg"));
list.add(new Item(5L, "iPhone XS", "手机", "iPhone", 5999.00, "https://img12.360buyimg.com/n1/s450x450_jfs/t1/14081/40/4987/124705/5c371b20E53786645/c1f49cd69e6c7e6a.jpg"));
// 接收对象集合,实现批量新增
itemRepository.saveAll(list);
}
/**
* 修改
*
* :修改和新增是同一个接口,区分的依据就是id,这一点跟我们在页面发起PUT请求是类似的。
*/
/**
* 删除所有
*/
@Test
public void delete() {
itemRepository.deleteAll();
}
/**
* 基本查询
*/
@Test
public void query() {
// 查询全部,并按照价格降序排序
Iterable<Item> items = itemRepository.findAll(Sort.by("price").descending());
items.forEach(item -> System.out.println("item = " + item));
}
/**
* 自定义方法
*/
@Test
public void queryByPriceBetween() {
// 根据价格区间查询
List<Item> list = itemRepository.findByPriceBetween(5000.00, 6000.00);
list.forEach(item -> System.out.println("item = " + item));
}
/**
* 自定义查询
*/
@Test
public void search() {
// 构建查询条件
NativeSearchQueryBuilder queryBuilder = new NativeSearchQueryBuilder();
// 添加基本分词查询
queryBuilder.withQuery(QueryBuilders.matchQuery("title", "小米手机"));
// 搜索,获取结果
Page<Item> items = itemRepository.search(queryBuilder.build());
// 总条数
long total = items.getTotalElements();
System.out.println("total = " + total);
items.forEach(item -> System.out.println("item = " + item));
}
/**
* 分页查询
*/
@Test
public void searchByPage() {
// 构建查询条件
NativeSearchQueryBuilder queryBuilder = new NativeSearchQueryBuilder();
// 添加基本分词查询
queryBuilder.withQuery(QueryBuilders.termQuery("category", "手机"));
// 分页:
int page = 0;
int size = 2;
queryBuilder.withPageable(PageRequest.of(page, size));
// 搜索,获取结果
Page<Item> items = itemRepository.search(queryBuilder.build());
long total = items.getTotalElements();
System.out.println("总条数 = " + total);
System.out.println("总页数 = " + items.getTotalPages());
System.out.println("当前页:" + items.getNumber());
System.out.println("每页大小:" + items.getSize());
items.forEach(item -> System.out.println("item = " + item));
}
/**
* 排序
*/
@Test
public void searchAndSort() {
// 构建查询条件
NativeSearchQueryBuilder queryBuilder = new NativeSearchQueryBuilder();
// 添加基本分词查询
queryBuilder.withQuery(QueryBuilders.termQuery("category", "手机"));
// 排序
queryBuilder.withSort(SortBuilders.fieldSort("price").order(SortOrder.ASC));
// 搜索,获取结果
Page<Item> items = this.itemRepository.search(queryBuilder.build());
// 总条数
long total = items.getTotalElements();
System.out.println("总条数 = " + total);
items.forEach(item -> System.out.println("item = " + item));
}
/**
* 聚合为桶
*/
@Test
public void testAgg() {
NativeSearchQueryBuilder queryBuilder = new NativeSearchQueryBuilder();
// 不查询任何结果
queryBuilder.withSourceFilter(new FetchSourceFilter(new String[]{
""}, null));
// 1、添加一个新的聚合,聚合类型为terms,聚合名称为brands,聚合字段为brand
queryBuilder.addAggregation(AggregationBuilders.terms("brands").field("brand"));
// 2、查询,需要把结果强转为AggregatedPage类型
AggregatedPage<Item> aggPage = (AggregatedPage<Item>) itemRepository.search(queryBuilder.build());
// 3、解析
// 3.1、从结果中取出名为brands的那个聚合,
// 因为是利用String类型字段来进行的term聚合,所以结果要强转为StringTerm类型
StringTerms agg = (StringTerms) aggPage.getAggregation("brands");
// 3.2、获取桶
List<StringTerms.Bucket> buckets = agg.getBuckets();
// 3.3、遍历
for (StringTerms.Bucket bucket : buckets) {
// 3.4、获取桶中的key,即品牌名称
System.out.println(bucket.getKeyAsString());
// 3.5、获取桶中的文档数量
System.out.println(bucket.getDocCount());
}
}
/**
* 嵌套聚合,求平均值
*/
@Test
public void testSubAgg() {
NativeSearchQueryBuilder queryBuilder = new NativeSearchQueryBuilder();
// 不查询任何结果
queryBuilder.withSourceFilter(new FetchSourceFilter(new String[]{
""}, null));
// 1、添加一个新的聚合,聚合类型为terms,聚合名称为brands,聚合字段为brand
queryBuilder.addAggregation(
AggregationBuilders.terms("brands").field("brand")
.subAggregation(AggregationBuilders.avg("priceAvg").field("price")) // 在品牌聚合桶内进行嵌套聚合,求平均值
);
// 2、查询,需要把结果强转为AggregatedPage类型
AggregatedPage<Item> aggPage = (AggregatedPage<Item>) this.itemRepository.search(queryBuilder.build());
// 3、解析
// 3.1、从结果中取出名为brands的那个聚合,
// 因为是利用String类型字段来进行的term聚合,所以结果要强转为StringTerm类型
StringTerms agg = (StringTerms) aggPage.getAggregation("brands");
// 3.2、获取桶
List<StringTerms.Bucket> buckets = agg.getBuckets();
// 3.3、遍历
for (StringTerms.Bucket bucket : buckets) {
// 3.4、获取桶中的key,即品牌名称 3.5、获取桶中的文档数量
System.out.println(bucket.getKeyAsString() + ",共" + bucket.getDocCount() + "台");
// 3.6.获取子聚合结果:
InternalAvg avg = (InternalAvg) bucket.getAggregations().asMap().get("priceAvg");
System.out.println("平均售价:" + avg.getValue());
}
}
}
下面是测试类中的一个查询方法,并进行高亮显示
@org.junit.Test
public void search() {
// 构建查询条件
NativeSearchQueryBuilder queryBuilder = new NativeSearchQueryBuilder();
// 添加基本分词查询
queryBuilder.withQuery(QueryBuilders.matchQuery("title", "搜索引擎"));
HighlightBuilder.Field hfield= new HighlightBuilder.Field("title")
.preTags("")
.postTags("")
.fragmentSize(100);
queryBuilder.withHighlightFields(hfield);
// 搜索,获取结果
Page<Item> items = itemRepository.search(queryBuilder.build());
// 总条数
long total = items.getTotalElements();
System.out.println("total = " + total);
items.forEach(item -> System.out.println("item = " + item));
}
但是没有效果,百度发现,这个版本的mapper实现类没有设置高亮显示的字段,改正后的结果
新建一个MyResultMapper ,继承AbstractResultMapper 并对其方法进行重写,结果如下
其中需要上面的BeanUtils的依赖!
package com.example.elasticsearch.springbootelasticsearch.repository;
import com.fasterxml.jackson.core.JsonEncoding;
import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import org.apache.commons.beanutils.PropertyUtils;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.get.MultiGetItemResponse;
import org.elasticsearch.action.get.MultiGetResponse;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.common.document.DocumentField;
import org.elasticsearch.common.text.Text;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.springframework.data.domain.Pageable;
import org.springframework.data.elasticsearch.ElasticsearchException;
import org.springframework.data.elasticsearch.annotations.Document;
import org.springframework.data.elasticsearch.annotations.ScriptedField;
import org.springframework.data.elasticsearch.core.AbstractResultMapper;
import org.springframework.data.elasticsearch.core.DefaultEntityMapper;
import org.springframework.data.elasticsearch.core.EntityMapper;
import org.springframework.data.elasticsearch.core.aggregation.AggregatedPage;
import org.springframework.data.elasticsearch.core.aggregation.impl.AggregatedPageImpl;
import org.springframework.data.elasticsearch.core.mapping.ElasticsearchPersistentEntity;
import org.springframework.data.elasticsearch.core.mapping.ElasticsearchPersistentProperty;
import org.springframework.data.elasticsearch.core.mapping.SimpleElasticsearchMappingContext;
import org.springframework.data.mapping.context.MappingContext;
import org.springframework.stereotype.Component;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.nio.charset.Charset;
import java.util.*;
@Component
public class MyResultMapper extends AbstractResultMapper {
private final MappingContext<? extends ElasticsearchPersistentEntity<?>, ElasticsearchPersistentProperty> mappingContext;
public MyResultMapper() {
this(new SimpleElasticsearchMappingContext());
}
public MyResultMapper(MappingContext<? extends ElasticsearchPersistentEntity<?>, ElasticsearchPersistentProperty> mappingContext) {
super(new DefaultEntityMapper(mappingContext));
Assert.notNull(mappingContext, "MappingContext must not be null!");
this.mappingContext = mappingContext;
}
public MyResultMapper(EntityMapper entityMapper) {
this(new SimpleElasticsearchMappingContext(), entityMapper);
}
public MyResultMapper(
MappingContext<? extends ElasticsearchPersistentEntity<?>, ElasticsearchPersistentProperty> mappingContext,
EntityMapper entityMapper) {
super(entityMapper);
Assert.notNull(mappingContext, "MappingContext must not be null!");
this.mappingContext = mappingContext;
}
@Override
public <T> AggregatedPage<T> mapResults(SearchResponse response, Class<T> clazz, Pageable pageable) {
long totalHits = response.getHits().getTotalHits();
float maxScore = response.getHits().getMaxScore();
List<T> results = new ArrayList<>();
for (SearchHit hit : response.getHits()) {
if (hit != null) {
T result = null;
if (!StringUtils.isEmpty(hit.getSourceAsString())) {
result = mapEntity(hit.getSourceAsString(), clazz);
} else {
result = mapEntity(hit.getFields().values(), clazz);
}
setPersistentEntityId(result, hit.getId(), clazz);
setPersistentEntityVersion(result, hit.getVersion(), clazz);
setPersistentEntityScore(result, hit.getScore(), clazz);
populateScriptFields(result, hit);
results.add(result);
}
}
return new AggregatedPageImpl<T>(results, pageable, totalHits, response.getAggregations(), response.getScrollId(),
maxScore);
}
private String concat(Text[] texts) {
StringBuilder sb = new StringBuilder();
for (Text text : texts) {
sb.append(text.toString());
}
return sb.toString();
}
private <T> void populateScriptFields(T result, SearchHit hit) {
if (hit.getFields() != null && !hit.getFields().isEmpty() && result != null) {
for (java.lang.reflect.Field field : result.getClass().getDeclaredFields()) {
ScriptedField scriptedField = field.getAnnotation(ScriptedField.class);
if (scriptedField != null) {
String name = scriptedField.name().isEmpty() ? field.getName() : scriptedField.name();
DocumentField searchHitField = hit.getFields().get(name);
if (searchHitField != null) {
field.setAccessible(true);
try {
field.set(result, searchHitField.getValue());
} catch (IllegalArgumentException e) {
throw new ElasticsearchException(
"failed to set scripted field: " + name + " with value: " + searchHitField.getValue(), e);
} catch (IllegalAccessException e) {
throw new ElasticsearchException("failed to access scripted field: " + name, e);
}
}
}
}
}
for (HighlightField field : hit.getHighlightFields().values()) {
try {
PropertyUtils.setProperty(result, field.getName(), concat(field.fragments()));
} catch (InvocationTargetException | IllegalAccessException | NoSuchMethodException e) {
throw new ElasticsearchException("failed to set highlighted value for field: " + field.getName()
+ " with value: " + Arrays.toString(field.getFragments()), e);
}
}
}
private <T> T mapEntity(Collection<DocumentField> values, Class<T> clazz) {
return mapEntity(buildJSONFromFields(values), clazz);
}
private String buildJSONFromFields(Collection<DocumentField> values) {
JsonFactory nodeFactory = new JsonFactory();
try {
ByteArrayOutputStream stream = new ByteArrayOutputStream();
JsonGenerator generator = nodeFactory.createGenerator(stream, JsonEncoding.UTF8);
generator.writeStartObject();
for (DocumentField value : values) {
if (value.getValues().size() > 1) {
generator.writeArrayFieldStart(value.getName());
for (Object val : value.getValues()) {
generator.writeObject(val);
}
generator.writeEndArray();
} else {
generator.writeObjectField(value.getName(), value.getValue());
}
}
generator.writeEndObject();
generator.flush();
return new String(stream.toByteArray(), Charset.forName("UTF-8"));
} catch (IOException e) {
return null;
}
}
@Override
public <T> T mapResult(GetResponse response, Class<T> clazz) {
T result = mapEntity(response.getSourceAsString(), clazz);
if (result != null) {
setPersistentEntityId(result, response.getId(), clazz);
setPersistentEntityVersion(result, response.getVersion(), clazz);
}
return result;
}
@Override
public <T> LinkedList<T> mapResults(MultiGetResponse responses, Class<T> clazz) {
LinkedList<T> list = new LinkedList<>();
for (MultiGetItemResponse response : responses.getResponses()) {
if (!response.isFailed() && response.getResponse().isExists()) {
T result = mapEntity(response.getResponse().getSourceAsString(), clazz);
setPersistentEntityId(result, response.getResponse().getId(), clazz);
setPersistentEntityVersion(result, response.getResponse().getVersion(), clazz);
list.add(result);
}
}
return list;
}
private <T> void setPersistentEntityId(T result, String id, Class<T> clazz) {
if (clazz.isAnnotationPresent(Document.class)) {
ElasticsearchPersistentEntity<?> persistentEntity = mappingContext.getRequiredPersistentEntity(clazz);
ElasticsearchPersistentProperty idProperty = persistentEntity.getIdProperty();
// Only deal with String because ES generated Ids are strings !
if (idProperty != null && idProperty.getType().isAssignableFrom(String.class)) {
persistentEntity.getPropertyAccessor(result).setProperty(idProperty, id);
}
}
}
private <T> void setPersistentEntityVersion(T result, long version, Class<T> clazz) {
if (clazz.isAnnotationPresent(Document.class)) {
ElasticsearchPersistentEntity<?> persistentEntity = mappingContext.getPersistentEntity(clazz);
ElasticsearchPersistentProperty versionProperty = persistentEntity.getVersionProperty();
// Only deal with Long because ES versions are longs !
if (versionProperty != null && versionProperty.getType().isAssignableFrom(Long.class)) {
// check that a version was actually returned in the response, -1 would indicate that
// a search didn't request the version ids in the response, which would be an issue
Assert.isTrue(version != -1, "Version in response is -1");
persistentEntity.getPropertyAccessor(result).setProperty(versionProperty, version);
}
}
}
private <T> void setPersistentEntityScore(T result, float score, Class<T> clazz) {
if (clazz.isAnnotationPresent(Document.class)) {
ElasticsearchPersistentEntity<?> entity = mappingContext.getRequiredPersistentEntity(clazz);
if (!entity.hasScoreProperty()) {
return;
}
entity.getPropertyAccessor(result) //
.setProperty(entity.getScoreProperty(), score);
}
}
}
虎你呢,没了!再见!
上面的已经够用了,兄弟萌!