数据聚合、自动补全、数据同步、es集群
发布时间：2024年01月08日
目录
什么是聚合？
1、聚合是对文档数据的统计、分析、计算聚合的常见种类有哪些？
1、Bucket：对文档数据分组，并统计每组数量2、Metric：对文档数据做计算，例如avg
3、Pipeline：基于其它聚合结果再做聚合
参与聚合的字段类型必须是:
1、keyword
2、数值3、日期
4、布尔
aggs代表聚合，与query同级，此时query的作用是？
1、限定聚合的的文档范围
聚合必须的三要素：1、聚合名称
2、聚合类型3、聚合字段
聚合可配置属性有：1、size：指定聚合结果数量
2、order：指定聚合结果排序方式
3、field：指定聚合字段
如何使用拼音分词器？
1、下载pinyin分词器
2、解压并放到elasticsearch的plugin目录3、重启即可
如何自定义分词器？
1、创建索引库时，在settings中配置，可以包含三部分2、character filter
3、tokenizer4、filter
拼音分词器注意事项？
1、为了避免搜索到同音字，搜索时不要使用拼音分词器
自动补全对字段的要求：
1、类型是completion类型
2、字段值是多词条的数组
方式一：同步调用
1、优点：实现简单，粗暴
2、缺点：业务耦合度高
方式二：异步通知
1、优点：低耦合，实现难度一般2、缺点：依赖mq的可靠性
方式三：监听binlog
1、优点：完全解除服务间耦合
2、缺点：开启biniog增加数据库负担、实现复杂度高
master eligible节点的作用是什么？
1、参与集群选主
2、主节点可以管理集群状态、管理分片信息、处理创建和删除索引库的请求
data节点的作用是什么？1、数据的CRUD
coordinator节点的作用是什么？1、路由请求到其它节点
2、合并查询到的结果，返回给用户
分布式新增如何确定分片？
1、coordinating node根据id做hash运算，得到结果对shard数量取余，余数就是对应的分片
分布式查询：
1、分散阶段: coordinating node将查询请求分发给不同分片2、收集阶段:将查询结果汇总到coordinating node ，整理并返回给用户
故障转移：
1、master宕机后，EligibleMaster选举为新的主节点。
2、master节点监控分片、节点状态，将故障节点上的分片转移到正常节点，确保数据安全。
数据聚合
聚合的分类
聚合（aggregations）可以实现对文档数据的统计、分析、运算
聚合常见的有三类：
桶（Bucket）聚合：用来对文档做分组
1、TermAggregation：按照文档字段值分组
2、Date Histogram：按照日期阶梯分组，例如一周为一组，或者一月为一组度量（Metric）聚合：用以计算一些值，比如：最大值、最小值、平均值等
1、Avg：求平均值
2、Max：求最大值3、Min：求最小值
4、Stats：同时求max、min、avg、sum等
管道（pipeline）聚合：其它聚合的结果为基础做聚合
DSL实现bucket聚合
统计所有数据中的酒店品牌有几种，此时可以根据酒店品牌的名称做聚合
GET /hotel/_search
{
"size": 0, #size：设置size为0，结果中不包含文档，只包含聚合结果
"aggs": { #aggs：定义聚合
"brandAgg": { #brandAgg：给聚合起个名字
"terms": { #terms：聚合的类型，按照品牌值聚合，所以选term
"field": "brand", #field：参与聚合的字段
"size": 20 #size：希望获取的聚合结果数量
}
}
}
}buckets里的doc_count是指该key有多少个
?
默认情况下，Bucket聚合会统计Bucket内的文档数量，记为_count，并且按照_count降序排序?
?GET /hotel/_search
{
? "size": 0,
? "aggs": {
? ? "brandAgg": {
? ? ? "terms": {
? ? ? ? "field": "brand",
? ? ? ? "size": 20,
? ? ? ? "order": {
? ? ? ? ? "_count": "asc"
? ? ? ? }
? ? ? }
? ? }
? }
}此时设置为升序，则右边的数据是升序排序?
?
默认情况下，Bucket聚合是对索引库的所有文档做聚合，我们可以限定要聚合的文档范围，只要添加query条件即可?
GET /hotel/_search
{
"query": {
"range": {
"price": {
"lte": 200
}
}
},
"size": 0,
"aggs": {
"brandAgg": {
"terms": {
"field": "brand",
"size": 20
}
}
}
}此时只会查price小于等于200的数据?
?
DSL实现Metrics聚合
要求获取每个品牌的用户评分的min、max、avg等值
可以利用stats聚合：
GET /hotel/_search
{
"size": 0,
"aggs": {
"brandAgg": {
"terms": {
"field": "brand",
"size": 20,
"order": {
"scoreAgg.avg": "desc"
}
},
"aggs": { #是brands聚合的子集合，也就是分组后对每组分别计算
"scoreAgg": { #聚合名称
"stats": { #聚合类型，这里的stats可以计算min,max,avg等
"field": "score" #聚合字段，这里是score
}
}
}
}
}
}统计出了每个buckets的min,max,avg,sum了?
?
RestAPI实现聚合
请求组装
HotelSearchTest.java
@Test
void testAggregation() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、设置size
request.source().size(0);
//2.2、聚合
request.source().aggregation(AggregationBuilders
.terms("brandAgg")
.field("brand")
.size(10)
);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
Aggregations aggregations = response.getAggregations();
//4.1、根据聚合名称获聚合结果
Terms brandTerms = aggregations.get("brandAgg");
//4.2、获取buckets
List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
//4.3、遍历
for(Terms.Bucket bucket : buckets){
//4.4、获取key
String key = bucket.getKeyAsString();
System.out.println(key);
}
}
package cn.itcast.hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import com.alibaba.fastjson.JSON;
import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.CreateIndexRequest;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.Rewriteable;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.Aggregation;
import org.elasticsearch.search.aggregations.AggregationBuilder;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggester;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.springframework.util.CollectionUtils;
import javax.naming.directory.SearchResult;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import static cn.itcast.hotel.constants.HotelConstants.MAPPING_TEMPLATE;
public class HotelSearchTest {
private RestHighLevelClient client;
@Test
void testMatchAll() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().query(QueryBuilders.matchAllQuery());
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testMatch() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().query(QueryBuilders.matchQuery("all","如家"));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testBool() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、准备booleanQuery
BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
//2.2、添加term
boolQuery.must(QueryBuilders.termQuery("city","上海"));
//2.3、添加range
boolQuery.filter(QueryBuilders.rangeQuery("price").lte(250));
request.source().query(boolQuery);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testRageAndSort() throws IOException {
//页码，每页大小
int page = 2, size = 5;
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、准备query
request.source().query(QueryBuilders.matchAllQuery());
//2.2、排序sort
request.source().sort("price", SortOrder.ASC);
//2.3、分页from,size
request.source().from((page - 1) * size).size(5);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testHighlight() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
request.source().query(QueryBuilders.matchQuery("all","如家"));
//2.2、高亮
request.source().highlighter(new HighlightBuilder().field("name").requireFieldMatch(false));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testAggregation() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、设置size
request.source().size(0);
//2.2、聚合
request.source().aggregation(AggregationBuilders
.terms("brandAgg")
.field("brand")
.size(10)
);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
Aggregations aggregations = response.getAggregations();
//4.1、根据聚合名称获聚合结果
Terms brandTerms = aggregations.get("brandAgg");
//4.2、获取buckets
List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
//4.3、遍历
for(Terms.Bucket bucket : buckets){
//4.4、获取key
String key = bucket.getKeyAsString();
System.out.println(key);
}
}
private void handleResponse(SearchResponse response) {
//4、解析响应
SearchHits searchHits = response.getHits();
//4.1获取总条数
long total = searchHits.getTotalHits().value;
System.out.println("共搜索到" + total + "条数据");
//4.2文档数组
SearchHit[] hits = searchHits.getHits();
//4.3遍历
for (SearchHit hit : hits) {
//获取文档source
String json = hit.getSourceAsString();
//反序列化
HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
//获取高亮结果
Map<String, HighlightField> highlightFields = hit.getHighlightFields();
//判断是否有高亮结果
if(!CollectionUtils.isEmpty(highlightFields)){
//根据字段名获取高亮结果
HighlightField highlightField = highlightFields.get("name");
//判断是否有字段名高亮
if(highlightField != null){
//获取高亮值
String name = highlightField.getFragments()[0].string();
//覆盖非高亮结果
hotelDoc.setName(name);
}
}
System.out.println("hotelDoc = " + hotelDoc);
}
System.out.println(response);
}
@BeforeEach
void setUp() {
this.client = new RestHighLevelClient(RestClient.builder(
HttpHost.create("http://xxx.xxx.xxx.xxx:9200")
));
}
@AfterEach
void tearDown() throws IOException {
this.client.close();
}
}
成功获取到聚合结果?
多条件聚合
IHotelService.java
Map<String, List<String>> filters(RequestParams params);
package cn.itcast.hotel.service;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import com.baomidou.mybatisplus.extension.service.IService;
import java.util.List;
import java.util.Map;
public interface IHotelService extends IService<Hotel> {
PageResult search(RequestParams params);
Map<String, List<String>> filters(RequestParams params);
}
Hotelservice.java
?@Override
? ? public Map<String, List<String>> filters() {
? ? ? ? try {
? ? ? ? ? ? //1、准备Request
? ? ? ? ? ? SearchRequest request = new SearchRequest("hotel");
? ? ? ? ? ? //2、准备DSL
? ? ? ? ? ? //2.2、设置size
? ? ? ? ? ? request.source().size(0);
? ? ? ? ? ? //2.3、聚合
? ? ? ? ? ? buildAggregation(request);
? ? ? ? ? ? //3、发送请求
? ? ? ? ? ? SearchResponse response = client.search(request, RequestOptions.DEFAULT);
? ? ? ? ? ? //4、解析响应
? ? ? ? ? ? Map<String, List<String>> result = new HashMap<>();
? ? ? ? ? ? Aggregations aggregations = response.getAggregations();
? ? ? ? ? ? //4.1、根据品牌名称，获取品牌结果
? ? ? ? ? ? List<String> brandList = getAggByName(aggregations,"brandAgg");
? ? ? ? ? ? result.put("brand",brandList);
? ? ? ? ? ? //4.1、根据城市名称，获取品牌结果
? ? ? ? ? ? List<String> cityList = getAggByName(aggregations,"cityAgg");
? ? ? ? ? ? result.put("city",cityList);
? ? ? ? ? ? //4.1、根据星级名称，获取品牌结果
? ? ? ? ? ? List<String> starList = getAggByName(aggregations,"starAgg");
? ? ? ? ? ? result.put("starName",starList);
? ? ? ? ? ? return result;
? ? ? ? } catch (IOException e) {
? ? ? ? ? ? throw new RuntimeException(e);
? ? ? ? }
? ? }
? ? private void buildAggregation(SearchRequest request) {
? ? ? ? request.source().aggregation(AggregationBuilders
? ? ? ? ? ? ? ? .terms("brandAgg")
? ? ? ? ? ? ? ? .field("brand")
? ? ? ? ? ? ? ? .size(100)
? ? ? ? );
? ? ? ? request.source().aggregation(AggregationBuilders
? ? ? ? ? ? ? ? .terms("cityAgg")
? ? ? ? ? ? ? ? .field("city")
? ? ? ? ? ? ? ? .size(100)
? ? ? ? );
? ? ? ? request.source().aggregation(AggregationBuilders
? ? ? ? ? ? ? ? .terms("starAgg")
? ? ? ? ? ? ? ? .field("starName")
? ? ? ? ? ? ? ? .size(100)
? ? ? ? );
? ? }
?
? ? private void buildBasicQuery(RequestParams params, SearchRequest request) {
? ? ? ? //构建BooleanQuery
? ? ? ? BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
? ? ? ? //关键字搜索
? ? ? ? String key = params.getKey();
? ? ? ? if(key == null || "".equals(key)){
? ? ? ? ? ? boolQuery.must(QueryBuilders.matchAllQuery());
? ? ? ? }else{
? ? ? ? ? ? boolQuery.must(QueryBuilders.matchQuery("all",key));
? ? ? ? }
? ? ? ? //城市条件
? ? ? ? if(params.getCity() != null && !"".equals(params.getCity())){
? ? ? ? ? ? boolQuery.filter(QueryBuilders.termQuery("city", params.getCity()));
? ? ? ? }
? ? ? ? //品牌条件
? ? ? ? if(params.getBrand() != null && !"".equals(params.getBrand())){
? ? ? ? ? ? boolQuery.filter(QueryBuilders.termQuery("brand", params.getBrand()));
? ? ? ? }
? ? ? ? //星级条件
? ? ? ? if(params.getStarName() != null && !"".equals(params.getStarName())){
? ? ? ? ? ? boolQuery.filter(QueryBuilders.termQuery("starName", params.getStarName()));
? ? ? ? }
? ? ? ? //价格
? ? ? ? if(params.getMinPrice() != null && params.getMaxPrice() != null){
? ? ? ? ? ? boolQuery.filter(QueryBuilders.rangeQuery("price").gte(params.getMinPrice()).lte(params.getMaxPrice()));
? ? ? ? }
? ? ? ? request.source().query(functionScoreQueryBuilder);
? ? }
?private List<String> getAggByName(Aggregations aggregations, String aggName) {
? ? ? ? //4.1、根据聚合名称获聚合结果
? ? ? ? Terms brandTerms = aggregations.get(aggName);
? ? ? ? //4.2、获取buckets
? ? ? ? List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
? ? ? ? //4.3、遍历
? ? ? ? List<String> brandList = new ArrayList<>();
? ? ? ? for(Terms.Bucket bucket : buckets){
? ? ? ? ? ? //4.4、获取key
? ? ? ? ? ? String key = bucket.getKeyAsString();
? ? ? ? ? ? brandList.add(key);
? ? ? ? }
? ? ? ? return brandList;
? ? }
? ? private PageResult handleResponse(SearchResponse response) {
? ? ? ? //4、解析响应
? ? ? ? SearchHits searchHits = response.getHits();
? ? ? ? //4.1获取总条数
? ? ? ? long total = searchHits.getTotalHits().value;
? ? ? ? //4.2文档数组
? ? ? ? SearchHit[] hits = searchHits.getHits();
? ? ? ? //4.3遍历
? ? ? ? List<HotelDoc> hotels = new ArrayList<>();
? ? ? ? for (SearchHit hit : hits) {
? ? ? ? ? ? //获取文档source
? ? ? ? ? ? String json = hit.getSourceAsString();
? ? ? ? ? ? //反序列化
? ? ? ? ? ? HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
? ? ? ? ? ? //获取距离
? ? ? ? ? ? Object[] sortValues = hit.getSortValues();
? ? ? ? ? ? if(sortValues.length > 0){
? ? ? ? ? ? ? ? Object sortValue = sortValues[0];
? ? ? ? ? ? ? ? hotelDoc.setDistance(sortValue);
? ? ? ? ? ? }
? ? ? ? ? ? hotels.add(hotelDoc);
? ? ? ? }
? ? ? ? //4、封装返回
? ? ? ? return new PageResult(total,hotels);
? ? }
package cn.itcast.hotel.service.impl;
import cn.itcast.hotel.mapper.HotelMapper;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.apache.lucene.queries.function.FunctionScoreQuery;
import org.apache.lucene.search.vectorhighlight.ScoreOrderFragmentsBuilder;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.geo.GeoPoint;
import org.elasticsearch.common.unit.DistanceUnit;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.functionscore.FunctionScoreQueryBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortBuilders;
import org.elasticsearch.search.sort.SortOrder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Service
public class HotelService extends ServiceImpl<HotelMapper, Hotel> implements IHotelService {
@Autowired
private RestHighLevelClient client;
@Override
public PageResult search(RequestParams params) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
buildBasicQuery(params,request);
//2.2、分页
int page = params.getPage();
int size = params.getSize();
request.source().from((page - 1) * size).size(size);
//2.3、排序
String location = params.getLocation();
if(location != null && !"".equals(location)){
request.source().sort(SortBuilders
.geoDistanceSort("location",new GeoPoint(location))
.order(SortOrder.ASC)
.unit(DistanceUnit.KILOMETERS)
);
}
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
return handleResponse(response);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public Map<String, List<String>> filters() {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.2、设置size
request.source().size(0);
//2.3、聚合
buildAggregation(request);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
Map<String, List<String>> result = new HashMap<>();
Aggregations aggregations = response.getAggregations();
//4.1、根据品牌名称，获取品牌结果
List<String> brandList = getAggByName(aggregations,"brandAgg");
result.put("brand",brandList);
//4.1、根据城市名称，获取品牌结果
List<String> cityList = getAggByName(aggregations,"cityAgg");
result.put("city",cityList);
//4.1、根据星级名称，获取品牌结果
List<String> starList = getAggByName(aggregations,"starAgg");
result.put("starName",starList);
return result;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
private void buildAggregation(SearchRequest request) {
request.source().aggregation(AggregationBuilders
.terms("brandAgg")
.field("brand")
.size(100)
);
request.source().aggregation(AggregationBuilders
.terms("cityAgg")
.field("city")
.size(100)
);
request.source().aggregation(AggregationBuilders
.terms("starAgg")
.field("starName")
.size(100)
);
}
private void buildBasicQuery(RequestParams params, SearchRequest request) {
//构建BooleanQuery
BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
//关键字搜索
String key = params.getKey();
if(key == null || "".equals(key)){
boolQuery.must(QueryBuilders.matchAllQuery());
}else{
boolQuery.must(QueryBuilders.matchQuery("all",key));
}
//城市条件
if(params.getCity() != null && !"".equals(params.getCity())){
boolQuery.filter(QueryBuilders.termQuery("city", params.getCity()));
}
//品牌条件
if(params.getBrand() != null && !"".equals(params.getBrand())){
boolQuery.filter(QueryBuilders.termQuery("brand", params.getBrand()));
}
//星级条件
if(params.getStarName() != null && !"".equals(params.getStarName())){
boolQuery.filter(QueryBuilders.termQuery("starName", params.getStarName()));
}
//价格
if(params.getMinPrice() != null && params.getMaxPrice() != null){
boolQuery.filter(QueryBuilders.rangeQuery("price").gte(params.getMinPrice()).lte(params.getMaxPrice()));
}
request.source().query(functionScoreQueryBuilder);
}
private List<String> getAggByName(Aggregations aggregations, String aggName) {
//4.1、根据聚合名称获聚合结果
Terms brandTerms = aggregations.get(aggName);
//4.2、获取buckets
List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
//4.3、遍历
List<String> brandList = new ArrayList<>();
for(Terms.Bucket bucket : buckets){
//4.4、获取key
String key = bucket.getKeyAsString();
brandList.add(key);
}
return brandList;
}
private PageResult handleResponse(SearchResponse response) {
//4、解析响应
SearchHits searchHits = response.getHits();
//4.1获取总条数
long total = searchHits.getTotalHits().value;
//4.2文档数组
SearchHit[] hits = searchHits.getHits();
//4.3遍历
List<HotelDoc> hotels = new ArrayList<>();
for (SearchHit hit : hits) {
//获取文档source
String json = hit.getSourceAsString();
//反序列化
HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
//获取距离
Object[] sortValues = hit.getSortValues();
if(sortValues.length > 0){
Object sortValue = sortValues[0];
hotelDoc.setDistance(sortValue);
}
hotels.add(hotelDoc);
}
//4、封装返回
return new PageResult(total,hotels);
}
}
HotelDemoApplicationTest.java
@Test
void contextLoads() {
Map<String, List<String>> filters = hotelService.filters();
System.out.println(filters);
}
package cn.itcast.hotel;
import cn.itcast.hotel.service.IHotelService;
import com.fasterxml.jackson.databind.deser.impl.CreatorCandidate;
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.Map;
@SpringBootTest
class HotelDemoApplicationTests {
@Autowired
private IHotelService hotelService;
@Test
void contextLoads() {
Map<String, List<String>> filters = hotelService.filters();
System.out.println(filters);
}
}
多条件聚合成功?
?
带过滤条件的聚合
HotelController.java
@PostMapping("filters")
public Map<String, List<String>> getFilters(@RequestBody RequestParams params){
return hotelService.filters(params);
}
package cn.itcast.hotel.web;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
import java.util.Map;
@RestController
@RequestMapping("/hotel")
public class HotelController {
@Autowired
private IHotelService hotelService;
@PostMapping("/list")
public PageResult search(@RequestBody RequestParams params){
return hotelService.search(params);
}
@PostMapping("filters")
public Map<String, List<String>> getFilters(@RequestBody RequestParams params){
return hotelService.filters(params);
}
}
IHotelService.java
Map<String, List<String>> filters(RequestParams params);
package cn.itcast.hotel.service;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import com.baomidou.mybatisplus.extension.service.IService;
import java.util.List;
import java.util.Map;
public interface IHotelService extends IService<Hotel> {
PageResult search(RequestParams params);
Map<String, List<String>> filters(RequestParams params);
}
HotelService.java
??@Override
? ? public Map<String, List<String>> filters(RequestParams params) {
? ? ? ? try {
? ? ? ? ? ? //1、准备Request
? ? ? ? ? ? SearchRequest request = new SearchRequest("hotel");
? ? ? ? ? ? //2、准备DSL
? ? ? ? ? ? //2.1、query
? ? ? ? ? ? buildBasicQuery(params, request);
? ? ? ? ? ? //2.2、设置size
? ? ? ? ? ? request.source().size(0);
? ? ? ? ? ? //2.3、聚合
? ? ? ? ? ? buildAggregation(request);
? ? ? ? ? ? //3、发送请求
? ? ? ? ? ? SearchResponse response = client.search(request, RequestOptions.DEFAULT);
? ? ? ? ? ? //4、解析响应
? ? ? ? ? ? Map<String, List<String>> result = new HashMap<>();
? ? ? ? ? ? Aggregations aggregations = response.getAggregations();
? ? ? ? ? ? //4.1、根据品牌名称，获取品牌结果
? ? ? ? ? ? List<String> brandList = getAggByName(aggregations,"brandAgg");
? ? ? ? ? ? result.put("brand",brandList);
? ? ? ? ? ? //4.1、根据城市名称，获取品牌结果
? ? ? ? ? ? List<String> cityList = getAggByName(aggregations,"cityAgg");
? ? ? ? ? ? result.put("city",cityList);
? ? ? ? ? ? //4.1、根据星级名称，获取品牌结果
? ? ? ? ? ? List<String> starList = getAggByName(aggregations,"starAgg");
? ? ? ? ? ? result.put("starName",starList);
? ? ? ? ? ? return result;
? ? ? ? } catch (IOException e) {
? ? ? ? ? ? throw new RuntimeException(e);
? ? ? ? }
? ? }
? ? private void buildAggregation(SearchRequest request) {
? ? ? ? request.source().aggregation(AggregationBuilders
? ? ? ? ? ? ? ? .terms("brandAgg")
? ? ? ? ? ? ? ? .field("brand")
? ? ? ? ? ? ? ? .size(100)
? ? ? ? );
? ? ? ? request.source().aggregation(AggregationBuilders
? ? ? ? ? ? ? ? .terms("cityAgg")
? ? ? ? ? ? ? ? .field("city")
? ? ? ? ? ? ? ? .size(100)
? ? ? ? );
? ? ? ? request.source().aggregation(AggregationBuilders
? ? ? ? ? ? ? ? .terms("starAgg")
? ? ? ? ? ? ? ? .field("starName")
? ? ? ? ? ? ? ? .size(100)
? ? ? ? );
? ? }
?
? ? private void buildBasicQuery(RequestParams params, SearchRequest request) {
? ? ? ? //构建BooleanQuery
? ? ? ? BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
? ? ? ? //关键字搜索
? ? ? ? String key = params.getKey();
? ? ? ? if(key == null || "".equals(key)){
? ? ? ? ? ? boolQuery.must(QueryBuilders.matchAllQuery());
? ? ? ? }else{
? ? ? ? ? ? boolQuery.must(QueryBuilders.matchQuery("all",key));
? ? ? ? }
? ? ? ? //城市条件
? ? ? ? if(params.getCity() != null && !"".equals(params.getCity())){
? ? ? ? ? ? boolQuery.filter(QueryBuilders.termQuery("city", params.getCity()));
? ? ? ? }
? ? ? ? //品牌条件
? ? ? ? if(params.getBrand() != null && !"".equals(params.getBrand())){
? ? ? ? ? ? boolQuery.filter(QueryBuilders.termQuery("brand", params.getBrand()));
? ? ? ? }
? ? ? ? //星级条件
? ? ? ? if(params.getStarName() != null && !"".equals(params.getStarName())){
? ? ? ? ? ? boolQuery.filter(QueryBuilders.termQuery("starName", params.getStarName()));
? ? ? ? }
? ? ? ? //价格
? ? ? ? if(params.getMinPrice() != null && params.getMaxPrice() != null){
? ? ? ? ? ? boolQuery.filter(QueryBuilders.rangeQuery("price").gte(params.getMinPrice()).lte(params.getMaxPrice()));
? ? ? ? }
? ? ? ? request.source().query(functionScoreQueryBuilder);
? ? }
?private List<String> getAggByName(Aggregations aggregations, String aggName) {
? ? ? ? //4.1、根据聚合名称获聚合结果
? ? ? ? Terms brandTerms = aggregations.get(aggName);
? ? ? ? //4.2、获取buckets
? ? ? ? List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
? ? ? ? //4.3、遍历
? ? ? ? List<String> brandList = new ArrayList<>();
? ? ? ? for(Terms.Bucket bucket : buckets){
? ? ? ? ? ? //4.4、获取key
? ? ? ? ? ? String key = bucket.getKeyAsString();
? ? ? ? ? ? brandList.add(key);
? ? ? ? }
? ? ? ? return brandList;
? ? }
? ? private PageResult handleResponse(SearchResponse response) {
? ? ? ? //4、解析响应
? ? ? ? SearchHits searchHits = response.getHits();
? ? ? ? //4.1获取总条数
? ? ? ? long total = searchHits.getTotalHits().value;
? ? ? ? //4.2文档数组
? ? ? ? SearchHit[] hits = searchHits.getHits();
? ? ? ? //4.3遍历
? ? ? ? List<HotelDoc> hotels = new ArrayList<>();
? ? ? ? for (SearchHit hit : hits) {
? ? ? ? ? ? //获取文档source
? ? ? ? ? ? String json = hit.getSourceAsString();
? ? ? ? ? ? //反序列化
? ? ? ? ? ? HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
? ? ? ? ? ? //获取距离
? ? ? ? ? ? Object[] sortValues = hit.getSortValues();
? ? ? ? ? ? if(sortValues.length > 0){
? ? ? ? ? ? ? ? Object sortValue = sortValues[0];
? ? ? ? ? ? ? ? hotelDoc.setDistance(sortValue);
? ? ? ? ? ? }
? ? ? ? ? ? hotels.add(hotelDoc);
? ? ? ? }
? ? ? ? //4、封装返回
? ? ? ? return new PageResult(total,hotels);
? ? }
package cn.itcast.hotel.service.impl;
import cn.itcast.hotel.mapper.HotelMapper;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.apache.lucene.queries.function.FunctionScoreQuery;
import org.apache.lucene.search.vectorhighlight.ScoreOrderFragmentsBuilder;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.geo.GeoPoint;
import org.elasticsearch.common.unit.DistanceUnit;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.functionscore.FunctionScoreQueryBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortBuilders;
import org.elasticsearch.search.sort.SortOrder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Service
public class HotelService extends ServiceImpl<HotelMapper, Hotel> implements IHotelService {
@Autowired
private RestHighLevelClient client;
@Override
public PageResult search(RequestParams params) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
buildBasicQuery(params,request);
//2.2、分页
int page = params.getPage();
int size = params.getSize();
request.source().from((page - 1) * size).size(size);
//2.3、排序
String location = params.getLocation();
if(location != null && !"".equals(location)){
request.source().sort(SortBuilders
.geoDistanceSort("location",new GeoPoint(location))
.order(SortOrder.ASC)
.unit(DistanceUnit.KILOMETERS)
);
}
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
return handleResponse(response);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public Map<String, List<String>> filters(RequestParams params) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
buildBasicQuery(params, request);
//2.2、设置size
request.source().size(0);
//2.3、聚合
buildAggregation(request);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
Map<String, List<String>> result = new HashMap<>();
Aggregations aggregations = response.getAggregations();
//4.1、根据品牌名称，获取品牌结果
List<String> brandList = getAggByName(aggregations,"brandAgg");
result.put("brand",brandList);
//4.1、根据城市名称，获取品牌结果
List<String> cityList = getAggByName(aggregations,"cityAgg");
result.put("city",cityList);
//4.1、根据星级名称，获取品牌结果
List<String> starList = getAggByName(aggregations,"starAgg");
result.put("starName",starList);
return result;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
private void buildAggregation(SearchRequest request) {
request.source().aggregation(AggregationBuilders
.terms("brandAgg")
.field("brand")
.size(100)
);
request.source().aggregation(AggregationBuilders
.terms("cityAgg")
.field("city")
.size(100)
);
request.source().aggregation(AggregationBuilders
.terms("starAgg")
.field("starName")
.size(100)
);
}
private void buildBasicQuery(RequestParams params, SearchRequest request) {
//构建BooleanQuery
BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
//关键字搜索
String key = params.getKey();
if(key == null || "".equals(key)){
boolQuery.must(QueryBuilders.matchAllQuery());
}else{
boolQuery.must(QueryBuilders.matchQuery("all",key));
}
//城市条件
if(params.getCity() != null && !"".equals(params.getCity())){
boolQuery.filter(QueryBuilders.termQuery("city", params.getCity()));
}
//品牌条件
if(params.getBrand() != null && !"".equals(params.getBrand())){
boolQuery.filter(QueryBuilders.termQuery("brand", params.getBrand()));
}
//星级条件
if(params.getStarName() != null && !"".equals(params.getStarName())){
boolQuery.filter(QueryBuilders.termQuery("starName", params.getStarName()));
}
//价格
if(params.getMinPrice() != null && params.getMaxPrice() != null){
boolQuery.filter(QueryBuilders.rangeQuery("price").gte(params.getMinPrice()).lte(params.getMaxPrice()));
}
request.source().query(functionScoreQueryBuilder);
}
private List<String> getAggByName(Aggregations aggregations, String aggName) {
//4.1、根据聚合名称获聚合结果
Terms brandTerms = aggregations.get(aggName);
//4.2、获取buckets
List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
//4.3、遍历
List<String> brandList = new ArrayList<>();
for(Terms.Bucket bucket : buckets){
//4.4、获取key
String key = bucket.getKeyAsString();
brandList.add(key);
}
return brandList;
}
private PageResult handleResponse(SearchResponse response) {
//4、解析响应
SearchHits searchHits = response.getHits();
//4.1获取总条数
long total = searchHits.getTotalHits().value;
//4.2文档数组
SearchHit[] hits = searchHits.getHits();
//4.3遍历
List<HotelDoc> hotels = new ArrayList<>();
for (SearchHit hit : hits) {
//获取文档source
String json = hit.getSourceAsString();
//反序列化
HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
//获取距离
Object[] sortValues = hit.getSortValues();
if(sortValues.length > 0){
Object sortValue = sortValues[0];
hotelDoc.setDistance(sortValue);
}
hotels.add(hotelDoc);
}
//4、封装返回
return new PageResult(total,hotels);
}
}
此时，只要使用条件，就会影响到其他的条件。比如选择某个地点，或输入某个品牌，就会减少一些条件。例如：选择100-300元，就不会出现五星级
?
自动补全
安装拼音分词器
py
https://pan.baidu.com/s/1gPkxVU6dJL7mRVaPYwNmYQ?pwd=hano
把该文件夹放到/var/lib/docker/volumes/es-plugins/_data目录下?
?
自定义分词器
elasticsearch中分词器(analyzer)的组成包含三部分
1、character filters：在tokenizer之前对文本进行处理。例如删除字符、替换字符
2、tokenizer：将文本按照一定的规则切割成词条(term)。例如keyword，就是不分词；还有ik_smart
3、tokenizer filter：将tokenizer输出的词条做进一步处理。例如大小写转换、同义词处理、拼音处理等?
我们可以在创建索引库时，通过settings来配置自定义的analyzer(分词器)?
PUT /test
{
"settings": {
"analysis": {
"analyzer": {
"my_analyzer": {
"tokenizer": "ik_max_word",
"filter": "py"
}
},
"filter": {
"py": {
"type": "pinyin",
"keep_full_pinyin": false,
"keep_joined_full_pinyin": true,
"keep_original": true,
"limit_first_letter_length": 16,
"remove_duplicated_term": true,
"none_chinese_pinyin_tokenize": false
}
}
}
},
"mappings": {
"properties": {
"name": {
"type": "text",
"analyzer": "my_analyzer",
}
}
}
}创建成功?
?
可以看到，汉字、拼音、拼音首字母的类型都有?
?
拼音分词器适合在创建倒排索引的时候使用，但不能在搜索的时候使用。
这里创建两条倒排索引，并搜索第三条命令
POST /test/_doc/1
{
"id": 1,
"name": "狮子"
}
POST /test/_doc/2
{
"id": 2,
"name": "虱子"
}
GET /test/_search
{
"query": {
"match": {
"name": "掉入狮子笼咋办"
}
}
}此时会发现两个shizi都搜索到了?
?
因此字段在创建倒排索引时应该用my_analyzer分词器;字段在搜索时应该使用ik_smart分词器?
PUT /test
{
"settings": {
"analysis": {
"analyzer": {
"my_analyzer": {
"tokenizer": "ik_max_word",
"filter": "py"
}
},
"filter": {
"py": {
"type": "pinyin",
"keep_full_pinyin": false,
"keep_joined_full_pinyin": true,
"keep_original": true,
"limit_first_letter_length": 16,
"remove_duplicated_term": true,
"none_chinese_pinyin_tokenize": false
}
}
}
},
"mappings": {
"properties": {
"name": {
"type": "text",
"analyzer": "my_analyzer",
"search_analyzer": "ik_smart"
}
}
}
}再次创建这两个倒排索引，查询第三条命令
POST /test/_doc/1
{
"id": 1,
"name": "狮子"
}
POST /test/_doc/2
{
"id": 2,
"name": "虱子"
}
GET /test/_search
{
"query": {
"match": {
"name": "掉入狮子笼咋办"
}
}
}此时发现，同音字问题解决了?
?
completion suggester查询
elasticsearch提供了Completion Suggester查询来实现自动补全功能。这个查询会匹配以用户输入内容开头的词条并返回。为了提高补全查询的效率，对于文档中字段的类型有一些约束：
1、参与补全查询的字段必须是completion类型。
2、字段的内容一般是用来补全的多个词条形成的数组。
创建索引库
PUT test2
{
"mappings": {
"properties": {
"title": {
"type": "completion"
}
}
}
}插入三条数据
POST test2/_doc
{
"title": ["Sony","WH-1000XM3"]
}
POST test2/_doc
{
"title": ["SK-II","PITERA"]
}
POST test2/_doc
{
"title": ["Nintendo","switch"]
}自动补全查询
GET /test2/_search
{
"suggest": {
"titleSuggest": {
"text": "s",
"completion": {
"field": "title",
"skip_duplicates": true,
"size": 10
}
}
}
}可以看到，所以我只搜了s，但是S开头的数据都查询到了?
?
修改索引库数据结构
创建索引库
PUT /hotel
{
"settings": {
"analysis": {
"analyzer": {
"text_anlyzer": {
"tokenizer": "ik_max_word",
"filter": "py"
},
"completion_analyzer": {
"tokenizer": "keyword",
"filter": "py"
}
},
"filter": {
"py": {
"type": "pinyin",
"keep_full_pinyin": false,
"keep_joined_full_pinyin": true,
"keep_original": true,
"limit_first_letter_length": 16,
"remove_duplicated_term": true,
"none_chinese_pinyin_tokenize": false
}
}
}
},
"mappings": {
"properties": {
"id":{
"type": "keyword"
},
"name":{
"type": "text",
"analyzer": "text_anlyzer",
"search_analyzer": "ik_smart",
"copy_to": "all"
},
"address":{
"type": "keyword",
"index": false
},
"price":{
"type": "integer"
},
"score":{
"type": "integer"
},
"brand":{
"type": "keyword",
"copy_to": "all"
},
"city":{
"type": "keyword"
},
"starName":{
"type": "keyword"
},
"business":{
"type": "keyword",
"copy_to": "all"
},
"location":{
"type": "geo_point"
},
"pic":{
"type": "keyword",
"index": false
},
"all":{
"type": "text",
"analyzer": "text_anlyzer",
"search_analyzer": "ik_smart"
},
"suggestion":{
"type": "completion",
"analyzer": "completion_analyzer"
}
}
}
}HotelDoc.java
package cn.itcast.hotel.pojo;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.util.*;
@Data
@NoArgsConstructor
public class HotelDoc {
private Long id;
private String name;
private String address;
private Integer price;
private Integer score;
private String brand;
private String city;
private String starName;
private String business;
private String location;
private String pic;
private Object distance;
private Boolean isAD;
private List<String> suggestion;
public HotelDoc(Hotel hotel) {
this.id = hotel.getId();
this.name = hotel.getName();
this.address = hotel.getAddress();
this.price = hotel.getPrice();
this.score = hotel.getScore();
this.brand = hotel.getBrand();
this.city = hotel.getCity();
this.starName = hotel.getStarName();
this.business = hotel.getBusiness();
this.location = hotel.getLatitude() + ", " + hotel.getLongitude();
this.pic = hotel.getPic();
if(this.business.contains("、")){
// business有多个值，需要切割
String[] arr = this.business.split("、");
//添加元素
this.suggestion = new ArrayList<>();
this.suggestion.add(this.brand);
Collections.addAll(this.suggestion,arr);
}else {
this.suggestion = Arrays.asList(this.brand, this.business);
}
}
}
运行HotelDocmentTest.java的testBulkRequest()
@Test
void testBulkRequest() throws IOException {
//批量查询酒店数据
List<Hotel> hotels = hotelService.list();
//1、创建Request
BulkRequest request = new BulkRequest();
//2、准备参数，添加多个新增的Request
for(Hotel hotel:hotels){
//转换为文档类型HotelDoc
HotelDoc hotelDoc = new HotelDoc(hotel);
//创建新增文档的Request对象
request.add(new IndexRequest("hotel")
.id(hotelDoc.getId().toString())
.source(JSON.toJSONString(hotelDoc),XContentType.JSON));
}
//3、发送请求
client.bulk(request,RequestOptions.DEFAULT);
}
测试自动补全
GET /hotel/_search
{
"suggest": {
"suggestions": {
"text": "sd",
"completion": {
"field": "suggestion",
"skip_duplicates": true,
"size": 10
}
}
}
}可以看到自动补全成功。只输入sd能把所有sd开头的text和s开头加d开头的text的数据查询出来
?
RestAPI实现自动补全查询
@Test
void testSuggest() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().suggest(new SuggestBuilder().addSuggestion(
"suggestions",
SuggestBuilders.completionSuggestion("suggestion")
.prefix("h")
.skipDuplicates(true)
.size(10)
));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析结果
Suggest suggest = response.getSuggest();
//4.1、根据补全查询名称，获取补全结果
CompletionSuggestion suggestions = suggest.getSuggestion("suggestions");
//4.2、获取options
List<CompletionSuggestion.Entry.Option> options = suggestions.getOptions();
//4.3、遍历
for(CompletionSuggestion.Entry.Option option : options) {
String text = option.getText().toString();
System.out.println(text);
}
}
package cn.itcast.hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import com.alibaba.fastjson.JSON;
import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.CreateIndexRequest;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.Rewriteable;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.Aggregation;
import org.elasticsearch.search.aggregations.AggregationBuilder;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggester;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.springframework.util.CollectionUtils;
import javax.naming.directory.SearchResult;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import static cn.itcast.hotel.constants.HotelConstants.MAPPING_TEMPLATE;
public class HotelSearchTest {
private RestHighLevelClient client;
@Test
void testMatchAll() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().query(QueryBuilders.matchAllQuery());
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testMatch() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().query(QueryBuilders.matchQuery("all","如家"));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testBool() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、准备booleanQuery
BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
//2.2、添加term
boolQuery.must(QueryBuilders.termQuery("city","上海"));
//2.3、添加range
boolQuery.filter(QueryBuilders.rangeQuery("price").lte(250));
request.source().query(boolQuery);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testRageAndSort() throws IOException {
//页码，每页大小
int page = 2, size = 5;
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、准备query
request.source().query(QueryBuilders.matchAllQuery());
//2.2、排序sort
request.source().sort("price", SortOrder.ASC);
//2.3、分页from,size
request.source().from((page - 1) * size).size(5);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testHighlight() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
request.source().query(QueryBuilders.matchQuery("all","如家"));
//2.2、高亮
request.source().highlighter(new HighlightBuilder().field("name").requireFieldMatch(false));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
handleResponse(response);
}
@Test
void testAggregation() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、设置size
request.source().size(0);
//2.2、聚合
request.source().aggregation(AggregationBuilders
.terms("brandAgg")
.field("brand")
.size(10)
);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
Aggregations aggregations = response.getAggregations();
//4.1、根据聚合名称获聚合结果
Terms brandTerms = aggregations.get("brandAgg");
//4.2、获取buckets
List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
//4.3、遍历
for(Terms.Bucket bucket : buckets){
//4.4、获取key
String key = bucket.getKeyAsString();
System.out.println(key);
}
}
@Test
void testSuggest() throws IOException {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().suggest(new SuggestBuilder().addSuggestion(
"suggestions",
SuggestBuilders.completionSuggestion("suggestion")
.prefix("h")
.skipDuplicates(true)
.size(10)
));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析结果
Suggest suggest = response.getSuggest();
//4.1、根据补全查询名称，获取补全结果
CompletionSuggestion suggestions = suggest.getSuggestion("suggestions");
//4.2、获取options
List<CompletionSuggestion.Entry.Option> options = suggestions.getOptions();
//4.3、遍历
for(CompletionSuggestion.Entry.Option option : options) {
String text = option.getText().toString();
System.out.println(text);
}
}
private void handleResponse(SearchResponse response) {
//4、解析响应
SearchHits searchHits = response.getHits();
//4.1获取总条数
long total = searchHits.getTotalHits().value;
System.out.println("共搜索到" + total + "条数据");
//4.2文档数组
SearchHit[] hits = searchHits.getHits();
//4.3遍历
for (SearchHit hit : hits) {
//获取文档source
String json = hit.getSourceAsString();
//反序列化
HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
//获取高亮结果
Map<String, HighlightField> highlightFields = hit.getHighlightFields();
//判断是否有高亮结果
if(!CollectionUtils.isEmpty(highlightFields)){
//根据字段名获取高亮结果
HighlightField highlightField = highlightFields.get("name");
//判断是否有字段名高亮
if(highlightField != null){
//获取高亮值
String name = highlightField.getFragments()[0].string();
//覆盖非高亮结果
hotelDoc.setName(name);
}
}
System.out.println("hotelDoc = " + hotelDoc);
}
System.out.println(response);
}
@BeforeEach
void setUp() {
this.client = new RestHighLevelClient(RestClient.builder(
HttpHost.create("http://192.168.80.130:9200")
));
}
@AfterEach
void tearDown() throws IOException {
this.client.close();
}
}
可以看到，只查询h，就能查到h开头的数据?
?
实现搜索框自动补全
HotelController.java
? ? @GetMapping("suggestion")
? ? public List<String> getSuggestions(@RequestParam("key")String prefix){
? ? ? ? return hotelService.getSuggestions(prefix);
? ? }
package cn.itcast.hotel.web;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
import java.util.Map;
@RestController
@RequestMapping("/hotel")
public class HotelController {
@Autowired
private IHotelService hotelService;
@PostMapping("/list")
public PageResult search(@RequestBody RequestParams params){
return hotelService.search(params);
}
@PostMapping("filters")
public Map<String, List<String>> getFilters(@RequestBody RequestParams params){
return hotelService.filters(params);
}
@GetMapping("suggestion")
public List<String> getSuggestions(@RequestParam("key")String prefix){
return hotelService.getSuggestions(prefix);
}
}
IHotelService.java
?List<String> getSuggestions(String prefix);
package cn.itcast.hotel.service;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import com.baomidou.mybatisplus.extension.service.IService;
import java.util.List;
import java.util.Map;
public interface IHotelService extends IService<Hotel> {
PageResult search(RequestParams params);
Map<String, List<String>> filters(RequestParams params);
List<String> getSuggestions(String prefix);
}
HotelService.java
@Override
public List<String> getSuggestions(String prefix) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().suggest(new SuggestBuilder().addSuggestion(
"suggestions",
SuggestBuilders.completionSuggestion("suggestion")
.prefix(prefix)
.skipDuplicates(true)
.size(10)
));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析结果
Suggest suggest = response.getSuggest();
//4.1、根据补全查询名称，获取补全结果
CompletionSuggestion suggestions = suggest.getSuggestion("suggestions");
//4.2、获取options
List<CompletionSuggestion.Entry.Option> options = suggestions.getOptions();
//4.3、遍历
List<String> list = new ArrayList<>(options.size());
for(CompletionSuggestion.Entry.Option option : options) {
String text = option.getText().toString();
list.add(text);
}
return list;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
package cn.itcast.hotel.service.impl;
import cn.itcast.hotel.mapper.HotelMapper;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.apache.lucene.queries.function.FunctionScoreQuery;
import org.apache.lucene.search.vectorhighlight.ScoreOrderFragmentsBuilder;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.geo.GeoPoint;
import org.elasticsearch.common.unit.DistanceUnit;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.functionscore.FunctionScoreQueryBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortBuilders;
import org.elasticsearch.search.sort.SortOrder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Service
public class HotelService extends ServiceImpl<HotelMapper, Hotel> implements IHotelService {
@Autowired
private RestHighLevelClient client;
@Override
public PageResult search(RequestParams params) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
buildBasicQuery(params,request);
//2.2、分页
int page = params.getPage();
int size = params.getSize();
request.source().from((page - 1) * size).size(size);
//2.3、排序
String location = params.getLocation();
if(location != null && !"".equals(location)){
request.source().sort(SortBuilders
.geoDistanceSort("location",new GeoPoint(location))
.order(SortOrder.ASC)
.unit(DistanceUnit.KILOMETERS)
);
}
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
return handleResponse(response);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public Map<String, List<String>> filters(RequestParams params) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
buildBasicQuery(params, request);
//2.2、设置size
request.source().size(0);
//2.3、聚合
buildAggregation(request);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
Map<String, List<String>> result = new HashMap<>();
Aggregations aggregations = response.getAggregations();
//4.1、根据品牌名称，获取品牌结果
List<String> brandList = getAggByName(aggregations,"brandAgg");
result.put("brand",brandList);
//4.1、根据城市名称，获取品牌结果
List<String> cityList = getAggByName(aggregations,"cityAgg");
result.put("city",cityList);
//4.1、根据星级名称，获取品牌结果
List<String> starList = getAggByName(aggregations,"starAgg");
result.put("starName",starList);
return result;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public List<String> getSuggestions(String prefix) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().suggest(new SuggestBuilder().addSuggestion(
"suggestions",
SuggestBuilders.completionSuggestion("suggestion")
.prefix(prefix)
.skipDuplicates(true)
.size(10)
));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析结果
Suggest suggest = response.getSuggest();
//4.1、根据补全查询名称，获取补全结果
CompletionSuggestion suggestions = suggest.getSuggestion("suggestions");
//4.2、获取options
List<CompletionSuggestion.Entry.Option> options = suggestions.getOptions();
//4.3、遍历
List<String> list = new ArrayList<>(options.size());
for(CompletionSuggestion.Entry.Option option : options) {
String text = option.getText().toString();
list.add(text);
}
return list;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
private List<String> getAggByName(Aggregations aggregations, String aggName) {
//4.1、根据聚合名称获聚合结果
Terms brandTerms = aggregations.get(aggName);
//4.2、获取buckets
List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
//4.3、遍历
List<String> brandList = new ArrayList<>();
for(Terms.Bucket bucket : buckets){
//4.4、获取key
String key = bucket.getKeyAsString();
brandList.add(key);
}
return brandList;
}
private void buildAggregation(SearchRequest request) {
request.source().aggregation(AggregationBuilders
.terms("brandAgg")
.field("brand")
.size(100)
);
request.source().aggregation(AggregationBuilders
.terms("cityAgg")
.field("city")
.size(100)
);
request.source().aggregation(AggregationBuilders
.terms("starAgg")
.field("starName")
.size(100)
);
}
private void buildBasicQuery(RequestParams params, SearchRequest request) {
//构建BooleanQuery
BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
//关键字搜索
String key = params.getKey();
if(key == null || "".equals(key)){
boolQuery.must(QueryBuilders.matchAllQuery());
}else{
boolQuery.must(QueryBuilders.matchQuery("all",key));
}
//城市条件
if(params.getCity() != null && !"".equals(params.getCity())){
boolQuery.filter(QueryBuilders.termQuery("city", params.getCity()));
}
//品牌条件
if(params.getBrand() != null && !"".equals(params.getBrand())){
boolQuery.filter(QueryBuilders.termQuery("brand", params.getBrand()));
}
//星级条件
if(params.getStarName() != null && !"".equals(params.getStarName())){
boolQuery.filter(QueryBuilders.termQuery("starName", params.getStarName()));
}
//价格
if(params.getMinPrice() != null && params.getMaxPrice() != null){
boolQuery.filter(QueryBuilders.rangeQuery("price").gte(params.getMinPrice()).lte(params.getMaxPrice()));
}
request.source().query(functionScoreQueryBuilder);
}
private PageResult handleResponse(SearchResponse response) {
//4、解析响应
SearchHits searchHits = response.getHits();
//4.1获取总条数
long total = searchHits.getTotalHits().value;
//4.2文档数组
SearchHit[] hits = searchHits.getHits();
//4.3遍历
List<HotelDoc> hotels = new ArrayList<>();
for (SearchHit hit : hits) {
//获取文档source
String json = hit.getSourceAsString();
//反序列化
HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
//获取距离
Object[] sortValues = hit.getSortValues();
if(sortValues.length > 0){
Object sortValue = sortValues[0];
hotelDoc.setDistance(sortValue);
}
hotels.add(hotelDoc);
}
//4、封装返回
return new PageResult(total,hotels);
}
}
在搜索框输入x，可以看到出现自动补全
?
数据同步
数据同步问题分析
elasticsearch中的酒店数据来自于mysql数据库，因此mysql数据发生改变时，elasticsearch也必须跟着改变，这个就是elasticsearch与mysql之间的数据同步。
方案一：同步调用
方案二：异步调用
方案三：监听binlog
导入Hotel-admin
Hotel-adminhttps://pan.baidu.com/s/1lS-PUGaqUWdHEeGHkNrR0w?pwd=5vxx
声明队列和交换机?
在hotel-demo的pom文件
<!--amqp-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-amqp</artifactId>
</dependency>
<?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 https://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>2.3.10.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>cn.itcast.hotel</groupId>
<artifactId>hotel-admin</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>hotel-admin</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.4.2</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
<!--amqp-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-amqp</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>
</project>
在hotel-demo的application.yaml文件
rabbitmq: host: xxx.xxx.xxx.xxx port: 5672 username: itcast password: 123321 virtual-host: /
server:
port: 8099
spring:
datasource:
url: jdbc:mysql://localhost:3306/heima?useSSL=false
username: root
password: 1234
driver-class-name: com.mysql.jdbc.Driver
rabbitmq:
host: xxx.xxx.xxx.xxx
port: 5672
username: itcast
password: 123321
virtual-host: /
logging:
level:
cn.itcast: debug
pattern:
dateformat: MM-dd HH:mm:ss:SSS
mybatis-plus:
configuration:
map-underscore-to-camel-case: true
type-aliases-package: cn.itcast.hotel.pojo在hotel-demo的constants包创建MqConstants.java
package cn.itcast.hotel.constants;
public class MqConstants {
//交换机
public final static String HOTEL_EXCHANGE = "hotel.topic";
//监听新增和修改的队列
public final static String HOTEL_INSERT_QUEUE = "hotel.insert.queue";
//监听删除的队列
public final static String HOTEL_DELETE_QUEUE = "hotel.delete.queue";
//新增或修改的RoutingKey
public final static String HOTEL_INSERT_KEY = "hotel.insert";
//删除的RoutingKey
public final static String HOTEL_DELETE_KEY = "hotel.delete";
}
在hotel-demo创建config包创建MqConfig.java
package cn.itcast.hotel.config;
import cn.itcast.hotel.constants.MqConstants;
import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.Queue;
import org.springframework.amqp.core.TopicExchange;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class MqConfig {
@Bean
public TopicExchange topicExchange(){
return new TopicExchange(MqConstants.HOTEL_EXCHANGE,true,true);
}
@Bean
public Queue insertQueue(){
return new Queue(MqConstants.HOTEL_INSERT_QUEUE,true);
}
@Bean
public Queue deleteQueue(){
return new Queue(MqConstants.HOTEL_DELETE_QUEUE,true);
}
@Bean
public Binding insertQueueBinding(){
return BindingBuilder.bind(insertQueue()).to(topicExchange()).with(MqConstants.HOTEL_INSERT_KEY);
}
@Bean
public Binding deleteQueueBinding(){
return BindingBuilder.bind(deleteQueue()).to(topicExchange()).with(MqConstants.HOTEL_DELETE_KEY);
}
}
发送mq消息
在hotel-admin创建constants包，并把hotel-demo的MqConstants.java复制过来
package cn.itcast.hotel.constants;
public class MqConstants {
//交换机
public final static String HOTEL_EXCHANGE = "hotel.topic";
//监听新增和修改的队列
public final static String HOTEL_INSERT_QUEUE = "hotel.insert.queue";
//监听删除的队列
public final static String HOTEL_DELETE_QUEUE = "hotel.delete.queue";
//新增或修改的RoutingKey
public final static String HOTEL_INSERT_KEY = "hotel.insert";
//删除的RoutingKey
public final static String HOTEL_DELETE_KEY = "hotel.delete";
}
在hotel-admin的pom文件
<!--amqp-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-amqp</artifactId>
</dependency>
<?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 https://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>2.3.10.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>cn.itcast.hotel</groupId>
<artifactId>hotel-admin</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>hotel-admin</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.4.2</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
<!--amqp-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-amqp</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>
</project>
在hotel-admin的application.yaml文件
rabbitmq: host: xxx.xxx.xxx.xxx port: 5672 username: itcast password: 123321 virtual-host: /
server:
port: 8099
spring:
datasource:
url: jdbc:mysql://localhost:3306/heima?useSSL=false
username: root
password: 1234
driver-class-name: com.mysql.jdbc.Driver
rabbitmq:
host: xxx.xxx.xxx.xxx
port: 5672
username: itcast
password: 123321
virtual-host: /
logging:
level:
cn.itcast: debug
pattern:
dateformat: MM-dd HH:mm:ss:SSS
mybatis-plus:
configuration:
map-underscore-to-camel-case: true
type-aliases-package: cn.itcast.hotel.pojo在hotel-admin的HotelController.java
@PostMapping
public void saveHotel(@RequestBody Hotel hotel){
hotelService.save(hotel);
rabbitTemplate.convertAndSend(MqConstants.HOTEL_EXCHANGE,MqConstants.HOTEL_INSERT_KEY,hotel.getId());
}
@PutMapping()
public void updateById(@RequestBody Hotel hotel){
if (hotel.getId() == null) {
throw new InvalidParameterException("id不能为空");
}
hotelService.updateById(hotel);
rabbitTemplate.convertAndSend(MqConstants.HOTEL_EXCHANGE,MqConstants.HOTEL_INSERT_KEY,hotel.getId());
}
@DeleteMapping("/{id}")
public void deleteById(@PathVariable("id") Long id) {
hotelService.removeById(id);
rabbitTemplate.convertAndSend(MqConstants.HOTEL_EXCHANGE,MqConstants.HOTEL_DELETE_KEY,id);
}
package cn.itcast.hotel.web;
import cn.itcast.hotel.constants.MqConstants;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.service.IHotelService;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.security.InvalidParameterException;
@RestController
@RequestMapping("hotel")
public class HotelController {
@Autowired
private IHotelService hotelService;
@Autowired
private RabbitTemplate rabbitTemplate;
@GetMapping("/{id}")
public Hotel queryById(@PathVariable("id") Long id){
return hotelService.getById(id);
}
@GetMapping("/list")
public PageResult hotelList(
@RequestParam(value = "page", defaultValue = "1") Integer page,
@RequestParam(value = "size", defaultValue = "1") Integer size
){
Page<Hotel> result = hotelService.page(new Page<>(page, size));
return new PageResult(result.getTotal(), result.getRecords());
}
@PostMapping
public void saveHotel(@RequestBody Hotel hotel){
hotelService.save(hotel);
rabbitTemplate.convertAndSend(MqConstants.HOTEL_EXCHANGE,MqConstants.HOTEL_INSERT_KEY,hotel.getId());
}
@PutMapping()
public void updateById(@RequestBody Hotel hotel){
if (hotel.getId() == null) {
throw new InvalidParameterException("id不能为空");
}
hotelService.updateById(hotel);
rabbitTemplate.convertAndSend(MqConstants.HOTEL_EXCHANGE,MqConstants.HOTEL_INSERT_KEY,hotel.getId());
}
@DeleteMapping("/{id}")
public void deleteById(@PathVariable("id") Long id) {
hotelService.removeById(id);
rabbitTemplate.convertAndSend(MqConstants.HOTEL_EXCHANGE,MqConstants.HOTEL_DELETE_KEY,id);
}
}
监听MQ消息
在hotel-demo创建mq包创建HotelListener.java
//监听酒店新增和修改的业务
@RabbitListener(queues = MqConstants.HOTEL_INSERT_QUEUE)
public void listenHotelInsertOrUpdate(Long id){
hotelService.insertById(id);
}
//监听酒店删除的业务
@RabbitListener(queues = MqConstants.HOTEL_DELETE_QUEUE)
public void listenHotelDelete(Long id){
hotelService.deleteById(id);
}
package cn.itcast.hotel.mq;
import cn.itcast.hotel.constants.MqConstants;
import cn.itcast.hotel.service.IHotelService;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
@Component
public class HotelListener {
@Autowired
private IHotelService hotelService;
//监听酒店新增和修改的业务
@RabbitListener(queues = MqConstants.HOTEL_INSERT_QUEUE)
public void listenHotelInsertOrUpdate(Long id){
hotelService.insertById(id);
}
//监听酒店删除的业务
@RabbitListener(queues = MqConstants.HOTEL_DELETE_QUEUE)
public void listenHotelDelete(Long id){
hotelService.deleteById(id);
}
}
hotel-demo的IHotelService.java
void deleteById(Long id); void insertById(Long id);
package cn.itcast.hotel.service;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import com.baomidou.mybatisplus.extension.service.IService;
import java.util.List;
import java.util.Map;
public interface IHotelService extends IService<Hotel> {
PageResult search(RequestParams params);
Map<String, List<String>> filters(RequestParams params);
List<String> getSuggestions(String prefix);
void deleteById(Long id);
void insertById(Long id);
}
hotel-demo的HotelService.java
@Override
public void deleteById(Long id) {
try {
//1、准备Request
DeleteRequest request = new DeleteRequest("hotel", id.toString());
//2、发送请求
client.delete(request,RequestOptions.DEFAULT);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public void insertById(Long id) {
try {
//0、根据id查询酒店数据
Hotel hotel = getById(id);
//转换成文档类型
HotelDoc hotelDoc = new HotelDoc(hotel);
//1、准备Request对象
IndexRequest request = new IndexRequest("hotel").id(hotel.getId().toString());
//2、准备json文档
request.source(JSON.toJSONString(hotelDoc), XContentType.JSON);
//3、发送请求
client.index(request,RequestOptions.DEFAULT);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
package cn.itcast.hotel.service.impl;
import cn.itcast.hotel.mapper.HotelMapper;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.apache.lucene.queries.function.FunctionScoreQuery;
import org.apache.lucene.search.vectorhighlight.ScoreOrderFragmentsBuilder;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.geo.GeoPoint;
import org.elasticsearch.common.unit.DistanceUnit;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.functionscore.FunctionScoreQueryBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortBuilders;
import org.elasticsearch.search.sort.SortOrder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Service
public class HotelService extends ServiceImpl<HotelMapper, Hotel> implements IHotelService {
@Autowired
private RestHighLevelClient client;
@Override
public PageResult search(RequestParams params) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
buildBasicQuery(params,request);
//2.2、分页
int page = params.getPage();
int size = params.getSize();
request.source().from((page - 1) * size).size(size);
//2.3、排序
String location = params.getLocation();
if(location != null && !"".equals(location)){
request.source().sort(SortBuilders
.geoDistanceSort("location",new GeoPoint(location))
.order(SortOrder.ASC)
.unit(DistanceUnit.KILOMETERS)
);
}
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
return handleResponse(response);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public Map<String, List<String>> filters(RequestParams params) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
//2.1、query
buildBasicQuery(params, request);
//2.2、设置size
request.source().size(0);
//2.3、聚合
buildAggregation(request);
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析响应
Map<String, List<String>> result = new HashMap<>();
Aggregations aggregations = response.getAggregations();
//4.1、根据品牌名称，获取品牌结果
List<String> brandList = getAggByName(aggregations,"brandAgg");
result.put("brand",brandList);
//4.1、根据城市名称，获取品牌结果
List<String> cityList = getAggByName(aggregations,"cityAgg");
result.put("city",cityList);
//4.1、根据星级名称，获取品牌结果
List<String> starList = getAggByName(aggregations,"starAgg");
result.put("starName",starList);
return result;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public List<String> getSuggestions(String prefix) {
try {
//1、准备Request
SearchRequest request = new SearchRequest("hotel");
//2、准备DSL
request.source().suggest(new SuggestBuilder().addSuggestion(
"suggestions",
SuggestBuilders.completionSuggestion("suggestion")
.prefix(prefix)
.skipDuplicates(true)
.size(10)
));
//3、发送请求
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4、解析结果
Suggest suggest = response.getSuggest();
//4.1、根据补全查询名称，获取补全结果
CompletionSuggestion suggestions = suggest.getSuggestion("suggestions");
//4.2、获取options
List<CompletionSuggestion.Entry.Option> options = suggestions.getOptions();
//4.3、遍历
List<String> list = new ArrayList<>(options.size());
for(CompletionSuggestion.Entry.Option option : options) {
String text = option.getText().toString();
list.add(text);
}
return list;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public void deleteById(Long id) {
try {
//1、准备Request
DeleteRequest request = new DeleteRequest("hotel", id.toString());
//2、发送请求
client.delete(request,RequestOptions.DEFAULT);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
@Override
public void insertById(Long id) {
try {
//0、根据id查询酒店数据
Hotel hotel = getById(id);
//转换成文档类型
HotelDoc hotelDoc = new HotelDoc(hotel);
//1、准备Request对象
IndexRequest request = new IndexRequest("hotel").id(hotel.getId().toString());
//2、准备json文档
request.source(JSON.toJSONString(hotelDoc), XContentType.JSON);
//3、发送请求
client.index(request,RequestOptions.DEFAULT);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
private List<String> getAggByName(Aggregations aggregations, String aggName) {
//4.1、根据聚合名称获聚合结果
Terms brandTerms = aggregations.get(aggName);
//4.2、获取buckets
List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
//4.3、遍历
List<String> brandList = new ArrayList<>();
for(Terms.Bucket bucket : buckets){
//4.4、获取key
String key = bucket.getKeyAsString();
brandList.add(key);
}
return brandList;
}
private void buildAggregation(SearchRequest request) {
request.source().aggregation(AggregationBuilders
.terms("brandAgg")
.field("brand")
.size(100)
);
request.source().aggregation(AggregationBuilders
.terms("cityAgg")
.field("city")
.size(100)
);
request.source().aggregation(AggregationBuilders
.terms("starAgg")
.field("starName")
.size(100)
);
}
private void buildBasicQuery(RequestParams params, SearchRequest request) {
//构建BooleanQuery
BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
//关键字搜索
String key = params.getKey();
if(key == null || "".equals(key)){
boolQuery.must(QueryBuilders.matchAllQuery());
}else{
boolQuery.must(QueryBuilders.matchQuery("all",key));
}
//城市条件
if(params.getCity() != null && !"".equals(params.getCity())){
boolQuery.filter(QueryBuilders.termQuery("city", params.getCity()));
}
//品牌条件
if(params.getBrand() != null && !"".equals(params.getBrand())){
boolQuery.filter(QueryBuilders.termQuery("brand", params.getBrand()));
}
//星级条件
if(params.getStarName() != null && !"".equals(params.getStarName())){
boolQuery.filter(QueryBuilders.termQuery("starName", params.getStarName()));
}
//价格
if(params.getMinPrice() != null && params.getMaxPrice() != null){
boolQuery.filter(QueryBuilders.rangeQuery("price").gte(params.getMinPrice()).lte(params.getMaxPrice()));
}
//算分控制
FunctionScoreQueryBuilder functionScoreQueryBuilder =
//构建Score
QueryBuilders.functionScoreQuery(
//原始查询，相关性算分
boolQuery,
//function score的数组
new FunctionScoreQueryBuilder.FilterFunctionBuilder[]{
//其中一个function score 元素
new FunctionScoreQueryBuilder.FilterFunctionBuilder(
//过滤条件
QueryBuilders.termQuery("isAD",true),
//算分函数
ScoreFunctionBuilders.weightFactorFunction(10)
)
});
request.source().query(functionScoreQueryBuilder);
}
private PageResult handleResponse(SearchResponse response) {
//4、解析响应
SearchHits searchHits = response.getHits();
//4.1获取总条数
long total = searchHits.getTotalHits().value;
//4.2文档数组
SearchHit[] hits = searchHits.getHits();
//4.3遍历
List<HotelDoc> hotels = new ArrayList<>();
for (SearchHit hit : hits) {
//获取文档source
String json = hit.getSourceAsString();
//反序列化
HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
//获取距离
Object[] sortValues = hit.getSortValues();
if(sortValues.length > 0){
Object sortValue = sortValues[0];
hotelDoc.setDistance(sortValue);
}
hotels.add(hotelDoc);
}
//4、封装返回
return new PageResult(total,hotels);
}
}
测试同步功能
运行hotel-demo和hotel-admin
在RabbitMQ中可以看到两个新的队列
?
交换机也有一个新的
?
在交换机里可以看到两个队列
?
在8099端口中，删除一个数据
?
在RabbitMQ可以看到一条消息?
?
并且在8089端口该数据确实找不到了
?
es集群
集群结果介绍
单机的elasticsearch做数据存储，必然面临两个问题:海量数据存储问题、单点故障问题。
1、海量数据存储问题：将索引库从逻辑上拆分为N个分片（shard），存储到多个节点
2、单点故障问题：将分片数据在不同节点备份（replica）
搭建集群
把该文件放到/root里
decker-composehttps://pan.baidu.com/s/1TJZz4GSoy6CA5DbC3IeL-w?pwd=a87u
运行指令
vi /etc/sysctl.conf?
在最后一行后面加上一条
vm.max_map_count=262144?
运行指令，若能看到刚刚输入的指令，则说明成功
sysctl -p?
运行指令，可以运行三个新的容器。注意一定要先关闭以前运行的es，否则会报错
docker-compose up -d?
解压该文件?
cerebrohttps://pan.baidu.com/s/1GlX4vsf1RQj1ocYufPDx5A?pwd=p0g9
运行lesson的cerebro-0.9.4的bin的cerebro.bat文件。若闪退，则编辑该文件。加上这两行。
注意D:\jdk\jdk8是你的jdk文件位置。闪退的原因是你的jdk等级过高，请下载jdk8并把这个位置写上你的jdk8的文件位置
?
访问localhost:9000。这里输入虚拟机ip加端口9200
?
可以看到集群中的节点信息。实心五角星是主节点，其他是候选节点
?
点击此处，创建索引库
?
name是索引库名字，number of shards是几个片，number of replicas是几个备份。最后点create创建
?
回到主页，可以看到每个片都有两个，因为每个片都有一个，而且我设置了一个备份，所以每个片有两个。实线框是主分片，虚线框是副本分片。
可以注意到，每个号码的主分片和副本分片一定不在同一个机器上。确保有机器宕机，不会造成数据故障。
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集群职责及脑裂
slasticsearch中集群节点有不同的职责划分，因此建议集群部署时，每个节点都有独立的角色
| 节点类型 | 配置参数 | 默认值 | 节点职责 |
| master eligible | node.master | true | 备选主节点:主节点可以管理和记录集群状态、决定分片在哪个节点、处理创建和删除索引库的请求 ? |
| data | node.data | true | 数据节点:存储数据、搜索、聚合、CRUD |
| ingest | node.ingest | true | 数据存储之前的预处理 |
| coordinating | 上面3个参数都为false 则为coordinating节点 | 无 | 路由请求到其它节点 合并其它节点处理的结果，返回给用户 |
默认情况下，每个节点都是master eligible节点，因此一旦master节点宕机，其它候选节点会选举一个成为主节点。当主节点与其他节点网络故障时，可能发生脑裂问题。
为了避免脑裂，需要要求选票超过( eligible节点数量+1 )/2才能当选为主，因此eligible节点数量最好是奇数。对应配置项是discovery.zen.minimum_master_nodes，在es7.0以后，已经成为默认配置，因此一般不会发生脑裂问题
ES集群的分布式存储
elasticsearch会通过hash算法来计算文档应该存储到哪个分片:
公式：
shard = hash(_routing)% number_of_shards
说明：
1、_routing默认是文档的id
2、算法与分片数量有关，因此索引库一旦创建，分片数量不能修改!
ES集群的分布式查询?
elasticsearch的查询分成两个阶段：
1、scatter phase：分散阶段，coordinating node会把请求分发到每一个分片
2、gather phase：聚集阶段，coordinating node汇总data node的搜索结果，并处理为最终结果集返回给用户
ES集群的故障转移
集群的master节点会监控集群中的节点状态，如果发现有节点宕机，会立即将宕机节点的分片数据迁移到其它节点，确保数据安全，这个叫做故障转移。?
当我停掉es01后，es01的分片分配给了其他的机器
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当我重启es后，es01的分片又回来了
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数据并未发生故障?
文章来源:https://blog.csdn.net/qq_63610563/article/details/135372501
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本文来自互联网用户投稿，该文观点仅代表作者本人，不代表本站立场。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。 如若内容造成侵权/违法违规/事实不符，请联系我的编程经验分享网邮箱：chenni525@qq.com进行投诉反馈，一经查实，立即删除！
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