9.2 修改记录信息测试
同时，我们可以再测试修改，我们将用户头像路径进行修改，看看 es 是否同步了新的数据：
UPDATE `user` SET icon='https:///langlang' WHERE id=1001
查看 es 信息，使用 apipost 发送请求：【GET】http://192.168.65.133:9200/es_demo_collect/_search
// 以下是该请求需要携带的json数据，表示查询es_demo_collect索引中的全部文档数据 { "query": { "match_all": {} } }
10.实战开发-后端代码
以下只展示我认为比较与本文相关的比较重要的文件，完整源码的获取链接我会放在文章的最后。
10.1 pom.xml依赖
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.fox</groupId> <artifactId>elasticsearch-canal-demo</artifactId> <version>1.0-SNAPSHOT</version> <properties> <maven.compiler.source>8</maven.compiler.source> <maven.compiler.target>8</maven.compiler.target> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <version>2.6.3</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.18.24</version> </dependency> <dependency> <groupId>org.elasticsearch.client</groupId> <artifactId>elasticsearch-rest-high-level-client</artifactId> <version>7.8.0</version> </dependency> <!--fastjson依赖--> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.33</version> </dependency> <dependency> <groupId>cn.hutool</groupId> <artifactId>hutool-all</artifactId> <version>5.8.7</version> </dependency> </dependencies> </project>
10.2 application.yml配置
server: # 服务端口 port: 9999 elasticsearch: # es访问ip hostname: 192.168.65.133 # es访问port port: 9200 blog: # 访问索引 index: es_demo_collect # 搜索返回字段 source_fields: userId,title,username,userIcon,introduce,createTime,updateTime
10.3 ElasticsearchConfig.java配置类
package com.fox.es.config; import org.apache.http.HttpHost; import org.elasticsearch.client.RestClient; import org.elasticsearch.client.RestClientBuilder; import org.elasticsearch.client.RestHighLevelClient; import org.springframework.beans.factory.annotation.Value; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; /** * @author 狐狸半面添 * @create 2023-03-22 17:51 */ @Configuration public class ElasticsearchConfig { @Value("${elasticsearch.hostname}") private String hostname; @Value("${elasticsearch.port}") private Integer port; @Bean public RestHighLevelClient restHighLevelClient() { RestClientBuilder builder = RestClient.builder( new HttpHost(hostname, port, "http") ); return new RestHighLevelClient(builder); } }
10.4 ⭐测试是否连接 es 成功
package com.fox.es.controller; import com.fox.es.entity.Result; import org.elasticsearch.client.RequestOptions; import org.elasticsearch.client.RestHighLevelClient; import org.elasticsearch.client.core.MainResponse; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController; import javax.annotation.Resource; import java.io.IOException; /** * @author 狐狸半面添 * @create 2023-03-22 18:33 */ @RestController public class TestController { @Resource private RestHighLevelClient restHighLevelClient; /** * 用于测试是否连接 es 成功 * * @return 返回 es 的基本信息，等价于访问：http://127.0.0.1:9200 * @throws IOException 异常信息 */ @GetMapping("/getEsInfo") public Result getEsInfo() throws IOException { MainResponse info = restHighLevelClient.info(RequestOptions.DEFAULT); return Result.ok(info); } }
浏览器访问：http://localhost:9999/getEsInfo
10.5 ⭐搜索服务
10.5.1 controller层
package com.fox.es_canal.controller; import com.fox.es_canal.constant.BlogConstants; import com.fox.es_canal.entity.Result; import com.fox.es_canal.service.BlogService; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.RestController; import javax.annotation.Resource; /** * @author 狐狸半面添 * @create 2023-03-22 20:16 */ @RestController @RequestMapping("/blog") public class BlogController { @Resource private BlogService blogService; /** * 通过关键词获取数据列表 * * @param keyWords 关键词 * @param pageNo 页码 * @return 数据列表，按照相关性从高到低进行排序 */ @GetMapping("/list") public Result list(@RequestParam("keyWords") String keyWords, @RequestParam("pageNo") Integer pageNo) { // BlogConstants是我写的一个常量类，里面定义了一个变量 SEARCH_PAGE_NUM = 15 return blogService.list(keyWords, pageNo, BlogConstants.SEARCH_PAGE_NUM); } }
10.5.2 service接口层
package com.fox.es_canal.service; import com.fox.es_canal.entity.Result; /** * @author 狐狸半面添 * @create 2023-03-22 20:18 */ public interface BlogService { /** * 通过关键词获取数据列表 * * @param keyWords 关键词 * @param pageNo 页码 * @param pageSize 每页大小 * @return 数据列表，按照相关性从高到低进行排序 */ Result list(String keyWords, int pageNo, int pageSize); }
10.5.3 service实现层
package com.fox.es_canal.service.impl; import com.alibaba.fastjson.JSON; import com.alibaba.fastjson.JSONObject; import com.fox.es_canal.dto.BlogSimpleInfoDTO; import com.fox.es_canal.entity.Result; import com.fox.es_canal.service.BlogService; import lombok.extern.slf4j.Slf4j; 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.text.Text; import org.elasticsearch.index.query.BoolQueryBuilder; import org.elasticsearch.index.query.MultiMatchQueryBuilder; import org.elasticsearch.index.query.QueryBuilders; import org.elasticsearch.search.SearchHit; import org.elasticsearch.search.SearchHits; import org.elasticsearch.search.builder.SearchSourceBuilder; import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder; import org.elasticsearch.search.fetch.subphase.highlight.HighlightField; import org.springframework.beans.factory.annotation.Value; import org.springframework.stereotype.Service; import org.springframework.util.StringUtils; import javax.annotation.Resource; import java.io.IOException; import java.time.LocalDateTime; import java.time.format.DateTimeFormatter; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; /** * @author 狐狸半面添 * @create 2023-03-22 20:18 */ @Slf4j @Service public class BlogServiceImpl implements BlogService { @Resource private RestHighLevelClient restHighLevelClient; @Value("${elasticsearch.blog.index}") private String blogIndexStore; @Value("${elasticsearch.blog.source_fields}") private String blogFields; public Result list(String keyWords, int pageNo, int pageSize) { // 1.设置索引 - blog SearchRequest searchRequest = new SearchRequest(blogIndexStore); SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder(); BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery(); // 2.source源字段过虑 String[] sourceFieldsArray = blogFields.split(","); searchSourceBuilder.fetchSource(sourceFieldsArray, new String[]{}); // 3.关键字 if (StringUtils.hasText(keyWords)) { // 哪些字段匹配关键字 MultiMatchQueryBuilder multiMatchQueryBuilder = QueryBuilders.multiMatchQuery(keyWords, "title", "tags", "username", "introduce", "content"); // 设置匹配占比（表示最少匹配的子句个数,例如有五个可选子句,最少的匹配个数为5*70%=3.5.向下取整为3,这就表示五个子句最少要匹配其中三个才能查到） multiMatchQueryBuilder.minimumShouldMatch("70%"); // 提升字段的Boost值 multiMatchQueryBuilder.field("title", 15); multiMatchQueryBuilder.field("tags", 10); multiMatchQueryBuilder.field("introduce", 7); multiMatchQueryBuilder.field("content", 3); multiMatchQueryBuilder.field("username", 3); boolQueryBuilder.must(multiMatchQueryBuilder); } // 4.分页 int start = (pageNo - 1) * pageSize; searchSourceBuilder.from(start); searchSourceBuilder.size(pageSize); // 布尔查询 searchSourceBuilder.query(boolQueryBuilder); // 6.高亮设置 HighlightBuilder highlightBuilder = new HighlightBuilder(); highlightBuilder.preTags("<font color='red'>"); highlightBuilder.postTags("</font>"); // 设置高亮字段 ArrayList<HighlightBuilder.Field> fields = new ArrayList<>(); fields.add(new HighlightBuilder.Field("title")); fields.add(new HighlightBuilder.Field("introduce")); fields.add(new HighlightBuilder.Field("username")); highlightBuilder.fields().addAll(fields); searchSourceBuilder.highlighter(highlightBuilder); // 请求搜索 searchRequest.source(searchSourceBuilder); SearchResponse searchResponse; try { searchResponse = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT); } catch (IOException e) { log.error("博客搜索异常：{}", e.getMessage()); return Result.error(e.getMessage()); } // 结果集处理 SearchHits hits = searchResponse.getHits(); SearchHit[] searchHits = hits.getHits(); // 记录总数 long totalHitsCount = hits.getTotalHits().value; // 数据列表 List<BlogSimpleInfoDTO> list = new ArrayList<>(); for (SearchHit hit : searchHits) { JSONObject jsonObject = JSONObject.parseObject(hit.getSourceAsString()); BlogSimpleInfoDTO blog = new BlogSimpleInfoDTO(); blog.setId(Integer.parseInt(hit.getId())); blog.setUsername(jsonObject.getString("username")); blog.setTitle(jsonObject.getString("title")); blog.setUserId(Long.parseLong(jsonObject.getString("userId"))); blog.setUserIcon(jsonObject.getString("userIcon")); blog.setIntroduce(jsonObject.getString("introduce")); blog.setCreateTime(LocalDateTime.parse(jsonObject.getString("createTime"), DateTimeFormatter.ISO_OFFSET_DATE_TIME)); blog.setUpdateTime(LocalDateTime.parse(jsonObject.getString("updateTime"), DateTimeFormatter.ISO_OFFSET_DATE_TIME)); // 取出高亮字段内容 Map<String, HighlightField> highlightFields = hit.getHighlightFields(); if (highlightFields != null) { blog.setTitle(parseHighlightStr(blog.getTitle(), highlightFields.get("title"))); blog.setIntroduce(parseHighlightStr(blog.getIntroduce(), highlightFields.get("introduce"))); blog.setUsername(parseHighlightStr(blog.getUsername(), highlightFields.get("username"))); } list.add(blog); } // 封装信息返回前端 HashMap<String, Object> resultMap = new HashMap<>(4); // 页码 resultMap.put("pageNo", pageNo); // 每页记录数量 resultMap.put("pageSize", pageSize); // 总记录数 resultMap.put("total", totalHitsCount); // 该页信息 resultMap.put("items", list); return Result.ok(resultMap); } public String parseHighlightStr(String text, HighlightField field) { if (field != null) { Text[] fragments = field.getFragments(); StringBuilder stringBuilder = new StringBuilder(); for (Text str : fragments) { stringBuilder.append(str.string()); } return stringBuilder.toString(); } else { return text; } } }
10.5.4 效果测试
这里我们使用 apipost7 或浏览器 进行测试：
11.源码获取
Java源码地址：Mr-Write/SpringbootDemo: 各种demo案例 (github.com)
对应的是 elasticsearch-canal-demo 包模块。
12.其它说明
当我们在Java中写出往MySQL数据库添加、删除、修改博客记录的操作接口时，会同时通过 Canal 同步到es中，因为 canal 同步的本质还是去读 MySQL的 binlog 日志。由于比较简单，在这里就不做演示了。
