Spring Cloud+Redis是如何實(shí)現(xiàn)點(diǎn)贊、取消點(diǎn)贊的?
點(diǎn)贊功能在很多系統(tǒng)中都有,但別看功能小,想要做好需要考慮的東西還挺多的。
點(diǎn)贊、取消點(diǎn)贊是高頻次的操作,若每次都讀寫數(shù)據(jù)庫(kù),大量的操作會(huì)影響數(shù)據(jù)庫(kù)性能,所以需要做緩存。
至于多久從 Redis 取一次數(shù)據(jù)存到數(shù)據(jù)庫(kù)中,根據(jù)項(xiàng)目的實(shí)際情況定吧,我是暫時(shí)設(shè)了兩個(gè)小時(shí)。
項(xiàng)目需求需要查看都誰(shuí)點(diǎn)贊了,所以要存儲(chǔ)每個(gè)點(diǎn)贊的點(diǎn)贊人、被點(diǎn)贊人,不能簡(jiǎn)單的做計(jì)數(shù)。
文章分四部分介紹:
- Redis 緩存設(shè)計(jì)及實(shí)現(xiàn)
- 數(shù)據(jù)庫(kù)設(shè)計(jì)
- 數(shù)據(jù)庫(kù)操作
- 開啟定時(shí)任務(wù)持久化存儲(chǔ)到數(shù)據(jù)庫(kù)
一、Redis 緩存設(shè)計(jì)及實(shí)現(xiàn)
1.1 Redis 安裝及運(yùn)行
Redis 安裝請(qǐng)自行查閱相關(guān)教程。
說(shuō)下Docker 安裝運(yùn)行 Redis
- docker run -d -p 6379:6379 redis:4.0.8
如果已經(jīng)安裝了 Redis,打開命令行,輸入啟動(dòng) Redis 的命令
- redis-server
1.2 Redis 與 SpringBoot 項(xiàng)目的整合
1.在 pom.xml 中引入依賴
- <dependency>
- <groupId>org.springframework.boot</groupId>
- <artifactId>spring-boot-starter-data-redis</artifactId>
- </dependency>
2.在啟動(dòng)類上添加注釋 @EnableCaching
- @SpringBootApplication
- @EnableDiscoveryClient
- @EnableSwagger2
- @EnableFeignClients(basePackages = "com.solo.coderiver.project.client")
- @EnableCaching
- publicclass UserApplication {
- public static void main(String[] args) {
- SpringApplication.run(UserApplication.class, args);
- }
- }
3.編寫 Redis 配置類 RedisConfig
- import com.fasterxml.jackson.annotation.JsonAutoDetect;
- import com.fasterxml.jackson.annotation.PropertyAccessor;
- import com.fasterxml.jackson.databind.ObjectMapper;
- import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
- import org.springframework.context.annotation.Bean;
- import org.springframework.context.annotation.Configuration;
- import org.springframework.data.redis.connection.RedisConnectionFactory;
- import org.springframework.data.redis.core.RedisTemplate;
- import org.springframework.data.redis.core.StringRedisTemplate;
- import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
- import java.net.UnknownHostException;
- @Configuration
- publicclass RedisConfig {
- @Bean
- @ConditionalOnMissingBean(name = "redisTemplate")
- public RedisTemplate<String, Object> redisTemplate(
- RedisConnectionFactory redisConnectionFactory)
- throws UnknownHostException {
- Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<Object>(Object.class);
- ObjectMapper om = new ObjectMapper();
- om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
- om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
- jackson2JsonRedisSerializer.setObjectMapper(om);
- RedisTemplate<String, Object> template = new RedisTemplate<String, Object>();
- template.setConnectionFactory(redisConnectionFactory);
- template.setKeySerializer(jackson2JsonRedisSerializer);
- template.setValueSerializer(jackson2JsonRedisSerializer);
- template.setHashKeySerializer(jackson2JsonRedisSerializer);
- template.setHashValueSerializer(jackson2JsonRedisSerializer);
- template.afterPropertiesSet();
- return template;
- }
- @Bean
- @ConditionalOnMissingBean(StringRedisTemplate.class)
- public StringRedisTemplate stringRedisTemplate(
- RedisConnectionFactory redisConnectionFactory)
- throws UnknownHostException {
- StringRedisTemplate template = new StringRedisTemplate();
- template.setConnectionFactory(redisConnectionFactory);
- return template;
- }
- }
至此 Redis 在 SpringBoot 項(xiàng)目中的配置已經(jīng)完成,可以愉快的使用了。
1.3 Redis 的數(shù)據(jù)結(jié)構(gòu)類型
Redis 可以存儲(chǔ)鍵與5種不同數(shù)據(jù)結(jié)構(gòu)類型之間的映射,這5種數(shù)據(jù)結(jié)構(gòu)類型分別為String(字符串)、List(列表)、Set(集合)、Hash(散列)和 Zset(有序集合)。
下面來(lái)對(duì)這5種數(shù)據(jù)結(jié)構(gòu)類型作簡(jiǎn)單的介紹:
1.4 點(diǎn)贊數(shù)據(jù)在 Redis 中的存儲(chǔ)格式
用 Redis 存儲(chǔ)兩種數(shù)據(jù),一種是記錄點(diǎn)贊人、被點(diǎn)贊人、點(diǎn)贊狀態(tài)的數(shù)據(jù),另一種是每個(gè)用戶被點(diǎn)贊了多少次,做個(gè)簡(jiǎn)單的計(jì)數(shù)。
由于需要記錄點(diǎn)贊人和被點(diǎn)贊人,還有點(diǎn)贊狀態(tài)(點(diǎn)贊、取消點(diǎn)贊),還要固定時(shí)間間隔取出 Redis 中所有點(diǎn)贊數(shù)據(jù),分析了下 Redis 數(shù)據(jù)格式中 Hash 最合適。
因?yàn)?Hash 里的數(shù)據(jù)都是存在一個(gè)鍵里,可以通過(guò)這個(gè)鍵很方便的把所有的點(diǎn)贊數(shù)據(jù)都取出。這個(gè)鍵里面的數(shù)據(jù)還可以存成鍵值對(duì)的形式,方便存入點(diǎn)贊人、被點(diǎn)贊人和點(diǎn)贊狀態(tài)。
設(shè)點(diǎn)贊人的 id 為 likedPostId,被點(diǎn)贊人的 id 為 likedUserId ,點(diǎn)贊時(shí)狀態(tài)為 1,取消點(diǎn)贊狀態(tài)為 0。將點(diǎn)贊人 id 和被點(diǎn)贊人 id 作為鍵,兩個(gè) id 中間用 :: 隔開,點(diǎn)贊狀態(tài)作為值。
所以如果用戶點(diǎn)贊,存儲(chǔ)的鍵為:likedUserId::likedPostId,對(duì)應(yīng)的值為 1 。取消點(diǎn)贊,存儲(chǔ)的鍵為:likedUserId::likedPostId,對(duì)應(yīng)的值為 0 。取數(shù)據(jù)時(shí)把鍵用 :: 切開就得到了兩個(gè)id,也很方便。
在可視化工具 RDM 中看到的是這樣子
1.5 操作 Redis
將具體操作方法封裝到了 RedisService 接口里
RedisService.java
- import com.solo.coderiver.user.dataobject.UserLike;
- import com.solo.coderiver.user.dto.LikedCountDTO;
- import java.util.List;
- publicinterface RedisService {
- /**
- * 點(diǎn)贊。狀態(tài)為1
- * @param likedUserId
- * @param likedPostId
- */
- void saveLiked2Redis(String likedUserId, String likedPostId);
- /**
- * 取消點(diǎn)贊。將狀態(tài)改變?yōu)?
- * @param likedUserId
- * @param likedPostId
- */
- void unlikeFromRedis(String likedUserId, String likedPostId);
- /**
- * 從Redis中刪除一條點(diǎn)贊數(shù)據(jù)
- * @param likedUserId
- * @param likedPostId
- */
- void deleteLikedFromRedis(String likedUserId, String likedPostId);
- /**
- * 該用戶的點(diǎn)贊數(shù)加1
- * @param likedUserId
- */
- void incrementLikedCount(String likedUserId);
- /**
- * 該用戶的點(diǎn)贊數(shù)減1
- * @param likedUserId
- */
- void decrementLikedCount(String likedUserId);
- /**
- * 獲取Redis中存儲(chǔ)的所有點(diǎn)贊數(shù)據(jù)
- * @return
- */
- List<UserLike> getLikedDataFromRedis();
- /**
- * 獲取Redis中存儲(chǔ)的所有點(diǎn)贊數(shù)量
- * @return
- */
- List<LikedCountDTO> getLikedCountFromRedis();
- }
實(shí)現(xiàn)類 RedisServiceImpl.java
- import com.solo.coderiver.user.dataobject.UserLike;
- import com.solo.coderiver.user.dto.LikedCountDTO;
- import com.solo.coderiver.user.enums.LikedStatusEnum;
- import com.solo.coderiver.user.service.LikedService;
- import com.solo.coderiver.user.service.RedisService;
- import com.solo.coderiver.user.utils.RedisKeyUtils;
- import lombok.extern.slf4j.Slf4j;
- import org.springframework.beans.factory.annotation.Autowired;
- import org.springframework.data.redis.core.Cursor;
- import org.springframework.data.redis.core.RedisTemplate;
- import org.springframework.data.redis.core.ScanOptions;
- import org.springframework.stereotype.Service;
- import java.util.ArrayList;
- import java.util.List;
- import java.util.Map;
- @Service
- @Slf4j
- publicclass RedisServiceImpl implements RedisService {
- @Autowired
- RedisTemplate redisTemplate;
- @Autowired
- LikedService likedService;
- @Override
- public void saveLiked2Redis(String likedUserId, String likedPostId) {
- String key = RedisKeyUtils.getLikedKey(likedUserId, likedPostId);
- redisTemplate.opsForHash().put(RedisKeyUtils.MAP_KEY_USER_LIKED, key, LikedStatusEnum.LIKE.getCode());
- }
- @Override
- public void unlikeFromRedis(String likedUserId, String likedPostId) {
- String key = RedisKeyUtils.getLikedKey(likedUserId, likedPostId);
- redisTemplate.opsForHash().put(RedisKeyUtils.MAP_KEY_USER_LIKED, key, LikedStatusEnum.UNLIKE.getCode());
- }
- @Override
- public void deleteLikedFromRedis(String likedUserId, String likedPostId) {
- String key = RedisKeyUtils.getLikedKey(likedUserId, likedPostId);
- redisTemplate.opsForHash().delete(RedisKeyUtils.MAP_KEY_USER_LIKED, key);
- }
- @Override
- public void incrementLikedCount(String likedUserId) {
- redisTemplate.opsForHash().increment(RedisKeyUtils.MAP_KEY_USER_LIKED_COUNT, likedUserId, 1);
- }
- @Override
- public void decrementLikedCount(String likedUserId) {
- redisTemplate.opsForHash().increment(RedisKeyUtils.MAP_KEY_USER_LIKED_COUNT, likedUserId, -1);
- }
- @Override
- public List<UserLike> getLikedDataFromRedis() {
- Cursor<Map.Entry<Object, Object>> cursor = redisTemplate.opsForHash().scan(RedisKeyUtils.MAP_KEY_USER_LIKED, ScanOptions.NONE);
- List<UserLike> list = new ArrayList<>();
- while (cursor.hasNext()){
- Map.Entry<Object, Object> entry = cursor.next();
- String key = (String) entry.getKey();
- //分離出 likedUserId,likedPostId
- String[] split = key.split("::");
- String likedUserId = split[0];
- String likedPostId = split[1];
- Integer value = (Integer) entry.getValue();
- //組裝成 UserLike 對(duì)象
- UserLike userLike = new UserLike(likedUserId, likedPostId, value);
- list.add(userLike);
- //存到 list 后從 Redis 中刪除
- redisTemplate.opsForHash().delete(RedisKeyUtils.MAP_KEY_USER_LIKED, key);
- }
- return list;
- }
- @Override
- public List<LikedCountDTO> getLikedCountFromRedis() {
- Cursor<Map.Entry<Object, Object>> cursor = redisTemplate.opsForHash().scan(RedisKeyUtils.MAP_KEY_USER_LIKED_COUNT, ScanOptions.NONE);
- List<LikedCountDTO> list = new ArrayList<>();
- while (cursor.hasNext()){
- Map.Entry<Object, Object> map = cursor.next();
- //將點(diǎn)贊數(shù)量存儲(chǔ)在 LikedCountDT
- String key = (String)map.getKey();
- LikedCountDTO dto = new LikedCountDTO(key, (Integer) map.getValue());
- list.add(dto);
- //從Redis中刪除這條記錄
- redisTemplate.opsForHash().delete(RedisKeyUtils.MAP_KEY_USER_LIKED_COUNT, key);
- }
- return list;
- }
- }
用到的工具類和枚舉類
RedisKeyUtils, 用于根據(jù)一定規(guī)則生成 key
- publicclass RedisKeyUtils {
- //保存用戶點(diǎn)贊數(shù)據(jù)的key
- publicstaticfinal String MAP_KEY_USER_LIKED = "MAP_USER_LIKED";
- //保存用戶被點(diǎn)贊數(shù)量的key
- publicstaticfinal String MAP_KEY_USER_LIKED_COUNT = "MAP_USER_LIKED_COUNT";
- /**
- * 拼接被點(diǎn)贊的用戶id和點(diǎn)贊的人的id作為key。格式 222222::333333
- * @param likedUserId 被點(diǎn)贊的人id
- * @param likedPostId 點(diǎn)贊的人的id
- * @return
- */
- public static String getLikedKey(String likedUserId, String likedPostId){
- StringBuilder builder = new StringBuilder();
- builder.append(likedUserId);
- builder.append("::");
- builder.append(likedPostId);
- return builder.toString();
- }
- }
LikedStatusEnum 用戶點(diǎn)贊狀態(tài)的枚舉類
- package com.solo.coderiver.user.enums;
- import lombok.Getter;
- /**
- * 用戶點(diǎn)贊的狀態(tài)
- */
- @Getter
- publicenum LikedStatusEnum {
- LIKE(1, "點(diǎn)贊"),
- UNLIKE(0, "取消點(diǎn)贊/未點(diǎn)贊"),
- ;
- private Integer code;
- private String msg;
- LikedStatusEnum(Integer code, String msg) {
- this.code = code;
- this.msg = msg;
- }
- }
二、數(shù)據(jù)庫(kù)設(shè)計(jì)
數(shù)據(jù)庫(kù)表中至少要包含三個(gè)字段:被點(diǎn)贊用戶id,點(diǎn)贊用戶id,點(diǎn)贊狀態(tài)。再加上主鍵id,創(chuàng)建時(shí)間,修改時(shí)間就行了。
建表語(yǔ)句
- create table `user_like`(
- `id` int not null auto_increment,
- `liked_user_id` varchar(32) not null comment '被點(diǎn)贊的用戶id',
- `liked_post_id` varchar(32) not null comment '點(diǎn)贊的用戶id',
- `status` tinyint(1) default'1' comment '點(diǎn)贊狀態(tài),0取消,1點(diǎn)贊',
- `create_time` timestamp not nulldefault current_timestamp comment '創(chuàng)建時(shí)間',
- `update_time` timestamp not nulldefault current_timestamp on update current_timestamp comment '修改時(shí)間',
- primary key(`id`),
- INDEX `liked_user_id`(`liked_user_id`),
- INDEX `liked_post_id`(`liked_post_id`)
- ) comment '用戶點(diǎn)贊表';
對(duì)應(yīng)的對(duì)象 UserLike
- import com.solo.coderiver.user.enums.LikedStatusEnum;
- import lombok.Data;
- import javax.persistence.Entity;
- import javax.persistence.GeneratedValue;
- import javax.persistence.GenerationType;
- import javax.persistence.Id;
- /**
- * 用戶點(diǎn)贊表
- */
- @Entity
- @Data
- publicclass UserLike {
- //主鍵id
- @Id
- @GeneratedValue(strategy = GenerationType.IDENTITY)
- private Integer id;
- //被點(diǎn)贊的用戶的id
- private String likedUserId;
- //點(diǎn)贊的用戶的id
- private String likedPostId;
- //點(diǎn)贊的狀態(tài).默認(rèn)未點(diǎn)贊
- private Integer status = LikedStatusEnum.UNLIKE.getCode();
- public UserLike() {
- }
- public UserLike(String likedUserId, String likedPostId, Integer status) {
- this.likedUserId = likedUserId;
- this.likedPostId = likedPostId;
- this.status = status;
- }
- }
三、數(shù)據(jù)庫(kù)操作
操作數(shù)據(jù)庫(kù)同樣封裝在接口中
LikedService
- import com.solo.coderiver.user.dataobject.UserLike;
- import org.springframework.data.domain.Page;
- import org.springframework.data.domain.Pageable;
- import java.util.List;
- publicinterface LikedService {
- /**
- * 保存點(diǎn)贊記錄
- * @param userLike
- * @return
- */
- UserLike save(UserLike userLike);
- /**
- * 批量保存或修改
- * @param list
- */
- List<UserLike> saveAll(List<UserLike> list);
- /**
- * 根據(jù)被點(diǎn)贊人的id查詢點(diǎn)贊列表(即查詢都誰(shuí)給這個(gè)人點(diǎn)贊過(guò))
- * @param likedUserId 被點(diǎn)贊人的id
- * @param pageable
- * @return
- */
- Page<UserLike> getLikedListByLikedUserId(String likedUserId, Pageable pageable);
- /**
- * 根據(jù)點(diǎn)贊人的id查詢點(diǎn)贊列表(即查詢這個(gè)人都給誰(shuí)點(diǎn)贊過(guò))
- * @param likedPostId
- * @param pageable
- * @return
- */
- Page<UserLike> getLikedListByLikedPostId(String likedPostId, Pageable pageable);
- /**
- * 通過(guò)被點(diǎn)贊人和點(diǎn)贊人id查詢是否存在點(diǎn)贊記錄
- * @param likedUserId
- * @param likedPostId
- * @return
- */
- UserLike getByLikedUserIdAndLikedPostId(String likedUserId, String likedPostId);
- /**
- * 將Redis里的點(diǎn)贊數(shù)據(jù)存入數(shù)據(jù)庫(kù)中
- */
- void transLikedFromRedis2DB();
- /**
- * 將Redis中的點(diǎn)贊數(shù)量數(shù)據(jù)存入數(shù)據(jù)庫(kù)
- */
- void transLikedCountFromRedis2DB();
- }
LikedServiceImpl 實(shí)現(xiàn)類
- import com.solo.coderiver.user.dataobject.UserInfo;
- import com.solo.coderiver.user.dataobject.UserLike;
- import com.solo.coderiver.user.dto.LikedCountDTO;
- import com.solo.coderiver.user.enums.LikedStatusEnum;
- import com.solo.coderiver.user.repository.UserLikeRepository;
- import com.solo.coderiver.user.service.LikedService;
- import com.solo.coderiver.user.service.RedisService;
- import com.solo.coderiver.user.service.UserService;
- import lombok.extern.slf4j.Slf4j;
- import org.springframework.beans.factory.annotation.Autowired;
- import org.springframework.data.domain.Page;
- import org.springframework.data.domain.Pageable;
- import org.springframework.stereotype.Service;
- import org.springframework.transaction.annotation.Transactional;
- import java.util.List;
- @Service
- @Slf4j
- publicclass LikedServiceImpl implements LikedService {
- @Autowired
- UserLikeRepository likeRepository;
- @Autowired
- RedisService redisService;
- @Autowired
- UserService userService;
- @Override
- @Transactional
- public UserLike save(UserLike userLike) {
- return likeRepository.save(userLike);
- }
- @Override
- @Transactional
- public List<UserLike> saveAll(List<UserLike> list) {
- return likeRepository.saveAll(list);
- }
- @Override
- public Page<UserLike> getLikedListByLikedUserId(String likedUserId, Pageable pageable) {
- return likeRepository.findByLikedUserIdAndStatus(likedUserId, LikedStatusEnum.LIKE.getCode(), pageable);
- }
- @Override
- public Page<UserLike> getLikedListByLikedPostId(String likedPostId, Pageable pageable) {
- return likeRepository.findByLikedPostIdAndStatus(likedPostId, LikedStatusEnum.LIKE.getCode(), pageable);
- }
- @Override
- public UserLike getByLikedUserIdAndLikedPostId(String likedUserId, String likedPostId) {
- return likeRepository.findByLikedUserIdAndLikedPostId(likedUserId, likedPostId);
- }
- @Override
- @Transactional
- public void transLikedFromRedis2DB() {
- List<UserLike> list = redisService.getLikedDataFromRedis();
- for (UserLike like : list) {
- UserLike ul = getByLikedUserIdAndLikedPostId(like.getLikedUserId(), like.getLikedPostId());
- if (ul == null){
- //沒(méi)有記錄,直接存入
- save(like);
- }else{
- //有記錄,需要更新
- ul.setStatus(like.getStatus());
- save(ul);
- }
- }
- }
- @Override
- @Transactional
- public void transLikedCountFromRedis2DB() {
- List<LikedCountDTO> list = redisService.getLikedCountFromRedis();
- for (LikedCountDTO dto : list) {
- UserInfo user = userService.findById(dto.getId());
- //點(diǎn)贊數(shù)量屬于無(wú)關(guān)緊要的操作,出錯(cuò)無(wú)需拋異常
- if (user != null){
- Integer likeNum = user.getLikeNum() + dto.getCount();
- user.setLikeNum(likeNum);
- //更新點(diǎn)贊數(shù)量
- userService.updateInfo(user);
- }
- }
- }
- }
數(shù)據(jù)庫(kù)的操作就這些,主要還是增刪改查。
四、開啟定時(shí)任務(wù)持久化存儲(chǔ)到數(shù)據(jù)庫(kù)
定時(shí)任務(wù) Quartz 很強(qiáng)大,就用它了。
Quartz 使用步驟:
1.添加依賴
- <dependency>
- <groupId>org.springframework.boot</groupId>
- <artifactId>spring-boot-starter-quartz</artifactId>
- </dependency>
2.編寫配置文件
- package com.solo.coderiver.user.config;
- import com.solo.coderiver.user.task.LikeTask;
- import org.quartz.*;
- import org.springframework.context.annotation.Bean;
- import org.springframework.context.annotation.Configuration;
- @Configuration
- publicclass QuartzConfig {
- privatestaticfinal String LIKE_TASK_IDENTITY = "LikeTaskQuartz";
- @Bean
- public JobDetail quartzDetail(){
- return JobBuilder.newJob(LikeTask.class).withIdentity(LIKE_TASK_IDENTITY).storeDurably().build();
- }
- @Bean
- public Trigger quartzTrigger(){
- SimpleScheduleBuilder scheduleBuilder = SimpleScheduleBuilder.simpleSchedule()
- // .withIntervalInSeconds(10) //設(shè)置時(shí)間周期單位秒
- .withIntervalInHours(2) //兩個(gè)小時(shí)執(zhí)行一次
- .repeatForever();
- return TriggerBuilder.newTrigger().forJob(quartzDetail())
- .withIdentity(LIKE_TASK_IDENTITY)
- .withSchedule(scheduleBuilder)
- .build();
- }
- }
3.編寫執(zhí)行任務(wù)的類繼承自 QuartzJobBean
- package com.solo.coderiver.user.task;
- import com.solo.coderiver.user.service.LikedService;
- import lombok.extern.slf4j.Slf4j;
- import org.apache.commons.lang.time.DateUtils;
- import org.quartz.JobExecutionContext;
- import org.quartz.JobExecutionException;
- import org.springframework.beans.factory.annotation.Autowired;
- import org.springframework.scheduling.quartz.QuartzJobBean;
- import java.text.SimpleDateFormat;
- import java.util.Date;
- /**
- * 點(diǎn)贊的定時(shí)任務(wù)
- */
- @Slf4j
- publicclass LikeTask extends QuartzJobBean {
- @Autowired
- LikedService likedService;
- private SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
- @Override
- protected void executeInternal(JobExecutionContext jobExecutionContext) throws JobExecutionException {
- log.info("LikeTask-------- {}", sdf.format(new Date()));
- //將 Redis 里的點(diǎn)贊信息同步到數(shù)據(jù)庫(kù)里
- likedService.transLikedFromRedis2DB();
- likedService.transLikedCountFromRedis2DB();
- }
- }
在定時(shí)任務(wù)中直接調(diào)用 LikedService 封裝的方法完成數(shù)據(jù)同步。
以上就是點(diǎn)贊功能的設(shè)計(jì)與實(shí)現(xiàn),不足之處還請(qǐng)各位大佬多多指教。
另外,點(diǎn)贊/取消點(diǎn)贊 跟 點(diǎn)贊數(shù) +1/ -1 應(yīng)該保證是原子操作 , 不然出現(xiàn)并發(fā)問(wèn)題就會(huì)有兩條重復(fù)的點(diǎn)贊記錄 , 所以要給整個(gè)原子操作加鎖 . 同時(shí)需要在Spring Boot 的系統(tǒng)關(guān)閉鉤子函數(shù)中補(bǔ)充同步redis中點(diǎn)贊數(shù)據(jù)到mysql中的過(guò)程 . 不然有可能出現(xiàn)距離上一次同步1小時(shí)59分的時(shí)候服務(wù)器更新 , 把整整兩小時(shí)的點(diǎn)贊數(shù)據(jù)都給清空了 . 如果點(diǎn)贊設(shè)計(jì)到比較重要活動(dòng)業(yè)務(wù)的話這就很尷尬了 。