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今日内容

1 实时流式计算

1.1 应用场景

1.2 技术方案选型

2 Kafka Stream

2.1 概述

2.2 KafkaStream

2.3 入门demo

2.3.1 需求分析

2.3.2 实现

还是在kafka-demo的模块里实现

2.3.2.1 添加依赖

<dependency>
    <groupId>org.apache.kafka</groupId>
    <artifactId>kafka-streams</artifactId>
    <exclusions>
        <exclusion>
            <artifactId>connect-json</artifactId>
            <groupId>org.apache.kafka</groupId>
        </exclusion>
        <exclusion>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
        </exclusion>
    </exclusions>
</dependency>

2.3.2.2 创建快速启动，生成kafka流

public class KafkaStreamQuickStart {

    public static void main(String[] args) {

        //kafka的配置信息
        Properties prop = new Properties();
        prop.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG,"192.168.204.129:9092");
        prop.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());
        prop.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.String().getClass());
        prop.put(StreamsConfig.APPLICATION_ID_CONFIG,"streams-quickstart");

        //stream 构建器
        StreamsBuilder streamsBuilder = new StreamsBuilder();

        //流式计算
        streamProcessor(streamsBuilder);

        //创建kafkaStream对象
        KafkaStreams kafkaStreams = new KafkaStreams(streamsBuilder.build(),prop);
        //开启流式计算
        kafkaStreams.start();
    }

    /**
     * 流式计算
     * 消息的内容：hello kafka  hello itcast
     * @param streamsBuilder
     */
    private static void streamProcessor(StreamsBuilder streamsBuilder) {
        //创建kstream对象，同时指定从那个topic中接收消息
        KStream<String, String> stream = streamsBuilder.stream("itcast-topic-input");
        /**
         * 处理消息的value
         */
        stream.flatMapValues(new ValueMapper<String, Iterable<String>>() {
                    @Override
                    public Iterable<String> apply(String value) {
                        return Arrays.asList(value.split(" "));
                    }
                })
                //按照value进行聚合处理
                .groupBy((key,value)->value)
                //时间窗口
                .windowedBy(TimeWindows.of(Duration.ofSeconds(10)))
                //统计单词的个数
                .count()
                //转换为kStream
                .toStream()
                .map((key,value)->{
                    System.out.println("key:"+key+",vlaue:"+value);
                    return new KeyValue<>(key.key().toString(),value.toString());
                })
                //发送消息
                .to("itcast-topic-out");
    }
}

2.3.2.3 修改生产者

修改com.heima.kafka.sample.ProducerQuickStart的方法

public class ProducerQuickStart {
 
    public static void main(String[] args) throws ExecutionException, InterruptedException {
        //1.kafka的配置信息
        Properties properties = new Properties();
        //kafka的连接地址
        properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,"192.168.204.129:9092");
        //发送失败，失败的重试次数
        properties.put(ProducerConfig.RETRIES_CONFIG,5);
        //消息key的序列化器
        properties.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");
        //消息value的序列化器
        properties.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");
 
        //2.生产者对象
        KafkaProducer<String,String> producer = new KafkaProducer<String, String>(properties);

        /**
         * 第一个参数：topic 第二个参数：key 第三个参数：value
         */
        //封装发送的消息
        //ProducerRecord<String,String> record = new ProducerRecord<String, String>("topic-first","key-001","hello kafka");
        for(int i=0;i<5;i++){
            ProducerRecord<String,String> record = new ProducerRecord<String, String>("itcast-topic-input","hello kafka"+" "+i);
            //3.发送消息
            producer.send(record);
        }
        producer.close();

2.3.2.4 修改消费者

修改com.heima.kafka.sample.ConsumerQuickStart的方法

public class ConsumerQuickStart {
 
    public static void main(String[] args) {
        //1.添加kafka的配置信息
        Properties properties = new Properties();
        //kafka的连接地址
        properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "192.168.204.129:9092");
        //消费者组
        properties.put(ConsumerConfig.GROUP_ID_CONFIG, "group1");
        //消息的反序列化器
        properties.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
        properties.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
        //手动提交偏移量
        //properties.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, "false");

        //2.消费者对象
        KafkaConsumer<String, String> consumer = new KafkaConsumer<String, String>(properties);
 
        //3.订阅主题
        consumer.subscribe(Collections.singletonList("itcast-topic-out"));

 
        //当前线程一直处于监听状态
        while (true) {
            //4.获取消息
            ConsumerRecords<String, String> consumerRecords = consumer.poll(Duration.ofMillis(1000));
            for (ConsumerRecord<String, String> consumerRecord : consumerRecords) {
                System.out.println(consumerRecord.key());
                System.out.println(consumerRecord.value());
                System.out.println(consumerRecord.offset());
                System.out.println(consumerRecord.partition());
            }
        }
 
    }
 
}

2.3.2.5 测试

先启动消费者，再启动kafkaStream，再启动生产者

发送消息为"hello kafka"+" "+i，一共五次

符合我们发的

2.4 SpringBoot集合KafkaStream

2.4.1 创建自定配置参数类

在kafka-demo中创建com.heima.kafka.config.KafkaStreamConfig类

/**
 * 通过重新注册KafkaStreamsConfiguration对象，设置自定配置参数
 */
@Getter
@Setter
@Configuration
@EnableKafkaStreams
@ConfigurationProperties(prefix="kafka")
public class KafkaStreamConfig {
    private static final int MAX_MESSAGE_SIZE = 16* 1024 * 1024;
    private String hosts;
    private String group;
    @Bean(name = KafkaStreamsDefaultConfiguration.DEFAULT_STREAMS_CONFIG_BEAN_NAME)
    public KafkaStreamsConfiguration defaultKafkaStreamsConfig() {
        Map<String, Object> props = new HashMap<>();
        props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, hosts);//连接信息
        props.put(StreamsConfig.APPLICATION_ID_CONFIG, this.getGroup()+"_stream_aid");//组
        props.put(StreamsConfig.CLIENT_ID_CONFIG, this.getGroup()+"_stream_cid");//应用名称
        props.put(StreamsConfig.RETRIES_CONFIG, 10);//重试次数
        props.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());//key序列化器
        props.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.String().getClass());
        return new KafkaStreamsConfiguration(props);
    }
}

2.4.2 修改配置文件

修改heima-leadnews-test/kafka-demo/src/main/resources/application.yaml

将其放到最底下

kafka:
  hosts: 192.168.204.129:9092
  group: ${spring.application.name}

server:
  port: 9991
spring:
  application:
    name: kafka-demo
  kafka:
    bootstrap-servers: 192.168.204.129:9092
    producer:
      retries: 10
      key-serializer: org.apache.kafka.common.serialization.StringSerializer
      value-serializer: org.apache.kafka.common.serialization.StringSerializer
    consumer:
      group-id: ${spring.application.name}-test
      key-deserializer: org.apache.kafka.common.serialization.StringDeserializer
      value-deserializer: org.apache.kafka.common.serialization.StringDeserializer
kafka:
  hosts: 192.168.204.129:9092
  group: ${spring.application.name}

2.4.3 创建配置类创建KStream对象

创建com.heima.kafka.stream.KafkaStreamHelloListener

等于KStream放入spring容器中进行直接监听

@Configuration
@Slf4j
public class KafkaStreamHelloListener {
    @Bean
    public KStream<String,String> kStream(StreamsBuilder streamsBuilder){
        //创建kstream对象，同时指定从那个topic中接收消息
        KStream<String, String> stream = streamsBuilder.stream("itcast-topic-input");
        stream.flatMapValues(new ValueMapper<String, Iterable<String>>() {
            @Override
            public Iterable<String> apply(String value) {
                return Arrays.asList(value.split(" "));
            }
        })
                //根据value进行聚合分组
                .groupBy((key,value)->value)
                //聚合计算时间间隔
                .windowedBy(TimeWindows.of(Duration.ofSeconds(10)))
                //求单词的个数
                .count()
                .toStream()
                //处理后的结果转换为string字符串
                .map((key,value)->{
                    System.out.println("key:"+key+",value:"+value);
                    return new KeyValue<>(key.key().toString(),value.toString());
                })
                //发送消息
                .to("itcast-topic-out");
        return stream;
    }
}

2.4.4 测试

启动kafka启动类，启动消费者和生产者

发送消息是"hello kafka"，一共五次

3 热点文章实时计算

3.1 思路说明

3.2 实现步骤

3.3 具体实现

3.3.1 为行为微服务添加kafka配置

在heima-leadnews-behavior微服务中集成kafka生产者配置

spring:
  application:
    name: leadnews-behavior
  kafka:
    bootstrap-servers: 192.168.204.129:9092
    producer:
      retries: 10
      key-serializer: org.apache.kafka.common.serialization.StringSerializer
      value-serializer: org.apache.kafka.common.serialization.StringSerializer

3.3.2 行为微服务中发送消息的消息体实体类

定义消息发送封装类：UpdateArticleMess

在heima-leadnews-model中创建com.heima.model.message.UpdateArticleMess实体类

package com.heima.model.message;
 
import lombok.Data;
 
@Data
public class UpdateArticleMess {
 
    /**
     * 修改文章的字段类型
      */
    private UpdateArticleType type;
    /**
     * 文章ID
     */
    private Long articleId;
    /**
     * 修改数据的增量，可为正负
     */
    private Integer add;
 
    public enum UpdateArticleType{
        COLLECTION,COMMENT,LIKES,VIEWS;
    }
}

3.3.3 定义kafka流接收的topic

在heima-leadnews-common中创建com.heima.common.constants.HotArticleConstants常量类

package com.heima.common.constants;
public class HotArticleConstants {
    public static final String HOT_ARTICLE_SCORE_TOPIC="hot.article.score.topic";
}

3.3.4 修改用户行为后的逻辑（相当于生产者）

点赞之后就要发送消息了，所以去修改用户点赞的实现类com.heima.behavior.service.impl.ApLikesBehaviorServiceImpl

@Service
@Transactional
@Slf4j
public class ApLikesBehaviorServiceImpl implements ApLikesBehaviorService {

    @Autowired
    private CacheService cacheService;
    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;

    @Override
    public ResponseResult like(LikesBehaviorDto dto) {

        //1.检查参数
        if (dto == null || dto.getArticleId() == null || checkParam(dto)) {
            return ResponseResult.errorResult(AppHttpCodeEnum.PARAM_INVALID);
        }

        //2.是否登录
        ApUser user = AppThreadLocalUtil.getUser();
        if (user == null) {
            return ResponseResult.errorResult(AppHttpCodeEnum.NEED_LOGIN);
        }

        //组装发送给kafka的消息类
        UpdateArticleMess message =new UpdateArticleMess();
        message.setArticleId(dto.getArticleId());
        message.setType(UpdateArticleMess.UpdateArticleType.LIKES);

        //3.点赞  保存数据
        if (dto.getOperation() == 0) {
            Object obj = cacheService.hGet(BehaviorConstants.LIKE_BEHAVIOR + dto.getArticleId().toString(), user.getId().toString());
            if (obj != null) {
                return ResponseResult.errorResult(AppHttpCodeEnum.PARAM_INVALID, "已点赞");
            }
            // 保存当前key
            log.info("保存当前key:{} ,{}, {}", dto.getArticleId(), user.getId(), dto);
            cacheService.hPut(BehaviorConstants.LIKE_BEHAVIOR + dto.getArticleId().toString(), user.getId().toString(), JSON.toJSONString(dto));
            //添加行为的正负
            message.setAdd(1);
        } else {
            // 删除当前key
            log.info("删除当前key:{}, {}", dto.getArticleId(), user.getId());
            cacheService.hDelete(BehaviorConstants.LIKE_BEHAVIOR + dto.getArticleId().toString(), user.getId().toString());
            //添加行为的正负
            message.setAdd(-1);
        }

        //4.给kafka发送消息
        kafkaTemplate.send(HotArticleConstants.HOT_ARTICLE_SCORE_TOPIC, JSON.toJSONString(message));
        
        return ResponseResult.okResult(AppHttpCodeEnum.SUCCESS);

    }

    /**
     * 检查参数
     *
     * @return
     */
    private boolean checkParam(LikesBehaviorDto dto) {
        if (dto.getType() > 2 || dto.getType() < 0 || dto.getOperation() > 1 || dto.getOperation() < 0) {
            return true;
        }
        return false;
    }
}

点赞有，阅读都有，一样需要改

@Service
@Transactional
@Slf4j
public class ApReadBehaviorServiceImpl implements ApReadBehaviorService {

    @Autowired
    private CacheService cacheService;
    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;

    @Override
    public ResponseResult readBehavior(ReadBehaviorDto dto) {
        //1.检查参数
        if (dto == null || dto.getArticleId() == null) {
            return ResponseResult.errorResult(AppHttpCodeEnum.PARAM_INVALID);
        }

        //2.是否登录
        ApUser user = AppThreadLocalUtil.getUser();
        if (user == null) {
            return ResponseResult.errorResult(AppHttpCodeEnum.NEED_LOGIN);
        }
        //组装发送给kafka的消息类
        UpdateArticleMess message =new UpdateArticleMess();
        message.setArticleId(dto.getArticleId());
        message.setType(UpdateArticleMess.UpdateArticleType.VIEWS);

        //更新阅读次数
        String readBehaviorJson = (String) cacheService.hGet(BehaviorConstants.READ_BEHAVIOR + dto.getArticleId().toString(), user.getId().toString());
        if (StringUtils.isNotBlank(readBehaviorJson)) {
            ReadBehaviorDto readBehaviorDto = JSON.parseObject(readBehaviorJson, ReadBehaviorDto.class);
            dto.setCount((short) (readBehaviorDto.getCount() + dto.getCount()));
        }
        // 保存当前key
        log.info("保存当前key:{} {} {}", dto.getArticleId(), user.getId(), dto);
        cacheService.hPut(BehaviorConstants.READ_BEHAVIOR + dto.getArticleId().toString(), user.getId().toString(), JSON.toJSONString(dto));
        //添加行为的正负
        message.setAdd(1);
        //发送消息
        kafkaTemplate.send(HotArticleConstants.HOT_ARTICLE_SCORE_TOPIC, JSON.toJSONString(message));
        return ResponseResult.okResult(AppHttpCodeEnum.SUCCESS);

    }
}

3.3.5 Stream聚合

因为用户行为最后都体现在文章上面，所以kafkaStream的数据聚合应该在文章微服务中。

3.3.5.1 创建自定配置参数类

在heima-leadnews-article中创建com.heima.article.config.KafkaStreamConfig配置类

@Getter
@Setter
@Configuration
@EnableKafkaStreams
@ConfigurationProperties(prefix="kafka")
public class KafkaStreamConfig {
    private static final int MAX_MESSAGE_SIZE = 16* 1024 * 1024;
    private String hosts;
    private String group;
    @Bean(name = KafkaStreamsDefaultConfiguration.DEFAULT_STREAMS_CONFIG_BEAN_NAME)
    public KafkaStreamsConfiguration defaultKafkaStreamsConfig() {
        Map<String, Object> props = new HashMap<>();
        props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, hosts);//连接信息
        props.put(StreamsConfig.APPLICATION_ID_CONFIG, this.getGroup()+"_stream_aid");//组
        props.put(StreamsConfig.CLIENT_ID_CONFIG, this.getGroup()+"_stream_cid");//应用名称
        props.put(StreamsConfig.RETRIES_CONFIG, 10);//重试次数
        props.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());//key序列化器
        props.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.String().getClass());
        return new KafkaStreamsConfiguration(props);
    }
}

3.3.5.2 添加kafkaStream的配置

在nacos中为文章微服务添加kafkaStream的配置

kafka:
  hosts: 192.168.204.129:9092
  group: ${spring.application.name}

3.3.5.3 定义kafka流转发的topic

在com.heima.common.constants.HotArticleConstants中添加HOT_ARTICLE_INCR_HANDLE_TOPIC

public class HotArticleConstants {
    public static final String HOT_ARTICLE_SCORE_TOPIC="hot.article.score.topic";
    public static final String HOT_ARTICLE_INCR_HANDLE_TOPIC="hot.article.incr.handle.topic";
}

3.3.5.4 文章微服务中的发送消息的消息体实体类

因为聚合后的数据是COLLECTION:0,COMMENT:0,LIKES:0,VIEWS:0，不包含文章id，所以需要一个类把他们封装起来

在heima-leadnews-model中创建com.heima.model.message.ArticleVisitStreamMess实体类

@Data
public class ArticleVisitStreamMess {
    /**
     * 文章id
     */
    private Long articleId;
    /**
     * 阅读
     */
    private int view;
    /**
     * 收藏
     */
    private int collect;
    /**
     * 评论
     */
    private int comment;
    /**
     * 点赞
     */
    private int like;
}

3.3.5.5 创建配置类创建KStream对象

定义stream,接收消息并聚合，创建com.heima.article.stream.HotArticleStreamHandler类

@Configuration
@Slf4j
public class HotArticleStreamHandler {

    @Bean
    public KStream<String,String> kStream(StreamsBuilder streamsBuilder){
        //接收消息
        KStream<String,String> stream = streamsBuilder.stream(HotArticleConstants.HOT_ARTICLE_SCORE_TOPIC);
        //聚合流式处理
        stream.map((key,value)->{
                    UpdateArticleMess mess = JSON.parseObject(value, UpdateArticleMess.class);
                    //重置消息的key:1234343434   和  value: likes:1
                    return new KeyValue<>(mess.getArticleId().toString(),mess.getType().name()+":"+mess.getAdd());
                })
                //按照文章id进行聚合
                .groupBy((key,value)->key)
                //时间窗口
                .windowedBy(TimeWindows.of(Duration.ofSeconds(10)))
                /**
                 * 自行的完成聚合的计算
                 */
                .aggregate(new Initializer<String>() {
                    /**
                     * 初始方法，返回值是消息的value 初始值，也就是aggValue
                     * @return
                     */
                    @Override
                    public String apply() {
                        return "COLLECTION:0,COMMENT:0,LIKES:0,VIEWS:0";
                    }
                    /**
                     * 真正的聚合操作，返回值是消息的value
                     */
                }, new Aggregator<String, String, String>() {
                    /**
                     * key:文章id value:消息的value  aggValue:初始值
                     * @param key key:1234343434
                     * @param value value: likes:1
                     * @param aggValue 初始值 COLLECTION:0,COMMENT:0,LIKES:0,VIEWS:0
                     * @return
                     */
                    @Override
                    public String apply(String key, String value, String aggValue) {
                        if(StringUtils.isBlank(value)){
                            return aggValue;
                        }
                        String[] aggAry = aggValue.split(",");
                        int col = 0,com=0,lik=0,vie=0;
                        for (String agg : aggAry) {
                            String[] split = agg.split(":");
                            /**
                             * 获得初始值，也是时间窗口内计算之后的值
                             */
                            switch (UpdateArticleMess.UpdateArticleType.valueOf(split[0])){
                                case COLLECTION:
                                    col = Integer.parseInt(split[1]);
                                    break;
                                case COMMENT:
                                    com = Integer.parseInt(split[1]);
                                    break;
                                case LIKES:
                                    lik = Integer.parseInt(split[1]);
                                    break;
                                case VIEWS:
                                    vie = Integer.parseInt(split[1]);
                                    break;
                            }
                        }
                        /**
                         * 累加操作
                         */
                        String[] valAry = value.split(":");
                        switch (UpdateArticleMess.UpdateArticleType.valueOf(valAry[0])){
                            case COLLECTION:
                                col += Integer.parseInt(valAry[1]);
                                break;
                            case COMMENT:
                                com += Integer.parseInt(valAry[1]);
                                break;
                            case LIKES:
                                lik += Integer.parseInt(valAry[1]);
                                break;
                            case VIEWS:
                                vie += Integer.parseInt(valAry[1]);
                                break;
                        }

                        String formatStr = String.format("COLLECTION:%d,COMMENT:%d,LIKES:%d,VIEWS:%d", col, com, lik, vie);
                        System.out.println("文章的id:"+key);
                        System.out.println("当前时间窗口内的消息处理结果："+formatStr);
                        return formatStr;
                    }
                }, Materialized.as("hot-atricle-stream-count-001"))
                .toStream()
                /**
                 * 格式化消息的key和value
                 */
                .map((key,value)->{
                    return new KeyValue<>(key.key().toString(),formatObj(key.key().toString(),value));
                })
                //发送消息
                .to(HotArticleConstants.HOT_ARTICLE_INCR_HANDLE_TOPIC);

        return stream;
    }

    /**
     * 格式化消息的value数据
     * @param articleId
     * @param value
     * @return
     */
    public String formatObj(String articleId,String value){
        ArticleVisitStreamMess mess = new ArticleVisitStreamMess();
        mess.setArticleId(Long.valueOf(articleId));
        //COLLECTION:0,COMMENT:0,LIKES:0,VIEWS:0
        String[] valAry = value.split(",");
        for (String val : valAry) {
            String[] split = val.split(":");
            switch (UpdateArticleMess.UpdateArticleType.valueOf(split[0])){
                case COLLECTION:
                    mess.setCollect(Integer.parseInt(split[1]));
                    break;
                case COMMENT:
                    mess.setComment(Integer.parseInt(split[1]));
                    break;
                case LIKES:
                    mess.setLike(Integer.parseInt(split[1]));
                    break;
                case VIEWS:
                    mess.setView(Integer.parseInt(split[1]));
                    break;
            }
        }
        log.info("聚合消息处理之后的结果为:{}",JSON.toJSONString(mess));
        return JSON.toJSONString(mess);
    }
}

3.3.6 创建消费者，用于监听聚合后的消息

创建com.heima.article.listener.ArticleIncrHandleListener用于监听和处理聚合后的消息

@Component
@Slf4j
public class ArticleIncrHandleListener {
 
    @Autowired
    private ApArticleService apArticleService;
 
    @KafkaListener(topics = HotArticleConstants.HOT_ARTICLE_INCR_HANDLE_TOPIC)
    public void onMessage(String mess){
        if(StringUtils.isNotBlank(mess)){
            ArticleVisitStreamMess articleVisitStreamMess = JSON.parseObject(mess, ArticleVisitStreamMess.class);
            apArticleService.updateScore(articleVisitStreamMess);
        }
    }
}

3.3.7 在文章微服务中更新当前分值

3.3.8 Service添加updateScore方法

在文章微服务的service中完善功能

接口

void updateScore(ArticleVisitStreamMess articleVisitStreamMess);

实现：

/**
 * 更新文章的分值  同时更新缓存中的热点文章数据
 * @param mess
 */
@Override
public void updateScore(ArticleVisitStreamMess mess) {
    //1.更新文章的阅读、点赞、收藏、评论的数量
    ApArticle apArticle = updateArticle(mess);
    //2.计算文章的分值
    Integer score = computeScore(apArticle);
    score = score * 3;

    //3.替换当前文章对应频道的热点数据
    replaceDataToRedis(apArticle, score, ArticleConstants.HOT_ARTICLE_FIRST_PAGE + apArticle.getChannelId());

    //4.替换推荐对应的热点数据
    replaceDataToRedis(apArticle, score, ArticleConstants.HOT_ARTICLE_FIRST_PAGE + ArticleConstants.DEFAULT_TAG);
}

/**
 * 替换数据并且存入到redis
 * @param apArticle
 * @param score
 * @param s
 */
private void replaceDataToRedis(ApArticle apArticle, Integer score, String s) {
    String articleListStr = cacheService.get(s);
    if (StringUtils.isNotBlank(articleListStr)) {
        List<HotArticleVo> hotArticleVoList = JSON.parseArray(articleListStr, HotArticleVo.class);

        boolean flag = true;

        //如果缓存中存在该文章，只更新分值
        for (HotArticleVo hotArticleVo : hotArticleVoList) {
            if (hotArticleVo.getId().equals(apArticle.getId())) {
                hotArticleVo.setScore(score);
                flag = false;
                break;
            }
        }

        //如果缓存中不存在，查询缓存中分值最小的一条数据，进行分值的比较，如果当前文章的分值大于缓存中的数据，就替换
        if (flag) {
            if (hotArticleVoList.size() >= 30) {
                hotArticleVoList = hotArticleVoList.stream().sorted(Comparator.comparing(HotArticleVo::getScore).reversed()).collect(Collectors.toList());
                HotArticleVo lastHot = hotArticleVoList.get(hotArticleVoList.size() - 1);
                if (lastHot.getScore() < score) {
                    hotArticleVoList.remove(lastHot);
                    HotArticleVo hot = new HotArticleVo();
                    BeanUtils.copyProperties(apArticle, hot);
                    hot.setScore(score);
                    hotArticleVoList.add(hot);
                }

            } else {
                HotArticleVo hot = new HotArticleVo();
                BeanUtils.copyProperties(apArticle, hot);
                hot.setScore(score);
                hotArticleVoList.add(hot);
            }
        }
        //缓存到redis
        hotArticleVoList = hotArticleVoList.stream().sorted(Comparator.comparing(HotArticleVo::getScore).reversed()).collect(Collectors.toList());
        cacheService.set(s, JSON.toJSONString(hotArticleVoList));
    }
}

/**
 * 更新文章行为数量
 * @param mess
 */
private ApArticle updateArticle(ArticleVisitStreamMess mess) {
    ApArticle apArticle = getById(mess.getArticleId());
    apArticle.setCollection(apArticle.getCollection()==null?0:apArticle.getCollection()+mess.getCollect());
    apArticle.setComment(apArticle.getComment()==null?0:apArticle.getComment()+mess.getComment());
    apArticle.setLikes(apArticle.getLikes()==null?0:apArticle.getLikes()+mess.getLike());
    apArticle.setViews(apArticle.getViews()==null?0:apArticle.getViews()+mess.getView());
    updateById(apArticle);
    return apArticle;
}

/**
 * 计算文章的具体分值
 * @param apArticle
 * @return
 */
private Integer computeScore(ApArticle apArticle) {
    Integer score = 0;
    if(apArticle.getLikes() != null){
        score += apArticle.getLikes() * ArticleConstants.HOT_ARTICLE_LIKE_WEIGHT;
    }
    if(apArticle.getViews() != null){
        score += apArticle.getViews()* ArticleConstants.HOT_ARTICLE_VIEW_WEIGHT;
    }
    if(apArticle.getComment() != null){
        score += apArticle.getComment() * ArticleConstants.HOT_ARTICLE_COMMENT_WEIGHT;
    }
    if(apArticle.getCollection() != null){
        score += apArticle.getCollection() * ArticleConstants.HOT_ARTICLE_COLLECTION_WEIGHT;
    }
    return score;
}

3.4 测试

前端有问题，就不测试了，功能能明白就行。