Redis actual combat using Feed streaming to push blogs to fans

Redis pushes to fans in actual combat

two realization

   @Override
    public Result saveBlog(Blog blog) {
    
    
        // 1.获取登录用户
        UserDTO user = UserHolder.getUser();
        blog.setUserId(user.getId());
        // 2.保存探店笔记
        boolean isSuccess = save(blog);
        if(!isSuccess){
    
    
            return Result.fail("新增笔记失败!");
        }
        // 3.查询笔记作者的所有粉丝 select * from tb_follow where follow_user_id = ?
        List<Follow> follows = followService.query().eq("follow_user_id", user.getId()).list();
        // 4.推送笔记id给所有粉丝
        for (Follow follow : follows) {
    
    
            // 4.1.获取粉丝id
            Long userId = follow.getUserId();
            // 4.2.推送
            String key = FEED_KEY + userId;
            stringRedisTemplate.opsForZSet().add(key, blog.getId().toString(), System.currentTimeMillis());
        }
        // 5.返回id
        return Result.ok(blog.getId());
    }

  @Override
    public Result queryBlogOfFollow(Long max, Integer offset) {
    
    
        // 1.获取当前用户
        Long userId = UserHolder.getUser().getId();
        // 2.查询收件箱 ZREVRANGEBYSCORE key Max Min LIMIT offset count
        String key = FEED_KEY + userId;
        Set<ZSetOperations.TypedTuple<String>> typedTuples = stringRedisTemplate.opsForZSet()
                .reverseRangeByScoreWithScores(key, 0, max, offset, 2);
        // 3.非空判断
        if (typedTuples == null || typedTuples.isEmpty()) {
    
    
            return Result.ok();
        }
        // 4.解析数据：blogId、minTime（时间戳）、offset
        List<Long> ids = new ArrayList<>(typedTuples.size());
        long minTime = 0; //时间戳 2
        int os = 1; //重复个数 2
        for (ZSetOperations.TypedTuple<String> tuple : typedTuples) {
    
     // 5 4 4 2 2
            // 4.1.获取id
            ids.add(Long.valueOf(tuple.getValue()));
            // 4.2.获取分数(时间戳）
            long time = tuple.getScore().longValue();
            if(time == minTime){
    
    
                os++;
            }else{
    
    
                minTime = time;
                os = 1;
            }
        }

        // 5.根据id查询blog
        String idStr = StrUtil.join(",", ids);
        List<Blog> blogs = query().in("id", ids).last("ORDER BY FIELD(id," + idStr + ")").list();

        for (Blog blog : blogs) {
    
    
            // 5.1.查询blog有关的用户
            queryBlogUser(blog);
            // 5.2.查询blog是否被点赞
            isBlogLiked(blog);
        }

        // 6.封装并返回
        ScrollResult r = new ScrollResult();
        r.setList(blogs);
        r.setOffset(os);
        r.setMinTime(minTime);

        return Result.ok(r);
    }
@Data
public class ScrollResult {
    
    
    private List<?> list;
    private Long minTime;
    private Integer offset;
}