PHP+redis实现微博的拉模型案例详解

user:username:userid:$userid

//1、保存微博
$conn = connredis();
$postid = $conn->incr('global:postid');
$conn->hmset('post:postid:'.$postid,['userid'=>$user['userid'],'username'=>$user['username'],'time'=>time(),'content'=>$content]);
//2、每个人维护20条最新微博，保存到有序集合中
$conn->zadd('starpost:userid:'.$user['userid'],$postid,$postid);
if($conn->zcard('starpost:userid:'.$user['userid']) > 20){
  $conn->zremrangebyrank('starpost:userid:'.$user['userid'],0,0);
}
//3、维护个人的1000条微博，保存到链表中
$conn->lpush('mypost:userid:'.$user['userid'],$postid);
if($conn->llen('mypost:userid:'.$user['userid']) > 1000){
  $conn->rpoplpush('mypost:userid:'.$user['userid'],'global:post');
}

//1、获取拉取对象
$stars = $conn->smembers('following:'.$user['userid']);//获取所有关注的人
$stars[] = $user['userid'];//需要拉取自己的微博
//2、获取上次拉取的位置
$lastpull = $conn->get('lastpull:userid:'.$user['userid']);
if(!$lastpull){
$lastpull = 0;
}
//3、拉取微博 
$latest = [];
foreach($stars as $star){
$latest = array_merge($latest,$conn->zrangebyscore('starpost:userid:'.$star,$lastpull+1,1<<32-1));
}
//4、给微博排序
sort($latest,SORT_NUMERIC);
//5、设置拉取的位置
if(!empty($latest)){
  $conn->set('lastpull:userid:'.$user['userid'],end($latest));
}
//6、写入到已拉取表中
foreach($latest as $l){
  $conn->lpush('receivepost:'.$user['userid'],$l);
}
$conn->ltrim('receivepost:'.$user['userid'],0,999);//至多显示1000条微博
//7、获取微博的详细内容
$postids = $conn->sort('receivepost:'.$user['userid'],['sort'=>'desc']);
$posts = [];
foreach($postids as $postid){
  $posts[] = $conn->hmget('post:postid:'.$postid,['userid','username','time','content']);
}
//8、获取粉丝和关注数
$fansnum = $conn->scard('follower:'.$user['userid']);
$follownum = $conn->scard('following:'.$user['userid']);