Redis in Action 文章投票

环境：LNMP（CentOS 6.6 + Nginx 1.8.0 + MySQL 5.6.23 + PHP 5.6.9）+ Redis 3.0.7 + phpredis 2.2.4

[root@localhost ~]# cd /usr/local/redis/
[root@localhost redis]# ./bin/redis-server ./etc/redis.conf 
[root@localhost redis]# ps aux|grep redis

root      2239  0.2  0.1  35556  1744 ?        Ssl  12:08   0:00 ./bin/redis-server *:6379          
root      2243  0.0  0.0   5976   724 pts/0    S+   12:08   0:00 grep redis

<?php

// 一周的秒数
$seconds = 7 * 86400;
define(ONE_WEEK_IN_SECONDS, $seconds);
// 每投一票文章加的分值
define(VOTE_SCORE, 432);

// 实例化Redis对象
$redis = new Redis();
// 连接到Redis服务器
$conn = $redis->connect('localhost', 6379);

<?php

/* 为投票网站准备数据 */

require 'redis.php';

//1.根据发布时间排序文章的有序集合 zset
$article_info = [
	'100408'=>[
			'time'=>strtotime('2016-4-10'),
			'score'=>1332164063.49
	],
	'100635'=>[
			'time'=>strtotime('2016-4-28'),
			'score'=>1332174713.47
	],
	'100716'=>[
			'time'=>strtotime('2016-4-29'),
			'score'=>1332225027.26
	]
];

foreach($article_info as $key => $val) {
	$redis->zadd('time:', $val['time'], 'article:'.$key);
}

//2.根据评分排序文章的有序集合 zset
foreach($article_info as $key => $val) {
	$redis->zadd('score:', $val['score'], 'article:'.$key);
}

//3.为某篇文章(id:100408)投过票的用户集合 set
$users = [234487, 253378, 364680, 132097, 350917];
foreach($users as $key => $val) {
	$redis->sadd('voted:100408', $val);
}

<?php

header('Content-type:text/html;charset=utf-8');

require 'redis.php';

$user_id = empty($_GET['user_id']) ? 0 : (int)$_GET['user_id'];
$article_id = empty($_GET['article_id']) ? 0 : (int)$_GET['article_id'];

function article_vote($redis, $user_id, $article_id) {
	$cutoff = time() - ONE_WEEK_IN_SECONDS;
	// 127.0.0.1:6379> zscore time article:100408
	// "1460217600"
	if(intval($redis->zscore('time:', 'article:'.$article_id)) < $cutoff) {
		return false;
	}

	if($redis->sadd('voted:'.$article_id, $user_id)) {
		// ZINCRBY key increment member
		// 为有序集 score 的成员 article:100408 的 score 值加上增量 increment
		$score_new = $redis->zincrby('score:', VOTE_SCORE, 'article:'.$article_id);
		echo $score_new;
		// HINCRBY key field increment
		// 为哈希表key中的域field的值加上增量increment。
		// 如果用户是第一次为这篇文章投票，那么增加这篇文章的投票数量和评分

	} else {
		return false;
	}	
	return true;
}

if(! article_vote($redis, $user_id, $article_id)) {
	echo '投票失败';
} else {
	echo '投票成功';
}

[root@localhost redis]# ./bin/redis-cli
127.0.0.1:6379> zrange score: 0 -1 withscores
1) "article:100408"
2) "1332164063.49"
3) "article:100635"
4) "1332174713.47"
5) "article:100716"
6) "1332225027.26"
127.0.0.1:6379> zrange time: 0 -1 withscores
1) "article:100408"
2) "1460217600"
3) "article:100635"
4) "1461772800"
5) "article:100716"
6) "1461859200"

127.0.0.1:6379> zrange score: 0 -1 withscores
1) "article:100408"
2) "1332164495.49"
3) "article:100635"
4) "1332174713.47"
5) "article:100716"
6) "1332225027.26"
127.0.0.1:6379> smembers voted:100408
1) "100"
2) "132097"
3) "234487"
4) "253378"
5) "350917"
6) "364680"
127.0.0.1:6379> 

<?php

require 'redis.php';

// @param object $redis redis对象
// @param int $user_id  用户编号
// @param string $title 文章标题
// @param string $link  文章链接
function post_article($redis, $user_id, $title, $link) {
	$article_id = $redis->incr('article:'); // 生成新的文章id

	$voted = 'voted:'.$article_id;
	$redis->sadd($voted, $user_id); // 将发布文章的用户添加到文章已投票的用户名单中
	$redis->expire($voted, ONE_WEEK_IN_SECONDS); // 将投票名单的过期时间设置为一周

	$now = time();
	$article = 'article:'.$article_id;
	$redis->hmset($article, [
		'title' => $title,
		'link' => $link,
		'poster' => $user_id,
		'time' => $now,
		'votes'=> 1
	]); // 将文章的信息存储到一个散列里

	$redis->zadd('score:', $now + VOTE_SCORE, $article); // 把文章添加到根据评分排序的有序集合中
	$redis->zadd('time:', $now, $article); // 把文章添加到根据发布时间排序的有序集合中

	return $article_id;
}

$user_id = isset($_GET['user_id']) ? $_GET['user_id'] : 0;
$mtid = mt_rand(0,999);
$title = '文章标题'.$mtid;
$link = 'http://www.youdomain.com/article/'.$mtid;
if(post_article($redis, $user_id, $title, $link)) {
	echo 'success';
} else {
	echo 'error';
}

127.0.0.1:6379> zrange time: 0 -1 withscores
1) "article:100408"
2) "1460217600"
3) "article:100635"
4) "1461772800"
5) "article:100716"
6) "1461859200"
7) "article:1"
8) "1465105632"
127.0.0.1:6379> zrange score: 0 -1 withscores
1) "article:100408"
2) "1332164495.49"
3) "article:100635"
4) "1332174713.47"
5) "article:100716"
6) "1332225027.26"
7) "article:1"
8) "1465106064"
127.0.0.1:6379> smembers voted:1
1) "0"
127.0.0.1:6379> hgetall article:1
 1) "title"
 2) "\xe6\x96\x87\xe7\xab\xa0\xe6\xa0\x87\xe9\xa2\x9868"
 3) "link"
 4) "http://www.youdomain.com/article/68"
 5) "poster"
 6) "0"
 7) "time"
 8) "1465105632"
 9) "votes"
10) "1"

<?php

require 'redis.php';

define(ARTICLES_PER_PAGE, 5); // 每页5条数据

// @param object $redis redis对象
// @param int $page 当前页
// @param string $order 根据$order来排序 
// @return array $articles 文章信息
function get_articles($redis, $page, $order = 'score:') {
	$start = ($page - 1) * ARTICLES_PER_PAGE;
	$end = $start + ARTICLES_PER_PAGE - 1;

	$ids = $redis->zrevrange($order, $start, $end); // 获取多个文件的序号 按 score 值递减(从大到小)来排列。
	$articles = [];
	foreach($ids as $id) {
		$article_data = $redis->hgetall($id);	
		$article_data['id'] = $id;
		$articles[] = $article_data;
	}

	return $articles;
}

$page = isset($_GET['page']) ? $_GET['page'] : 1;
$articles = get_articles($redis, $page);

echo '<pre>';
print_r($articles);

Array
(
    [0] => Array
        (
            [title] => 文章标题23
            [link] => http://www.youdomain.com/article/23
            [poster] => 106
            [time] => 1465180517
            [votes] => 1
            [id] => article:8
        )

    [1] => Array
        (
            [title] => 文章标题719
            [link] => http://www.youdomain.com/article/719
            [poster] => 105
            [time] => 1465180514
            [votes] => 1
            [id] => article:7
        )

    [2] => Array
        (
            [title] => 文章标题811
            [link] => http://www.youdomain.com/article/811
            [poster] => 104
            [time] => 1465180511
            [votes] => 1
            [id] => article:6
        )

    [3] => Array
        (
            [title] => 文章标题22
            [link] => http://www.youdomain.com/article/22
            [poster] => 103
            [time] => 1465180508
            [votes] => 1
            [id] => article:5
        )

    [4] => Array
        (
            [title] => 文章标题350
            [link] => http://www.youdomain.com/article/350
            [poster] => 102
            [time] => 1465180506
            [votes] => 1
            [id] => article:4
        )

)

<?php

require 'redis.php';

// @param object $redis
// @param int $artile_id
// @param array $to_add
// @param array $to_remove
function add_remove_groups($redis, $article_id, $to_add = [], $to_remove = []) {
	$article = 'article:'.$article_id;
	
	// 将文章添加到所属的群组
	if(! empty($to_add)) {
		foreach($to_add as $group) {
			$redis->sadd('group:'.$group, $article);
		}
	}

	// 将文章从群组里面移除
	if(! empty($to_remove)) {
		foreach($to_remove as $group) {
			$redis->srem('group'.$group, $article);
		}
	}
}

<?php

/* 准备群组数据 */

require 'redis.php';

$article_info = ['article:100408', 'article:100635', 'article:5'];

foreach($article_info as $key => $val) {
	$redis->sadd('group:programming', $val);
}

function get_group_article($redis, $group, $page, $order = 'score:') {
	$key = $order.$group; // 为每个群组的每种排列顺序都创建一个键
	if(! $redis->exists($key)) { // 检查是否已有缓存的排序结果，如果没有的话则进行排序
		$redis->zInter($key, array('group:'.$group, $order), array(1, 1), $aggregate = 'max'); 
		$redis->expire($key, 60); // 60s之后redis删除有序集合
	}
	return get_articles($redis, $page, $key);
}

$group = 'programming';
$page = isset($_GET['page']) ? $_GET['page'] : 1;
$articles = get_group_article($redis, $group, $page);

echo '<pre>';
print_r($articles);