​Redis 实现计数器和限速器的示例代码

<?php
class LikeCounter {
    private $redis;

    public function __construct() {
        $this->redis = new Redis();
        $this->redis->connect('127.0.0.1', 6379);
    }

    public function incrementLike($postId) {
        $key = "post_likes:$postId";
        return $this->redis->incr($key);
    }

    public function getLikeCount($postId) {
        $key = "post_likes:$postId";
        return $this->redis->get($key);
    }
}

// 示例用法
$likeCounter = new LikeCounter();
$postId = 123; // 假设这是某个帖子的ID

// 用户对帖子点赞
$newCount = $likeCounter->incrementLike($postId);
echo "Post $postId has $newCount likes.";

// 获取帖子点赞数
$currentLikes = $likeCounter->getLikeCount($postId);
echo "Current like count for post $postId: $currentLikes";

<?php
class RateLimiter {
    private $redis;
    private $maxRequests;
    private $timeWindow;

    public function __construct($maxRequests, $timeWindow) {
        $this->redis = new Redis();
        $this->redis->connect('127.0.0.1', 6379);
        $this->maxRequests = $maxRequests;
        $this->timeWindow = $timeWindow;
    }

    public function isAllowed($userId, $apiEndpoint) {
        $key = "rate_limit:$userId:$apiEndpoint";
        $count = $this->redis->incr($key);

        if ($count == 1) {
            // 设置过期时间
            $this->redis->expire($key, $this->timeWindow);
        }

        if ($count > $this->maxRequests) {
            // 超过最大请求次数
            return false;
        }

        return true;
    }
}

// 示例用法：每分钟最多允许用户访问API 10次
$rateLimiter = new RateLimiter(10, 60); // 10次请求，时间窗口60秒

$userId = 123; // 假设这是某个用户的ID
$apiEndpoint = "/api/buy"; // API 端点

if ($rateLimiter->isAllowed($userId, $apiEndpoint)) {
    echo "Request allowed.";
    // 执行API操作
} else {
    echo "Too many requests. Please try again later.";
    // 拒绝请求
}

<?php
class SmsRateLimiter {
    private $redis;
    private $maxSmsRequests;
    private $timeWindow;

    public function __construct($maxSmsRequests, $timeWindow) {
        $this->redis = new Redis();
        $this->redis->connect('127.0.0.1', 6379);
        $this->maxSmsRequests = $maxSmsRequests; // 最大允许的短信发送次数
        $this->timeWindow = $timeWindow; // 时间窗口（秒）
    }

    public function canSendSms($userId) {
        $key = "sms_limit:$userId";
        $count = $this->redis->incr($key);

        if ($count == 1) {
            // 第一次操作时，设置过期时间
            $this->redis->expire($key, $this->timeWindow);
        }

        if ($count > $this->maxSmsRequests) {
            // 超过最大允许的发送次数
            return false;
        }

        return true;
    }
}

// 示例用法：限制每个用户每 60 秒最多发送 3 条短信
$smsLimiter = new SmsRateLimiter(3, 60); // 3次请求，时间窗口60秒

$userId = 123; // 假设这是某个用户的ID

if ($smsLimiter->canSendSms($userId)) {
    echo "短信发送成功";
    // 调用发送短信的API
} else {
    echo "发送频率过高，请稍后再试";
    // 拒绝发送短信
}