如何在PHP框架中实施限流和熔断策略以应对高并发

// Redis 限流器
use Predis\Client;

class RedisRateLimiter
{
    private $redis;

    public function __construct(Client $redis)
    {
        $this->redis = $redis;
    }

    public function isAllowed($key, $maxRequests, $timeSpan)
    {
        $count = $this->redis->incr($key);
        if ($count > $maxRequests) {
            $this->redis->expire($key, $timeSpan);
        } else {
            $this->redis->expire($key, time() + $timeSpan);
        }

        return $count <= $maxRequests;
    }
}

// 实战案例
$redisClient = new Predis\Client();
$rateLimiter = new RedisRateLimiter($redisClient);
if ($rateLimiter->isAllowed('api-key', 10, 60)) {
    // 执行请求
} else {
    // 限流，返回错误响应
}

// PHP-CircuitBreaker 库
use circuitbreaker\Breaker;
use circuitbreaker\Storage\RedisStorage;

class CircuitBreaker
{
    private $breaker;

    public function __construct(RedisStorage $storage)
    {
        $this->breaker = new Breaker($storage);
    }

    public function call($callable, ...$args)
    {
        try {
            return $this->breaker->call($callable, ...$args);
        } catch (StateOpenException $e) {
            // 熔断状态，返回错误响应
        } catch (StateHalfOpenException $e) {
            // 半开状态，谨慎执行请求
        }
    }
}

// 实战案例
$storage = new RedisStorage();
$circuitBreaker = new CircuitBreaker($storage);
$circuitBreaker->call(function () {
    // 执行请求
}, []);