PHP 인스턴트 킬링 시스템의 데이터 일관성 보장 조치

// 获取商品信息和库存
$sql = "SELECT stock FROM goods WHERE id = 1";
$result = $db->query($sql);
$row = $result->fetch_assoc();
$stock = $row['stock'];

// 判断库存是否足够
if ($stock > 0) {
    // 生成订单并更新库存
    $sql = "INSERT INTO orders (goods_id) VALUES (1)";
    $db->query($sql);
    
    $sql = "UPDATE goods SET stock = stock - 1 WHERE id = 1 AND stock = $stock";
    $db->query($sql);
    if ($db->affected_rows == 0) {
        // 更新失败，抢购失败
    } else {
        // 抢购成功
    }
} else {
    // 库存不足，抢购失败
}

// 加锁
$redis = new Redis();
$redis->connect('127.0.0.1', 6379);
$lockKey = 'goods:1:lock';
$timeout = 10;
$expire = time() + $timeout;

while (true) {
    $isLock = $redis->setnx($lockKey, $expire);
    if ($isLock || ($redis->get($lockKey) < time() && $redis->getSet($lockKey, $expire) < time())) {
        // 加锁成功，执行抢购操作
        // ...
        // 释放锁
        $redis->del($lockKey);
        break;
    }
}

// 生产者端代码
$exchangeName = 'seckill_exchange';
$queueName = 'seckill_queue';
$routingKey = 'seckill_key';

$connection = new AMQPStreamConnection('127.0.0.1', 5672, 'guest', 'guest');
$channel = $connection->channel();
$channel->exchange_declare($exchangeName, 'direct', false, true, false);
$channel->queue_declare($queueName, false, true, false, false);
$channel->queue_bind($queueName, $exchangeName, $routingKey);

$msgBody = 'User A wants to buy Goods 1';
$msg = new AMQPMessage($msgBody, ['delivery_mode' => AMQPMessage::DELIVERY_MODE_PERSISTENT]);
$channel->basic_publish($msg, $exchangeName, $routingKey);

$channel->close();
$connection->close();

// 消费者端代码
$callback = function ($msg) {
    // 处理抢购请求
    // ...
    
    $msg->ack();
};

$connection = new AMQPStreamConnection('127.0.0.1', 5672, 'guest', 'guest');
$channel = $connection->channel();
$channel->queue_declare($queueName, false, true, false, false);
$channel->basic_qos(null, 1, null);
$channel->basic_consume($queueName, '', false, false, false, false, $callback);

while (count($channel->callbacks)) {
    $channel->wait();
}

$channel->close();
$connection->close();