-- 1.参数列表
-- 1.1.优惠券id
local voucherId = ARGV[1]
-- 1.2.用户id
local userId = ARGV[2]
-- 1.3.订单id
local orderId = ARGV[3]

-- 2.数据key
-- 2.1.库存key
local stockKey = 'seckill:stock:' .. voucherId
-- 2.2.订单key
local orderKey = 'seckill:order:' .. voucherId

-- 3.脚本业务
-- 3.1.判断库存是否充足 get stockKey
if(tonumber(redis.call('get', stockKey)) <= 0) then
-- 3.2.库存不足，返回1
return 1
end
-- 3.2.判断用户是否下单 SISMEMBER orderKey userId
if(redis.call('sismember', orderKey, userId) == 1) then
-- 3.3.存在，说明是重复下单，返回2
return 2
end
-- 3.4.扣库存 incrby stockKey -1
redis.call('incrby', stockKey, -1)
-- 3.5.下单（保存用户）sadd orderKey userId
redis.call('sadd', orderKey, userId)
-- 3.6.发送消息到队列中， XADD stream.orders * k1 v1 k2 v2 ...
redis.call('xadd', 'stream.orders', '*', 'userId', userId, 'voucherId', voucherId, 'id', orderId)
return 0

private class VoucherOrderHandler implements Runnable {
String queueName = "stream.orders";
@Override
public void run() {
while (true) {
try {
// 1. 获取消息队列中的信息 XREADGROUP GROUP g1 c1 COUNT 1 BLOCK 2000 STREAMS stream.order >
List<MapRecord<String, Object, Object>> list = stringRedisTemplate.opsForStream().read(
Consumer.from("g1", "c1"),
StreamReadOptions.empty().count(1).block(Duration.ofSeconds(2)),
StreamOffset.create(queueName, ReadOffset.lastConsumed())
);
// 2. 判断消息获取是否成功
if (list == null || list.isEmpty()) {
// 2.1 获取失败，没有消息，进行下一次循环
continue;
}
// 3. 解析消息中的订单信息
MapRecord<String, Object, Object> record = list.get(0);
Map<Object, Object> values = record.getValue();
VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(values, new VoucherOrder(), true);
// 3. 获取成功，可以下单
handleVoucherOrder(voucherOrder);
// 4. ACK确认 XACK stream.orders g1 id
stringRedisTemplate.opsForStream().acknowledge(queueName, "g1", record.getId());
} catch (Exception e) {
log.error("处理订单异常");
handlePendingLists();
}
}
}

private void handlePendingLists() {
while (true) {
try {
// 1. 获取pendingList队列中的信息 XREADGROUP GROUP g1 c1 COUNT 1 STREAMS stream.order 0
List<MapRecord<String, Object, Object>> list = stringRedisTemplate.opsForStream().read(
Consumer.from("g1", "c1"),
StreamReadOptions.empty().count(1),
StreamOffset.create(queueName, ReadOffset.from("0"))
);
// 2. 判断消息获取是否成功
if (list == null || list.isEmpty()) {
// 2.1 获取失败，说明pending-list没有消息，结束循环
break;
}
// 3. 解析消息中的订单信息
MapRecord<String, Object, Object> record = list.get(0);
Map<Object, Object> values = record.getValue();
VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(values, new VoucherOrder(), true);
// 3. 获取成功，可以下单
handleVoucherOrder(voucherOrder);
// 4. ACK确认 XACK stream.orders g1 id
stringRedisTemplate.opsForStream().acknowledge(queueName, "g1", record.getId());
} catch (Exception e) {
log.error("处理pend-list订单异常", e);
try {
Thread.sleep(20);
} catch (InterruptedException ex) {
ex.printStackTrace();
}
}
}
}
}