实现需求：处理订单过期自动取消，比如下单30分钟未支付自动更改订单状态

实现方案：

1. 使用Redis Key自动过期触发事件通知

2. 使用定时任务30分钟后检查

3. 按照每分钟轮训检查

CREATE TABLE `order_number` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `order_name` varchar(255) DEFAULT NULL,
  `order_status` int(11) DEFAULT NULL,
  `order_token` varchar(255) DEFAULT NULL,
  `order_id` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=20 DEFAULT CHARSET=utf8;

一、使用Redis Key自动过期机制

当我们的key失效时，可以执行我们的客户端回调监听的方法。

需要在Redis中配置：notify-keyspace-events Ex

二、SpringBoot整合key失效监听

@Configuration
public class RedisListenerConfig {
    @Bean
    RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory) {
        RedisMessageListenerContainer container = new RedisMessageListenerContainer();
        container.setConnectionFactory(connectionFactory);
        return container;
    }
}

@Component
public class RedisKeyExpirationListener extends KeyExpirationEventMessageListener {
    public RedisKeyExpirationListener(RedisMessageListenerContainer listenerContainer) {
        super(listenerContainer);
    }

    /**
     * 待支付
     */
    private static final Integer ORDER_STAYPAY = 0;
    /**
     * 失效
     */
    private static final Integer ORDER_INVALID = 2;
    @Autowired
    private OrderMapper orderMapper;

    /**
     * Redis失效事件 key
     *
     * @param message
     * @param pattern
     */
    @Override
    public void onMessage(Message message, byte[] pattern) {
        String expiraKey = message.toString();
        // 根据key查询 value 如果还还是为待支付状态 将订单改为已经超时~~
        OrderEntity orderNumber = orderMapper.getOrderNumber(expiraKey);
        System.out.println(expiraKey);
        if (orderNumber == null) {
            return;
        }
        if (orderNumber.getOrderStatus().equals(ORDER_STAYPAY)) {
            // 将订单状态改为已经失效
            orderMapper.updateOrderStatus(expiraKey, ORDER_INVALID);
        }
    }
}

@RestController
public class OrderController {
    @Autowired
    private OrderMapper orderMapper;
    @Autowired
    private RedisUtils redisUtils;

    @RequestMapping("/saveOrder")
    public String saveOrder() {
        // 1.生成token
        String orderToken = UUID.randomUUID().toString();
        String orderId = System.currentTimeMillis() + "";
        //2. 将该token存放到redis中
        redisUtils.setString(orderToken, orderId, 5L);
        OrderEntity orderEntity = new OrderEntity(null, "会员", orderId, orderToken);
        int result = orderMapper.insertOrder(orderEntity);
        return result > 0 ? "success" : "fail";
    }
}

@Data
public class OrderEntity {
    private Long id;
    private String orderName;
    /**
     * 0 待支付 1 已经支付
     */
    private Integer orderStatus;

    private String orderToken;
    private String orderId;

    public OrderEntity(Long id, String orderName, String orderId, String orderToken) {
        this.id = id;
        this.orderName = orderName;
        this.orderId = orderId;
        this.orderToken = orderToken;
    }
}

public interface OrderMapper {

    @Insert("insert into order_number values (null,#{orderName},0,#{orderToken},#{orderId})")
    int insertOrder(OrderEntity OrderEntity);


    @Select("SELECT ID AS ID ,order_name AS ORDERNAME ,order_status AS orderstatus,order_token as ordertoken,order_id as  orderid FROM order_number\n" +
            "where order_token=#{orderToken};")
    OrderEntity getOrderNumber(String orderToken);

    @Update("\n" +
            "\n" +
            "update order_number set order_status=#{orderStatus} where order_token=#{orderToken};")
    int updateOrderStatus(String orderToken, Integer orderStatus);
}