支付退款申请，支付宝手机wap 相应实现

2025-07-25 16:35:06 +08:00 · 2021-11-21 11:12:32 +08:00
parent 19f554176c
commit 7d6f205dc0
41 changed files with 1519 additions and 61 deletions
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/convert/order/PayRefundCoreConvert.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/convert/order/PayRefundCoreConvert.java
@ -0,0 +1,26 @@
+package cn.iocoder.yudao.coreservice.modules.pay.convert.order;
+
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundPostReqBO;
+import cn.iocoder.yudao.framework.pay.core.client.dto.PayRefundUnifiedRespDTO;
+import org.mapstruct.Mapper;
+import org.mapstruct.factory.Mappers;
+import org.mapstruct.Mapping;
+import org.mapstruct.Mappings;
+
+@Mapper
+public interface PayRefundCoreConvert {
+
+    PayRefundCoreConvert INSTANCE = Mappers.getMapper(PayRefundCoreConvert.class);
+
+    PayRefundPostReqBO convert(PayRefundUnifiedRespDTO respDTO);
+
+    //TODO 太多需要处理了， 暂时不用
+    @Mappings(value = {
+            @Mapping(source = "amount", target = "payAmount"),
+            @Mapping(source = "id", target = "orderId"),
+            @Mapping(target = "status",ignore = true)
+    })
+    PayRefundDO convert(PayOrderDO orderDO);
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/dal/dataobject/order/PayOrderDO.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/dal/dataobject/order/PayOrderDO.java
@ -4,7 +4,7 @@ import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.merchant.PayAppDO
 import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.merchant.PayChannelDO;
 import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.merchant.PayMerchantDO;
 import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayOrderNotifyStatusEnum;
-import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayOrderRefundStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundTypeEnum;
 import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayOrderStatusEnum;
 import cn.iocoder.yudao.framework.mybatis.core.dataobject.BaseDO;
 import cn.iocoder.yudao.framework.pay.core.enums.PayChannelEnum;
@ -135,7 +135,7 @@ public class PayOrderDO extends BaseDO {
    /**
     * 退款状态
     *
-     * 枚举 {@link PayOrderRefundStatusEnum}
+     * 枚举 {@link PayRefundTypeEnum}
     */
    private Integer refundStatus;
    /**
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/dal/dataobject/order/PayRefundDO.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/dal/dataobject/order/PayRefundDO.java
@ -5,7 +5,9 @@ import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.merchant.PayChann
 import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.merchant.PayMerchantDO;
 import cn.iocoder.yudao.framework.pay.core.enums.PayChannelEnum;
 import cn.iocoder.yudao.framework.mybatis.core.dataobject.BaseDO;
-import lombok.Data;
+import com.baomidou.mybatisplus.annotation.TableId;
+import com.baomidou.mybatisplus.annotation.TableName;
+import lombok.*;

 import java.util.Date;

@ -17,19 +19,34 @@ import java.util.Date;
 *
 * @author 芋道源码
 */
+@TableName("pay_refund")
@Data
+@EqualsAndHashCode(callSuper = true)
+@ToString(callSuper = true)
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
 public class PayRefundDO extends BaseDO {

    /**
     * 退款单编号，数据库自增
     */
+    @TableId
    private Long id;
-    /**
-     * 退款单号，根据规则生成
-     *
+
+     /**
+     * https://api.mch.weixin.qq.com/v3/refund/domestic/refunds 中的 out_refund_no
+     * https://opendocs.alipay.com/apis alipay.trade.refund 中的 out_request_no
+     * 退款请求号。
+     * 标识一次退款请求，需要保证在交易号下唯一，如需部分退款，则此参数必传。
+     * 注：针对同一次退款请求，如果调用接口失败或异常了，重试时需要保证退款请求号不能变更，
+     * 防止该笔交易重复退款。支付宝会保证同样的退款请求号多次请求只会退一次。
+     * 退款单请求号，根据规则生成
+      *
     * 例如说，R202109181134287570000
     */
-    private String no;
+    private String reqNo;
+
    /**
     * 商户编号
     *
@ -61,23 +78,39 @@ public class PayRefundDO extends BaseDO {
     */
    private Long orderId;

+
+    /**
+     * 交易订单号，根据规则生成
+     * 调用支付渠道时，使用该字段作为对接的订单号。
+     * 1. 调用微信支付 https://api.mch.weixin.qq.com/pay/unifiedorder 时，使用该字段作为 out_trade_no
+     * 2. 调用支付宝 https://opendocs.alipay.com/apis 时，使用该字段作为 out_trade_no
+     *  这里对应 pay_extension 里面的 no
+     * 例如说，P202110132239124200055
+     */
+    private String tradeNo;
+
+
    // ========== 商户相关字段 ==========
    /**
-     * 商户退款订单号
-     * 例如说，内部系统 A 的退款订单号。需要保证每个 PayMerchantDO 唯一 TODO 芋艿：需要在测试下
+     * 商户订单编号
+     */
+    private String merchantOrderId;
+    /**
+     * 商户退款订单号, 由商户系统产生， 由他们保证唯一，不能为空，通知商户时会传该字段。发送channel 使用 reqNo
+     * 例如说，内部系统 A 的退款订单号。需要保证每个 PayMerchantDO 唯一
+     * TODO 芋艿：我理解 一个商户退款订单，可以对应多条退款记录， 因为有可能失败。但是 退款请求号 reqNo 必须唯一
+     *
     */
    private String merchantRefundNo;
-//    /**
-//     * 商户拓展参数
-//     */
-//    private String merchantExtra;
+
    /**
     * 异步通知地址
     */
    private String notifyUrl;
+
    /**
     * 通知商户退款结果的回调状态
-     * TODO 芋艿：0 未发送 1 已发送
+     * TODO 0 未发送 1 已发送
     */
    private Integer notifyStatus;

@ -85,44 +118,76 @@ public class PayRefundDO extends BaseDO {
    /**
     * 退款状态
     *
-     * TODO 芋艿：状态枚举
     */
    private Integer status;
+
    /**
-     * 用户 IP
+     * 退款类型(部分退款，全部退款)
     */
-    private String userIp;
+    private Integer type;
    /**
-     * 退款金额，单位：分
+     * 支付金额,单位分
     */
-    private Long amount;
+    private Long payAmount;
+    /**
+     * 退款金额,单位分
+     */
+    private Long refundAmount;
+
    /**
     * 退款原因
     */
    private String reason;
+
+
    /**
-     * 订单退款成功时间
+     * 用户 IP
     */
-    private Date successTime;
+    private String userIp;
+
+    // ========== 渠道相关字段 ==========
    /**
+     * 渠道订单号，pay_order 中的channel_order_no 对应
+     */
+    private String channelOrderNo;
+    /**
+     * 渠道退款单号，渠道返回
+     */
+    private String channelRefundNo;
+
+    /**
+     * 调用渠道的错误码
+     */
+    private String channelErrorCode;
+
+    /**
+     * 调用渠道报错时，错误信息
+     */
+    private String channelErrorMsg;
+
+
+    /**
+     * 支付渠道的额外参数
+     * 参见 https://www.pingxx.com/api/Refunds%20退款概述.html
+     */
+    private String channelExtras;
+
+
+    /**
+     * TODO
     * 退款失效时间
     */
    private Date expireTime;
    /**
-     * 支付渠道的额外参数
-     *
-     * 参见 https://www.pingxx.com/api/Refunds%20退款概述.html
+     * 退款成功时间
     */
-    private String channelExtra;
+    private Date successTime;
+    /**
+     * 退款通知时间
+     */
+    private Date notifyTime;
+
+

-    // ========== 渠道相关字段 ==========
-    /**
-     * 渠道订单号
-     */
-    private String channelOrderNo;
-    /**
-     * 渠道退款号
-     */
-    private String channelRefundNo;

 }
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/dal/mysql/order/PayRefundMapper.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/dal/mysql/order/PayRefundMapper.java
@ -0,0 +1,21 @@
+package cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order;
+
+import java.util.*;
+
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.framework.common.pojo.PageResult;
+import cn.iocoder.yudao.framework.mybatis.core.query.QueryWrapperX;
+import cn.iocoder.yudao.framework.mybatis.core.mapper.BaseMapperX;
+
+import org.apache.ibatis.annotations.Mapper;
+
+
+/**
+ * 退款订单 Mapper
+ *
+ */
+@Mapper
+public interface PayRefundMapper extends BaseMapperX<PayRefundDO> {
+
+
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/enums/PayErrorCodeCoreConstants.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/enums/PayErrorCodeCoreConstants.java
@ -28,6 +28,12 @@ public interface PayErrorCodeCoreConstants {
    ErrorCode PAY_ORDER_EXTENSION_STATUS_IS_NOT_WAITING = new ErrorCode(1007003001, "支付交易拓展单不处于待支付");
    ErrorCode PAY_ORDER_EXTENSION_STATUS_IS_NOT_SUCCESS = new ErrorCode(1007003002, "支付订单不处于已支付");

+    // ========== 支付模块(退款) 1-007-006-000 ==========
+    ErrorCode PAY_REFUND_AMOUNT_EXCEED = new ErrorCode(1007006000, "退款金额超过订单可退款金额");
+    ErrorCode PAY_REFUND_ALL_REFUNDED = new ErrorCode(1007006001, "订单已经全额退款");
+    ErrorCode PAY_REFUND_CHN_ORDER_NO_IS_NULL = new ErrorCode(1007006002, "该订单的渠道订单为空");
+    ErrorCode PAY_REFUND_POST_HANDLER_NOT_FOUND = new ErrorCode(1007006002, "未找到对应的退款后置处理类");
+
    /**
     * ========== 支付商户信息 1-007-004-000 ==========
     */
@ -41,11 +47,11 @@ public interface PayErrorCodeCoreConstants {


    /**
-     * ========== 支付渠道 1-007-006-000 ==========
+     * ========== 支付渠道 1-007-001-000 ==========
     */
-    ErrorCode CHANNEL_NOT_EXISTS = new ErrorCode(1007006000, "支付渠道不存在");
-    ErrorCode CHANNEL_KEY_READ_ERROR = new ErrorCode(1007006002, "支付渠道秘钥文件读取失败");
+    ErrorCode CHANNEL_NOT_EXISTS = new ErrorCode(1007001003, "支付渠道不存在");
+    ErrorCode CHANNEL_KEY_READ_ERROR = new ErrorCode(1007001004, "支付渠道秘钥文件读取失败");
    // TODO @aquan：下面这个错误码，缺了 CHANNEL 前缀。另外，错误码的分段，上面有啦，合并下进去哈
-    ErrorCode EXIST_SAME_CHANNEL_ERROR = new ErrorCode(1007006003, "已存在相同的渠道");
+    ErrorCode EXIST_SAME_CHANNEL_ERROR = new ErrorCode(1007001005, "已存在相同的渠道");

 }
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/enums/order/PayRefundStatusEnum.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/enums/order/PayRefundStatusEnum.java
@ -0,0 +1,20 @@
+package cn.iocoder.yudao.coreservice.modules.pay.enums.order;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@Getter
+@AllArgsConstructor
+public enum PayRefundStatusEnum {
+    CREATE(0, "退款订单生成"),
+    SUCCESS(1, "退款成功"),
+    FAILURE(2, "退款失败"),
+    PROCESSING_NOTIFY(3,"退款中, 渠道通知结果"),
+    PROCESSING_QUERY(4,"退款中, 系统查询结果"),
+    UNKNOWN_RETRY(5,"状态未知，需要重试"),
+    UNKNOWN_QUERY(6,"状态未知，系统查询结果"),
+    CLOSE(99, "退款关闭");
+
+    private final Integer status;
+    private final String name;
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/enums/order/PayOrderRefundStatusEnum.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/enums/order/PayOrderRefundStatusEnum.java
@ -11,7 +11,7 @@ import lombok.Getter;
 */
@Getter
@AllArgsConstructor
-public enum PayOrderRefundStatusEnum implements IntArrayValuable {
+public enum PayRefundTypeEnum implements IntArrayValuable {

    NO(0, "未退款"),
    SOME(10, "部分退款"),
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/notify/impl/PayNotifyCoreServiceImpl.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/notify/impl/PayNotifyCoreServiceImpl.java
@ -5,8 +5,10 @@ import cn.hutool.http.HttpUtil;
 import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.notify.PayNotifyLogDO;
 import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.notify.PayNotifyTaskDO;
 import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
 import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.notify.PayNotifyLogCoreMapper;
 import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.notify.PayNotifyTaskCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayRefundMapper;
 import cn.iocoder.yudao.coreservice.modules.pay.dal.redis.notify.PayNotifyLockCoreRedisDAO;
 import cn.iocoder.yudao.coreservice.modules.pay.enums.notify.PayNotifyStatusEnum;
 import cn.iocoder.yudao.coreservice.modules.pay.enums.notify.PayNotifyTypeEnum;
@ -72,6 +74,9 @@ public class PayNotifyCoreServiceImpl implements PayNotifyCoreService {
    @Resource
    private PayNotifyLockCoreRedisDAO payNotifyLockCoreRedisDAO;

+    @Resource
+    private PayRefundMapper  payRefundMapper;
+
    @Resource
    @Lazy // 循环依赖（自己依赖自己），避免报错
    private PayNotifyCoreServiceImpl self;
@ -89,7 +94,9 @@ public class PayNotifyCoreServiceImpl implements PayNotifyCoreService {
                    setMerchantOrderId(order.getMerchantOrderId()).setNotifyUrl(order.getNotifyUrl());
        } else if (Objects.equals(task.getType(), PayNotifyTypeEnum.REFUND.getType())) {
            // TODO 芋艿，需要实现下哈
-            throw new UnsupportedOperationException("需要实现");
+            PayRefundDO refundDO = payRefundMapper.selectById(task.getDataId());
+            task.setMerchantId(refundDO.getMerchantId()).setAppId(refundDO.getAppId())
+                    .setMerchantOrderId(refundDO.getMerchantOrderId()).setNotifyUrl(refundDO.getNotifyUrl());
        }

        // 执行插入
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/notify/vo/PayRefundOrderReqVO.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/notify/vo/PayRefundOrderReqVO.java
@ -17,12 +17,15 @@ import javax.validation.constraints.NotNull;
@AllArgsConstructor
 public class PayRefundOrderReqVO {

-    @ApiModelProperty(value = "商户订单编号", required = true, example = "10")
-    @NotEmpty(message = "商户订单号不能为空")
+    @ApiModelProperty(value = "商户退款单编号", required = true, example = "10")
+    @NotEmpty(message = "商户退款单编号不能为空")
    private String merchantOrderId;

    @ApiModelProperty(value = "支付退款编号", required = true, example = "20")
    @NotNull(message = "支付退款编号不能为空")
    private Long payRefundId;

+    @ApiModelProperty(value = "退款状态(成功，失败)", required = true, example = "10")
+    private Integer status;
+
 }
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/PayOrderCoreService.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/PayOrderCoreService.java
@ -2,9 +2,7 @@ package cn.iocoder.yudao.coreservice.modules.pay.service.order;

 import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;

-import cn.iocoder.yudao.coreservice.modules.pay.service.order.dto.PayOrderCreateReqDTO;
-import cn.iocoder.yudao.coreservice.modules.pay.service.order.dto.PayOrderSubmitReqDTO;
-import cn.iocoder.yudao.coreservice.modules.pay.service.order.dto.PayOrderSubmitRespDTO;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.dto.*;
 import cn.iocoder.yudao.framework.pay.core.client.dto.PayNotifyDataDTO;

 import javax.validation.Valid;
@ -50,4 +48,6 @@ public interface PayOrderCoreService {
    */
   void notifyPayOrder(Long channelId, String channelCode, PayNotifyDataDTO notifyData) throws Exception;

+
+
 }
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/PayRefundAbstractChannelPostHandler.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/PayRefundAbstractChannelPostHandler.java
@ -0,0 +1,40 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order;
+
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayOrderCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayRefundMapper;
+
+/**
+ * 支付退款订单渠道返回后 , 后置处理抽象类， 处理公用的逻辑
+ * @author  jason
+ */
+public abstract  class PayRefundAbstractChannelPostHandler implements PayRefundChannelPostHandler {
+
+    private final PayOrderCoreMapper payOrderCoreMapper;
+    private final PayRefundMapper payRefundMapper;
+
+    public PayRefundAbstractChannelPostHandler(PayOrderCoreMapper payOrderCoreMapper,
+                                               PayRefundMapper payRefundMapper){
+        this.payOrderCoreMapper = payOrderCoreMapper;
+        this.payRefundMapper = payRefundMapper;
+    }
+
+
+    /**
+     * 更新退款单
+     * @param refundDO  需要更新的退款单信息
+     */
+    protected void updatePayRefund(PayRefundDO refundDO){
+        payRefundMapper.updateById(refundDO);
+    }
+
+
+    /**
+     * 更新原始支付订单
+     * @param payOrderDO 支付订单信息
+     */
+    protected void updatePayOrder(PayOrderDO payOrderDO){
+        payOrderCoreMapper.updateById(payOrderDO);
+    }
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/PayRefundChannelPostHandler.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/PayRefundChannelPostHandler.java
@ -0,0 +1,24 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order;
+
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundPostReqBO;
+import cn.iocoder.yudao.framework.pay.core.enums.PayChannelRespEnum;
+
+/**
+ * 支付退款订单 ，渠道返回后 后置处理
+ * @author jason
+ */
+public interface PayRefundChannelPostHandler {
+
+    /**
+     * 支持的渠道返回值
+     * @return 支持的渠道返回值数组
+     */
+    PayChannelRespEnum[] supportHandleResp();
+
+
+    /**
+     * 根据渠道返回， 处理支付退款单
+     * @param respBO
+     */
+    void handleRefundChannelResp(PayRefundPostReqBO respBO);
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/PayRefundCoreService.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/PayRefundCoreService.java
@ -0,0 +1,20 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order;
+
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundReqBO;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundRespBO;
+
+/**
+ * 退款单 Core Service
+ *
+ * @author jason
+ */
+public interface PayRefundCoreService {
+
+
+    /**
+     * 提交退款申请
+     * @param reqDTO 退款申请信息
+     * @return 退款申请返回信息
+     */
+    PayRefundRespBO refund(PayRefundReqBO reqDTO);
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/bo/PayRefundPostReqBO.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/bo/PayRefundPostReqBO.java
@ -0,0 +1,96 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.bo;
+
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundTypeEnum;
+import cn.iocoder.yudao.framework.pay.core.enums.PayChannelRespEnum;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import lombok.experimental.Accessors;
+
+@Data
+@Accessors(chain = true)
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class PayRefundPostReqBO {
+
+
+    /**
+     * 渠道的通用返回结果
+     */
+    private PayChannelRespEnum respEnum;
+
+
+
+    private PayRefundTypeEnum refundTypeEnum;
+
+    /**
+     * 已退款的总金额
+     */
+    private Long  refundedAmount;
+
+    /**
+     * 本次退款金额
+     */
+    private Long refundAmount;
+
+   /**
+     * 已退款次数
+     */
+    private Integer refundedTimes;
+
+
+    /**
+     * 订单编号
+     */
+    private Long  orderId;
+
+    /**
+     * 退款单编号
+     */
+    private Long refundId;
+
+
+    /**
+     * 渠道退款单号
+     */
+    private String channelRefundNo;
+
+
+    /**
+     * https://api.mch.weixin.qq.com/v3/refund/domestic/refunds 中的 out_trade_no
+     * https://opendocs.alipay.com/apis alipay.trade.refund 中的 out_trade_no
+     * 支付交易号 {PayOrderExtensionDO no字段} 和 渠道订单号 不能同时为空
+     */
+    private String payTradeNo;
+
+
+    /**
+     * https://api.mch.weixin.qq.com/v3/refund/domestic/refunds 中的 out_refund_no
+     * https://opendocs.alipay.com/apis alipay.trade.refund 中的 out_request_no
+     * 退款请求单号  同一退款请求单号多次请求只退一笔。
+     */
+    private String refundReqNo;
+
+
+
+    /**
+     * 调用异常错误信息
+     */
+    private String exceptionMsg;
+
+
+    /**
+     * 渠道的错误码
+     */
+    private String channelErrCode;
+
+
+    /**
+     * 渠道的错误描述
+     */
+    private String channelErrMsg;
+
+
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/bo/PayRefundReqBO.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/bo/PayRefundReqBO.java
@ -0,0 +1,43 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.bo;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import lombok.experimental.Accessors;
+/**
+ * 退款申请单 Request DTO
+ */
+@Data
+@Accessors(chain = true)
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class PayRefundReqBO {
+
+    /**
+     * 支付订单编号自增
+     */
+    private Long payOrderId;
+
+    /**
+     * 退款金额
+     */
+    private Long amount;
+
+    /**
+     * 退款原因
+     */
+    private String reason;
+
+
+    /**
+     * 商户退款订单号
+     */
+    private String merchantRefundNo;
+
+    /**
+     * 用户 IP
+     */
+    private String userIp;
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/bo/PayRefundRespBO.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/bo/PayRefundRespBO.java
@ -0,0 +1,23 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.bo;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import lombok.experimental.Accessors;
+
+/**
+ * 退款申请单 Response DTO
+ */
+@Data
+@Accessors(chain = true)
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class PayRefundRespBO {
+
+    /**
+     * 支付退款单编号， 自增
+     */
+    private Long refundId;
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelFailedHandler.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelFailedHandler.java
@ -0,0 +1,62 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.impl;
+
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayOrderCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayRefundMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.notify.PayNotifyTypeEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.service.notify.PayNotifyCoreService;
+import cn.iocoder.yudao.coreservice.modules.pay.service.notify.dto.PayNotifyTaskCreateReqDTO;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.PayRefundAbstractChannelPostHandler;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundPostReqBO;
+import cn.iocoder.yudao.framework.pay.core.enums.PayChannelRespEnum;
+import org.springframework.stereotype.Service;
+
+import javax.annotation.Resource;
+import java.util.Optional;
+
+/**
+ * 支付退款订单渠道返回失败的后置处理类
+ * {@link PayChannelRespEnum#CALL_EXCEPTION}
+ * {@link PayChannelRespEnum#CAN_NOT_RETRY_FAILURE}
+ */
+@Service
+public class PayRefundChannelFailedHandler extends PayRefundAbstractChannelPostHandler {
+
+    @Resource
+    private PayNotifyCoreService payNotifyCoreService;
+
+    public PayRefundChannelFailedHandler(PayOrderCoreMapper payOrderCoreMapper, PayRefundMapper payRefundMapper) {
+        super(payOrderCoreMapper, payRefundMapper);
+    }
+
+    @Override
+    public PayChannelRespEnum[] supportHandleResp() {
+        return new PayChannelRespEnum[] {PayChannelRespEnum.CALL_EXCEPTION, PayChannelRespEnum.CAN_NOT_RETRY_FAILURE};
+    }
+
+
+    @Override
+    public void handleRefundChannelResp(PayRefundPostReqBO respBO) {
+        //退款失败
+        //更新退款单表
+        PayRefundDO updateRefundDO = new PayRefundDO();
+
+        updateRefundDO.setId(respBO.getRefundId())
+                .setStatus(PayRefundStatusEnum.FAILURE.getStatus())
+                .setChannelErrorCode(respBO.getChannelErrCode())
+                .setChannelErrorMsg(Optional.ofNullable(respBO.getChannelErrMsg())
+                                          .orElse(respBO.getExceptionMsg()));
+        updatePayRefund(updateRefundDO);
+        PayOrderDO updateOrderDO = new PayOrderDO();
+        //更新订单表
+        updateOrderDO.setId(respBO.getOrderId())
+                .setRefundTimes(respBO.getRefundedTimes() + 1);
+        updatePayOrder(updateOrderDO);
+        // 立刻插入退款通知记录
+        // TODO 通知商户成功或者失败. 现在通知似乎没有实现， 只是回调
+        payNotifyCoreService.createPayNotifyTask(PayNotifyTaskCreateReqDTO.builder()
+                .type(PayNotifyTypeEnum.REFUND.getType()).dataId(respBO.getRefundId()).build());
+    }
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelNotifyHandler.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelNotifyHandler.java
@ -0,0 +1,45 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.impl;
+
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayOrderCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayRefundMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.PayRefundAbstractChannelPostHandler;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundPostReqBO;
+import cn.iocoder.yudao.framework.pay.core.enums.PayChannelRespEnum;
+import org.springframework.stereotype.Service;
+
+/**
+ * 支付退款订单渠道返回通知 {@link PayChannelRespEnum#PROCESSING_NOTIFY}，后置处理类
+ * 支付宝退款单好像没有回调， 微信会触发回调
+ */
+@Service
+public class PayRefundChannelNotifyHandler extends PayRefundAbstractChannelPostHandler {
+
+    public PayRefundChannelNotifyHandler(PayOrderCoreMapper payOrderCoreMapper,
+                                         PayRefundMapper payRefundMapper) {
+        super(payOrderCoreMapper, payRefundMapper);
+    }
+
+    @Override
+    public PayChannelRespEnum[] supportHandleResp() {
+        return new PayChannelRespEnum[] {PayChannelRespEnum.PROCESSING_NOTIFY};
+    }
+
+    @Override
+    public void handleRefundChannelResp(PayRefundPostReqBO respBO) {
+        PayRefundDO updateRefundDO = new PayRefundDO();
+        //更新退款单表
+        updateRefundDO.setId(respBO.getRefundId())
+                .setStatus(PayRefundStatusEnum.PROCESSING_NOTIFY.getStatus());
+        updatePayRefund(updateRefundDO);
+
+        PayOrderDO updateOrderDO = new PayOrderDO();
+        //更新订单表
+        updateOrderDO.setId(respBO.getOrderId())
+                .setRefundTimes(respBO.getRefundedTimes() + 1);
+        updatePayOrder(updateOrderDO);
+
+    }
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelQueryHandler.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelQueryHandler.java
@ -0,0 +1,54 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.impl;
+
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayOrderCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayRefundMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.PayRefundAbstractChannelPostHandler;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundPostReqBO;
+import cn.iocoder.yudao.framework.pay.core.enums.PayChannelRespEnum;
+import org.springframework.stereotype.Service;
+
+import java.util.Objects;
+
+/**
+ * 支付退款订单渠道返回需调用查询接口的后置处理类
+ * {@link PayChannelRespEnum#PROCESSING_QUERY} //TODO 芋道源码 是不是微信有这样的情况
+ * {@link PayChannelRespEnum#READ_TIME_OUT_EXCEPTION}
+ */
+@Service
+public class PayRefundChannelQueryHandler extends PayRefundAbstractChannelPostHandler {
+
+
+    public PayRefundChannelQueryHandler(PayOrderCoreMapper payOrderCoreMapper,
+                                        PayRefundMapper payRefundMapper) {
+        super(payOrderCoreMapper, payRefundMapper);
+    }
+
+    @Override
+    public PayChannelRespEnum[] supportHandleResp() {
+        return new PayChannelRespEnum[]{PayChannelRespEnum.PROCESSING_QUERY, PayChannelRespEnum.READ_TIME_OUT_EXCEPTION};
+    }
+
+    @Override
+    public void handleRefundChannelResp(PayRefundPostReqBO respBO) {
+        final PayChannelRespEnum respEnum = respBO.getRespEnum();
+        PayRefundStatusEnum refundStatus =
+                Objects.equals(PayChannelRespEnum.PROCESSING_QUERY, respEnum) ? PayRefundStatusEnum.PROCESSING_QUERY
+                        : PayRefundStatusEnum.UNKNOWN_QUERY;
+        //更新退款单表
+        PayRefundDO updateRefundDO = new PayRefundDO();
+        updateRefundDO.setId(respBO.getRefundId())
+                .setStatus(refundStatus.getStatus());
+        updatePayRefund(updateRefundDO);
+
+        PayOrderDO updateOrderDO = new PayOrderDO();
+        //更新订单表
+        updateOrderDO.setId(respBO.getOrderId())
+                .setRefundTimes(respBO.getRefundedTimes() + 1);
+        updatePayOrder(updateOrderDO);
+
+        //TODO 发起查询任务
+    }
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelRetryHandler.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelRetryHandler.java
@ -0,0 +1,52 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.impl;
+
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayOrderCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayRefundMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.PayRefundAbstractChannelPostHandler;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundPostReqBO;
+import cn.iocoder.yudao.framework.pay.core.enums.PayChannelRespEnum;
+import org.springframework.stereotype.Service;
+
+import java.util.Optional;
+
+/**
+ * 支付退款订单渠道返回重试的后置处理类
+ * {@link PayChannelRespEnum#RETRY_FAILURE}
+ */
+@Service
+public class PayRefundChannelRetryHandler extends PayRefundAbstractChannelPostHandler {
+
+
+    public PayRefundChannelRetryHandler(PayOrderCoreMapper payOrderCoreMapper,
+                                        PayRefundMapper payRefundMapper) {
+        super(payOrderCoreMapper, payRefundMapper);
+    }
+
+    @Override
+    public PayChannelRespEnum[] supportHandleResp() {
+        return new PayChannelRespEnum[] {PayChannelRespEnum.RETRY_FAILURE};
+    }
+
+    @Override
+    public void handleRefundChannelResp(PayRefundPostReqBO respBO) {
+
+        PayRefundDO updateRefundDO = new PayRefundDO();
+        //更新退款单表
+        updateRefundDO.setId(respBO.getRefundId())
+                .setStatus(PayRefundStatusEnum.UNKNOWN_RETRY.getStatus())
+                .setChannelErrorCode(respBO.getChannelErrCode())
+                .setChannelErrorMsg(respBO.getChannelErrMsg());
+        updatePayRefund(updateRefundDO);
+
+        PayOrderDO updateOrderDO = new PayOrderDO();
+        //更新订单表
+        updateOrderDO.setId(respBO.getOrderId())
+                .setRefundTimes(respBO.getRefundedTimes() + 1);
+        updatePayOrder(updateOrderDO);
+
+        //TODO 发起重试任务
+    }
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelSuccessHandler.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundChannelSuccessHandler.java
@ -0,0 +1,64 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.impl;
+
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayOrderCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayRefundMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.notify.PayNotifyTypeEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.service.notify.PayNotifyCoreService;
+import cn.iocoder.yudao.coreservice.modules.pay.service.notify.dto.PayNotifyTaskCreateReqDTO;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.PayRefundAbstractChannelPostHandler;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundPostReqBO;
+import cn.iocoder.yudao.framework.pay.core.enums.PayChannelRespEnum;
+import org.springframework.stereotype.Service;
+
+import javax.annotation.Resource;
+import java.util.Date;
+/**
+ * 支付退款订单渠道返回退款成功的后置处理类
+ * {@link PayChannelRespEnum#SYNC_SUCCESS}
+ */
+@Service
+public class PayRefundChannelSuccessHandler extends PayRefundAbstractChannelPostHandler {
+
+
+    @Resource
+    private PayNotifyCoreService payNotifyCoreService;
+
+
+    public PayRefundChannelSuccessHandler(PayOrderCoreMapper payOrderCoreMapper,
+                                          PayRefundMapper payRefundMapper) {
+        super(payOrderCoreMapper, payRefundMapper);
+    }
+
+    @Override
+    public PayChannelRespEnum[] supportHandleResp() {
+        return new PayChannelRespEnum[]{PayChannelRespEnum.SYNC_SUCCESS};
+    }
+
+    @Override
+    public void handleRefundChannelResp(PayRefundPostReqBO respBO) {
+        //退款成功
+        PayRefundDO updateRefundDO = new PayRefundDO();
+        //更新退款单表
+        updateRefundDO.setId(respBO.getRefundId())
+                .setStatus(PayRefundStatusEnum.SUCCESS.getStatus())
+                .setChannelRefundNo(respBO.getChannelRefundNo())
+                .setSuccessTime(new Date());
+        updatePayRefund(updateRefundDO);
+
+        PayOrderDO updateOrderDO = new PayOrderDO();
+        //更新订单表
+        updateOrderDO.setId(respBO.getOrderId())
+                .setRefundTimes(respBO.getRefundedTimes() + 1)
+                .setRefundStatus(respBO.getRefundTypeEnum().getStatus())
+                .setRefundAmount(respBO.getRefundedAmount()+respBO.getRefundAmount());
+         updatePayOrder(updateOrderDO);
+
+         // 立刻插入退款通知记录
+        // TODO 通知商户成功或者失败. 现在通知似乎没有实现， 只是回调
+        payNotifyCoreService.createPayNotifyTask(PayNotifyTaskCreateReqDTO.builder()
+                .type(PayNotifyTypeEnum.REFUND.getType()).dataId(respBO.getRefundId()).build());
+    }
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundCoreServiceImpl.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/service/order/impl/PayRefundCoreServiceImpl.java
@ -0,0 +1,203 @@
+package cn.iocoder.yudao.coreservice.modules.pay.service.order.impl;
+
+import cn.hutool.core.util.StrUtil;
+import cn.iocoder.yudao.coreservice.modules.pay.convert.order.PayRefundCoreConvert;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.merchant.PayAppDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.merchant.PayChannelDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayOrderExtensionDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.dataobject.order.PayRefundDO;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayOrderCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayOrderExtensionCoreMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.dal.mysql.order.PayRefundMapper;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayOrderNotifyStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundTypeEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayOrderStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.enums.order.PayRefundStatusEnum;
+import cn.iocoder.yudao.coreservice.modules.pay.service.merchant.PayAppCoreService;
+import cn.iocoder.yudao.coreservice.modules.pay.service.merchant.PayChannelCoreService;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.PayRefundCoreService;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.PayRefundChannelPostHandler;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundPostReqBO;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundReqBO;
+import cn.iocoder.yudao.coreservice.modules.pay.service.order.bo.PayRefundRespBO;
+import cn.iocoder.yudao.coreservice.modules.pay.util.PaySeqUtils;
+import cn.iocoder.yudao.framework.pay.core.client.PayClient;
+import cn.iocoder.yudao.framework.pay.core.client.PayClientFactory;
+import cn.iocoder.yudao.framework.pay.core.client.dto.PayRefundUnifiedReqDTO;
+import cn.iocoder.yudao.framework.pay.core.client.dto.PayRefundUnifiedRespDTO;
+import cn.iocoder.yudao.framework.pay.core.enums.PayChannelRespEnum;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import javax.annotation.PostConstruct;
+import javax.annotation.Resource;
+import java.util.*;
+
+import static cn.iocoder.yudao.coreservice.modules.pay.enums.PayErrorCodeCoreConstants.*;
+import static cn.iocoder.yudao.framework.common.exception.util.ServiceExceptionUtil.exception;
+
+@Service
+@Slf4j
+public class PayRefundCoreServiceImpl implements PayRefundCoreService {
+
+    @Resource
+    private PayOrderCoreMapper payOrderCoreMapper;
+
+    @Resource
+    private PayRefundMapper payRefundMapper;
+
+    @Resource
+    private PayOrderExtensionCoreMapper payOrderExtensionCoreMapper;
+
+    @Resource
+    private PayAppCoreService payAppCoreService;
+
+    @Resource
+    private PayChannelCoreService payChannelCoreService;
+
+    @Resource
+    private PayClientFactory payClientFactory;
+
+    /**
+     * 处理渠道返回结果的后置处理器 集合
+     */
+    @Resource
+    private List<PayRefundChannelPostHandler> handlerList;
+
+
+    private final EnumMap<PayChannelRespEnum, PayRefundChannelPostHandler> mapHandler = new EnumMap<>(PayChannelRespEnum.class);
+
+
+
+    @PostConstruct
+    public void init(){
+
+        if (Objects.nonNull(handlerList)) {
+            handlerList.forEach(t->{
+                for (PayChannelRespEnum item : t.supportHandleResp()) {
+                    mapHandler.put(item, t);
+                }
+            });
+        }
+
+    }
+
+
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public PayRefundRespBO refund(PayRefundReqBO reqBO) {
+        // 获得 PayOrderDO
+        PayOrderDO order = payOrderCoreMapper.selectById(reqBO.getPayOrderId());
+        // 校验订单是否存在
+        if (Objects.isNull(order) ) {
+            throw exception(PAY_ORDER_NOT_FOUND);
+        }
+        // 校验 App
+        PayAppDO app = payAppCoreService.validPayApp(order.getAppId());
+        // 校验支付渠道是否有效
+        PayChannelDO channel = payChannelCoreService.validPayChannel(order.getChannelId());
+        // 校验支付客户端是否正确初始化
+        PayClient client = payClientFactory.getPayClient(channel.getId());
+        if (client == null) {
+            log.error("[refund][渠道编号({}) 找不到对应的支付客户端]", channel.getId());
+            throw exception(PAY_CHANNEL_CLIENT_NOT_FOUND);
+        }
+
+        //校验退款的条件
+        validatePayRefund(reqBO, order);
+
+        //退款类型
+        PayRefundTypeEnum refundType = PayRefundTypeEnum.SOME;
+        if (Objects.equals(reqBO.getAmount(), order.getAmount())) {
+            refundType = PayRefundTypeEnum.ALL;
+        }
+
+        //退款单入库 退款单状态：生成,  没有和渠道产生交互
+        PayOrderExtensionDO orderExtensionDO = payOrderExtensionCoreMapper.selectById(order.getSuccessExtensionId());
+        PayRefundDO refundDO = PayRefundDO.builder().channelOrderNo(order.getChannelOrderNo())
+                .appId(order.getAppId())
+                .channelOrderNo(order.getChannelOrderNo())
+                .channelCode(order.getChannelCode())
+                .channelId(order.getChannelId())
+                .merchantId(order.getMerchantId())
+                .orderId(order.getId())
+                .merchantRefundNo(reqBO.getMerchantRefundNo())
+                .notifyUrl(app.getRefundNotifyUrl())
+                .payAmount(order.getAmount())
+                .refundAmount(reqBO.getAmount())
+                .userIp(reqBO.getUserIp())
+                .merchantOrderId(order.getMerchantOrderId())
+                .tradeNo(orderExtensionDO.getNo())
+                .status(PayRefundStatusEnum.CREATE.getStatus())
+                .reason(reqBO.getReason())
+                .notifyStatus(PayOrderNotifyStatusEnum.NO.getStatus())
+                .reqNo(PaySeqUtils.genRefundReqNo())
+                .type(refundType.getStatus())
+                .build();
+
+         payRefundMapper.insert(refundDO);
+
+         PayRefundUnifiedReqDTO unifiedReqDTO = PayRefundUnifiedReqDTO.builder()
+                .userIp(reqBO.getUserIp())
+                .channelOrderNo(refundDO.getChannelOrderNo())
+                .payTradeNo(refundDO.getTradeNo())
+                .refundReqNo(refundDO.getReqNo())
+                .amount(reqBO.getAmount())
+                .reason(refundDO.getReason())
+                .build();
+
+         //调用渠道进行退款
+         PayRefundUnifiedRespDTO refundUnifiedRespDTO = client.unifiedRefund(unifiedReqDTO);
+
+        //根据渠道返回，获取退款后置处理，由postHandler 进行处理
+         PayRefundChannelPostHandler payRefundChannelPostHandler = mapHandler.get(refundUnifiedRespDTO.getRespEnum());
+
+         if(Objects.isNull(payRefundChannelPostHandler)){
+             throw exception(PAY_REFUND_POST_HANDLER_NOT_FOUND);
+         }
+
+         PayRefundPostReqBO bo = PayRefundCoreConvert.INSTANCE.convert(refundUnifiedRespDTO);
+         bo.setRefundAmount(reqBO.getAmount())
+            .setRefundedAmount(order.getRefundAmount())
+            .setRefundedTimes(order.getRefundTimes())
+            .setRefundId(refundDO.getId())
+            .setOrderId(order.getId())
+            .setRefundTypeEnum(refundType);
+
+         //调用退款的后置处理
+         payRefundChannelPostHandler.handleRefundChannelResp(bo);
+
+         return PayRefundRespBO.builder().refundId(refundDO.getId()).build();
+    }
+
+
+    /**
+     * 校验是否进行退款
+     * @param reqBO 退款申请信息
+     * @param order 原始支付订单信息
+     */
+    private void validatePayRefund(PayRefundReqBO reqBO, PayOrderDO order) {
+
+        // 校验状态，必须是支付状态
+        if (!PayOrderStatusEnum.SUCCESS.getStatus().equals(order.getStatus())) {
+            throw exception(PAY_ORDER_STATUS_IS_NOT_SUCCESS);
+        }
+        //是否已经全额退款
+        if (PayRefundTypeEnum.ALL.getStatus().equals(order.getRefundStatus())) {
+            throw exception(PAY_REFUND_ALL_REFUNDED);
+        }
+        // 校验金额 退款金额不能大于 原定的金额
+        if(reqBO.getAmount() + order.getRefundAmount() > order.getAmount()){
+            throw exception(PAY_REFUND_AMOUNT_EXCEED);
+        }
+        //校验渠道订单号
+        if (StrUtil.isEmpty(order.getChannelOrderNo())) {
+            throw exception(PAY_REFUND_CHN_ORDER_NO_IS_NULL);
+        }
+        //TODO  退款的期限  退款次数的控制
+
+
+    }
+}
--- a/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/util/PaySeqUtils.java
+++ b/yudao-core-service/src/main/java/cn/iocoder/yudao/coreservice/modules/pay/util/PaySeqUtils.java
@ -0,0 +1,50 @@
+package cn.iocoder.yudao.coreservice.modules.pay.util;
+
+import cn.hutool.core.date.DatePattern;
+import cn.hutool.core.date.DateUtil;
+import cn.hutool.core.util.RandomUtil;
+
+import java.util.Date;
+import java.util.concurrent.atomic.AtomicLong;
+
+/**
+ * 支付相关编号的生产
+ */
+public class PaySeqUtils {
+
+    private static final AtomicLong REFUND_REQ_NO_SEQ = new AtomicLong(0L);
+
+    private static final AtomicLong MER_REFUND_NO_SEQ = new AtomicLong(0L);
+
+    private static final AtomicLong MER_ORDER_NO_SEQ = new AtomicLong(0L);
+
+    /**
+     * 生成商户退款单号，用于测试，应该由商户系统生成
+     * @return 商户退款单
+     */
+    public static String genMerchantRefundNo() {
+        return String.format("%s%s%04d", "MR",
+                DateUtil.format(new Date(), DatePattern.PURE_DATETIME_MS_PATTERN),
+                (int) MER_REFUND_NO_SEQ.getAndIncrement() % 10000);
+    }
+
+    /**
+     * 生成退款请求号
+     * @return 退款请求号
+     */
+    public static String genRefundReqNo() {
+        return String.format("%s%s%04d", "RR",
+                DateUtil.format(new Date(), DatePattern.PURE_DATETIME_MS_PATTERN),
+                (int) REFUND_REQ_NO_SEQ.getAndIncrement() % 10000);
+    }
+
+    /**
+     * 生成商户订单编号号 用于测试，应该由商户系统生成
+     * @return 商户订单编号
+     */
+    public static String genMerchantOrderNo() {
+        return String.format("%s%s%04d", "MO",
+                DateUtil.format(new Date(), DatePattern.PURE_DATETIME_MS_PATTERN),
+                (int) MER_ORDER_NO_SEQ.getAndIncrement() % 10000);
+    }
+}