Add appKey to PayAppDO and update PayOrderApi to use appKey

---

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yudao-module-pay/yudao-module-pay-api/src/main/java/cn/iocoder/yudao/module/pay/api/order/dto/PayOrderCreateReqDTO.java

@@ -18,10 +18,10 @@ public class PayOrderCreateReqDTO implements Serializable {
     public static final int SUBJECT_MAX_LENGTH = 32;
 
     /**
-     * 应用编号
+     * 应用密钥
      */
-    @NotNull(message = "应用编号不能为空")
-    private Long appId;
+    @NotEmpty(message = "应用密钥不能为空")
+    private String appKey;
     /**
      * 用户 IP
      */

yudao-module-pay/yudao-module-pay-api/src/main/java/cn/iocoder/yudao/module/pay/api/order/dto/PayOrderRespDTO.java

@@ -43,4 +43,9 @@ public class PayOrderRespDTO {
 
     // ========== 渠道相关字段 ==========
 
+    /**
+     * 应用密钥
+     */
+    private String appKey;
+
 }

yudao-module-pay/yudao-module-pay-biz/src/main/java/cn/iocoder/yudao/module/pay/dal/dataobject/app/PayAppDO.java

@@ -59,4 +59,9 @@ public class PayAppDO extends BaseDO {
      */
     private String transferNotifyUrl;
 
+    /**
+     * 应用密钥
+     */
+    private String appKey;
+
 }

yudao-module-pay/yudao-module-pay-biz/src/main/java/cn/iocoder/yudao/module/pay/service/order/PayOrderServiceImpl.java

@@ -111,11 +111,11 @@ public class PayOrderServiceImpl implements PayOrderService {
     @Override
     public Long createOrder(PayOrderCreateReqDTO reqDTO) {
         // 校验 App
-        PayAppDO app = appService.validPayApp(reqDTO.getAppId());
+        PayAppDO app = appService.validPayApp(reqDTO.getAppKey());
 
         // 查询对应的支付交易单是否已经存在。如果是，则直接返回
         PayOrderDO order = orderMapper.selectByAppIdAndMerchantOrderId(
-                reqDTO.getAppId(), reqDTO.getMerchantOrderId());
+                app.getId(), reqDTO.getMerchantOrderId());
         if (order != null) {
             log.warn("[createOrder][appId({}) merchantOrderId({}) 已经存在对应的支付单({})]", order.getAppId(),
                     order.getMerchantOrderId(), toJsonString(order)); // 理论来说，不会出现这个情况