领取优惠券开启事务，并在查询优惠券信息时加update锁解决并发领优惠券产生超买问题。

修复优惠券领取数量设置为0时，没有返回错误

CoreCms.Net.IRepository/IBaseRepository.cs

@@ -203,8 +203,11 @@ namespace CoreCms.Net.IRepository
         /// </summary>
         /// <param name="predicate">条件表达式树</param>
         /// <param name="blUseNoLock">是否使用WITH(NOLOCK)</param>
+        /// <param name="blUseTranLock">是否使用事务锁</param>
+        /// <param name="dbLockType">事务锁类型</param>
         /// <returns></returns>
-        Task<T> QueryByClauseAsync(Expression<Func<T, bool>> predicate, bool blUseNoLock = false);
+        Task<T> QueryByClauseAsync(Expression<Func<T, bool>> predicate, bool blUseNoLock = false,bool blUseTranLock = false,
+            DbLockType dbLockType = DbLockType.Wait);
 
         /// <summary>
         ///     根据条件查询数据

CoreCms.Net.Repository/BaseRepository.cs

@@ -331,12 +331,16 @@ namespace CoreCms.Net.Repository
         /// </summary>
         /// <param name="predicate">条件表达式树</param>
         /// <param name="blUseNoLock">是否使用WITH(NOLOCK)</param>
+        /// <param name="blUseTranLock">是否使用事务锁</param>
+        /// <param name="dbLockType">事务锁类型</param>
         /// <returns></returns>
-        public async Task<T> QueryByClauseAsync(Expression<Func<T, bool>> predicate, bool blUseNoLock = false)
+        public async Task<T> QueryByClauseAsync(Expression<Func<T, bool>> predicate, bool blUseNoLock = false,bool blUseTranLock = false,
+            DbLockType dbLockType = DbLockType.Wait)
         {
             return blUseNoLock
                 ? await DbBaseClient.Queryable<T>().With(SqlWith.NoLock).FirstAsync(predicate)
-                : await DbBaseClient.Queryable<T>().FirstAsync(predicate);
+                : (blUseTranLock? await DbBaseClient.Queryable<T>().TranLock(dbLockType).FirstAsync(predicate)
+                    : await DbBaseClient.Queryable<T>().FirstAsync(predicate));
         }
 
         /// <summary>

CoreCms.Net.Services/Promotion/CoreCmsPromotionServices.cs

@@ -465,16 +465,17 @@ namespace CoreCms.Net.Services
             where = where.And(p => p.isDel == false);  //是否被删除
 
 
-            var info = await _dal.QueryByClauseAsync(where);
+            var info = await _dal.QueryByClauseAsync(where,false,true);
             if (info != null)
             {
                 jm.data = info;
                 //判断最大领取数量
                 if (info.maxRecevieNums == 0)
                 {
-                    jm.status = true;
+                    jm.status = false;
                     return jm;
                 }
+                
                 var receiveCount = await _couponServices.GetCountAsync(p => p.promotionId == promotionId);
                 if (receiveCount >= info.maxRecevieNums)
                 {

CoreCms.Net.Web.WebApi/Controllers/CouponController.cs

@@ -13,6 +13,7 @@ using System.Linq;
 using System.Threading.Tasks;
 using CoreCms.Net.Auth.HttpContextUser;
 using CoreCms.Net.Configuration;
+using CoreCms.Net.IRepository.UnitOfWork;
 using CoreCms.Net.IServices;
 using CoreCms.Net.Model.Entities;
 using CoreCms.Net.Model.FromBody;
@@ -33,18 +34,21 @@ namespace CoreCms.Net.Web.WebApi.Controllers
         private readonly IHttpContextUser _user;
         private readonly ICoreCmsCouponServices _couponServices;
         private readonly ICoreCmsPromotionServices _promotionServices;
+        private readonly IUnitOfWork _unionOfWork;
         /// <summary>
         /// 构造函数
         /// </summary>
         /// <param name="user"></param>
         /// <param name="couponServices"></param>
         /// <param name="promotionServices"></param>
+        /// <param name="unionOfWork"></param>
         public CouponController(IHttpContextUser user
-            , ICoreCmsCouponServices couponServices, ICoreCmsPromotionServices promotionServices)
+            , ICoreCmsCouponServices couponServices, ICoreCmsPromotionServices promotionServices, IUnitOfWork unionOfWork)
         {
             _user = user;
             _couponServices = couponServices;
             _promotionServices = promotionServices;
+            _unionOfWork = unionOfWork;
         }
 
         //公共接口====================================================================================================
@@ -144,32 +148,55 @@ namespace CoreCms.Net.Web.WebApi.Controllers
                 jm.msg = GlobalErrorCodeVars.Code15006;
                 return jm;
             }
-            //判断优惠券是否可以领取?
-            var promotionModel = await _promotionServices.ReceiveCoupon(entity.id);
-            if (promotionModel.status == false)
+            
+            try
             {
-                return promotionModel;
-            }
+                _unionOfWork.BeginTran();
 
-            var promotion = (CoreCmsPromotion)promotionModel.data;
-            if (promotion == null)
-            {
-                jm.msg = GlobalErrorCodeVars.Code15019;
-                return jm;
-            }
 
-            if (promotion.maxNums > 0)
-            {
-                //判断用户是否已领取?领取次数
-                var couponResult = await _couponServices.GetMyCoupon(_user.ID, entity.id, "all", 1, 9999);
-                if (couponResult.status && couponResult.code >= promotion.maxNums)
+                //判断优惠券是否可以领取?
+                var promotionModel = await _promotionServices.ReceiveCoupon(entity.id);
+                if (promotionModel.status == false)
                 {
-                    jm.msg = GlobalErrorCodeVars.Code15018;
+                    _unionOfWork.RollbackTran();
+                    return promotionModel;
+                }
+
+                
+                
+                var promotion = (CoreCmsPromotion)promotionModel.data;
+                if (promotion == null)
+                {
+                    _unionOfWork.RollbackTran();
+                    jm.msg = GlobalErrorCodeVars.Code15019;
                     return jm;
                 }
+
+                if (promotion.maxNums > 0)
+                {
+                    //判断用户是否已领取?领取次数
+                    var couponResult = await _couponServices.GetMyCoupon(_user.ID, entity.id, "all", 1, 9999);
+                    if (couponResult.status && couponResult.code >= promotion.maxNums)
+                    {
+                        _unionOfWork.RollbackTran();
+                        jm.msg = GlobalErrorCodeVars.Code15018;
+                        return jm;
+                    }
+                }
+                
+                jm = await _couponServices.AddData(_user.ID, entity.id, promotion);
+
+                _unionOfWork.CommitTran();
+
+                jm.otherData = promotionModel;
+
+            }
+            catch (Exception e)
+            {
+                _unionOfWork.RollbackTran();
+                jm.msg = GlobalErrorCodeVars.Code10000;
             }
-            jm = await _couponServices.AddData(_user.ID, entity.id, promotion);
-            jm.otherData = promotionModel;
+            
             return jm;
         }
         #endregion