Introduce `IOrderAppService.CheckCreateAsync` method

modules/EasyAbp.EShop.Orders/src/EasyAbp.EShop.Orders.Application.Contracts/EasyAbp/EShop/Orders/Orders/Dtos/CheckCreateOrderInput.cs

@@ -0,0 +1,8 @@
+using System;
+
+namespace EasyAbp.EShop.Orders.Orders.Dtos;
+
+[Serializable]
+public class CheckCreateOrderInput : CreateOrderDto
+{
+}

modules/EasyAbp.EShop.Orders/src/EasyAbp.EShop.Orders.Application.Contracts/EasyAbp/EShop/Orders/Orders/Dtos/CheckCreateOrderResultDto.cs

@@ -0,0 +1,11 @@
+using System;
+
+namespace EasyAbp.EShop.Orders.Orders.Dtos;
+
+[Serializable]
+public class CheckCreateOrderResultDto
+{
+    public bool CanCreate { get; set; }
+    
+    public string Reason { get; set; }
+}

modules/EasyAbp.EShop.Orders/src/EasyAbp.EShop.Orders.Application.Contracts/EasyAbp/EShop/Orders/Orders/IOrderAppService.cs

@@ -19,5 +19,7 @@ namespace EasyAbp.EShop.Orders.Orders
         Task<OrderDto> CancelAsync(Guid id, CancelOrderInput input);
 
         Task<OrderDto> UpdateStaffRemarkAsync(Guid id, UpdateStaffRemarkInput input);
+
+        Task<CheckCreateOrderResultDto> CheckCreateAsync(CheckCreateOrderInput input);
     }
 }

modules/EasyAbp.EShop.Orders/src/EasyAbp.EShop.Orders.Application/EasyAbp/EShop/Orders/Orders/OrderAppService.cs

@@ -12,6 +12,7 @@ using EasyAbp.EShop.Stores.Stores;
 using Microsoft.AspNetCore.Authorization;
 using Volo.Abp;
 using Volo.Abp.Application.Dtos;
+using Volo.Abp.Uow;
 using Volo.Abp.Users;
 
 namespace EasyAbp.EShop.Orders.Orders
@@ -91,7 +92,7 @@ namespace EasyAbp.EShop.Orders.Orders
             var productDict = await GetProductDictionaryAsync(input.OrderLines.Select(dto => dto.ProductId).ToList());
 
             ThrowIfExistFlashSalesProduct(productDict);
-            
+
             await AuthorizationService.CheckAsync(
                 new OrderCreationResource
                 {
@@ -108,11 +109,12 @@ namespace EasyAbp.EShop.Orders.Orders
                 .Where(x => x.HasValue)
                 .Select(x => x.Value)
                 .ToList();
-            
+
             var productDetailDict = await GetProductDetailDictionaryAsync(productDetailIds);
 
             // Todo: Can we use IProductDataScopedCache/IProductDetailDataScopedCache instead of productDict/productDetailDict?
-            var order = await _newOrderGenerator.GenerateAsync(CurrentUser.GetId(), input, productDict, productDetailDict);
+            var order = await _newOrderGenerator.GenerateAsync(CurrentUser.GetId(), input, productDict,
+                productDetailDict);
 
             await DiscountOrderAsync(order, productDict);
 
@@ -203,11 +205,11 @@ namespace EasyAbp.EShop.Orders.Orders
 
             return await MapToGetOutputDtoAsync(order);
         }
-        
+
         public virtual async Task<OrderDto> CancelAsync(Guid id, CancelOrderInput input)
         {
             var order = await GetEntityByIdAsync(id);
-            
+
             await AuthorizationService.CheckAsync(
                 order,
                 new OrderOperationAuthorizationRequirement(OrderOperation.Cancellation)
@@ -225,10 +227,39 @@ namespace EasyAbp.EShop.Orders.Orders
             await CheckMultiStorePolicyAsync(order.StoreId, OrdersPermissions.Orders.Manage);
 
             order.SetStaffRemark(input.StaffRemark);
-            
+
             await Repository.UpdateAsync(order, true);
 
             return await MapToGetOutputDtoAsync(order);
         }
+
+        public virtual async Task<CheckCreateOrderResultDto> CheckCreateAsync(CheckCreateOrderInput input)
+        {
+            var requiresNewUow = !UnitOfWorkManager.Current?.Options.IsTransactional ?? false;
+            using var uow = UnitOfWorkManager.Begin(new AbpUnitOfWorkOptions(true), requiresNewUow);
+
+            try
+            {
+                await CreateAsync(input);
+
+                await uow.RollbackAsync();
+            }
+            catch
+            {
+                await uow.RollbackAsync();
+
+                return new CheckCreateOrderResultDto
+                {
+                    CanCreate = false,
+                    Reason = "Unknown" // Todo: get failure reason
+                };
+            }
+
+            return new CheckCreateOrderResultDto
+            {
+                CanCreate = true,
+                Reason = null,
+            };
+        }
     }
 }

modules/EasyAbp.EShop.Orders/src/EasyAbp.EShop.Orders.HttpApi/EasyAbp/EShop/Orders/Orders/OrderController.cs

@@ -81,5 +81,12 @@ namespace EasyAbp.EShop.Orders.Orders
         {
             return _service.UpdateStaffRemarkAsync(id, input);
         }
+
+        [HttpPost]
+        [Route("check-create")]
+        public virtual Task<CheckCreateOrderResultDto> CheckCreateAsync(CheckCreateOrderInput input)
+        {
+            return _service.CheckCreateAsync(input);
+        }
     }
 }

modules/EasyAbp.EShop.Orders/test/EasyAbp.EShop.Orders.Application.Tests/Orders/OrderAppServiceTests.cs

@@ -13,6 +13,7 @@ using Microsoft.Extensions.DependencyInjection;
 using NSubstitute;
 using Shouldly;
 using Volo.Abp;
+using Volo.Abp.Domain.Repositories;
 using Volo.Abp.Settings;
 using Volo.Abp.Timing;
 using Xunit;
@@ -113,6 +114,88 @@ namespace EasyAbp.EShop.Orders.Orders
             services.AddTransient(_ => productDetailAppService);
         }
 
+        [Fact]
+        public async Task Check_Create_Order_Should_Succeed()
+        {
+            var orderRepository = ServiceProvider.GetRequiredService<IOrderRepository>();
+            var orderCount = 0;
+            await WithUnitOfWorkAsync(async () =>
+            {
+                orderCount = await orderRepository.CountAsync();
+            });
+
+            // Arrange
+            var checkCreateOrderInput = new CheckCreateOrderInput
+            {
+                CustomerRemark = "customer remark",
+                StoreId = OrderTestData.Store1Id,
+                OrderLines = new List<CreateOrderLineDto>
+                {
+                    new CreateOrderLineDto
+                    {
+                        ProductId = OrderTestData.Product1Id,
+                        ProductSkuId = OrderTestData.ProductSku1Id,
+                        Quantity = 10
+                    }
+                }
+            };
+
+            CheckCreateOrderResultDto resultDto = null;
+            // Act
+            await WithUnitOfWorkAsync(async () =>
+            {
+                resultDto = await _orderAppService.CheckCreateAsync(checkCreateOrderInput);
+            });
+
+            // Assert
+            resultDto.CanCreate.ShouldBeTrue();
+            await WithUnitOfWorkAsync(async () =>
+            {
+                orderCount.ShouldBeEquivalentTo(await orderRepository.CountAsync());
+            });
+        }
+
+        [Fact]
+        public async Task Check_Create_Order_Should_Fail()
+        {
+            var orderRepository = ServiceProvider.GetRequiredService<IOrderRepository>();
+            var orderCount = 0;
+            await WithUnitOfWorkAsync(async () =>
+            {
+                orderCount = await orderRepository.CountAsync();
+            });
+
+            // Arrange
+            var checkCreateOrderInput = new CheckCreateOrderInput
+            {
+                CustomerRemark = "customer remark",
+                StoreId = OrderTestData.Store1Id,
+                OrderLines = new List<CreateOrderLineDto>
+                {
+                    new CreateOrderLineDto
+                    {
+                        ProductId = OrderTestData.Product1Id,
+                        ProductSkuId = OrderTestData.ProductSku1Id,
+                        Quantity = 101 // limited range: 1-100
+                    }
+                }
+            };
+
+            CheckCreateOrderResultDto resultDto = null;
+            // Act
+            await WithUnitOfWorkAsync(async () =>
+            {
+                resultDto = await _orderAppService.CheckCreateAsync(checkCreateOrderInput);
+            });
+
+            // Assert
+            resultDto.CanCreate.ShouldBeFalse();
+            await WithUnitOfWorkAsync(async () =>
+            {
+                orderCount.ShouldBeEquivalentTo(await orderRepository.CountAsync());
+            });
+        }
+
         [Fact]
         public async Task Order_Should_Be_Created()
         {