feat: update GetOrderByIdQuery to allow nullable UserId and adjust query handling in GetOrderByIdQueryHandler

src/CMSMicroservice.Application/DiscountShopCQ/Queries/GetOrderById/GetOrderByIdQuery.cs

@@ -6,7 +6,7 @@ namespace CMSMicroservice.Application.DiscountShopCQ.Queries.GetOrderById;
 public class GetOrderByIdQuery : IRequest<OrderDetailDto?>
 {
     public long OrderId { get; set; }
-    public long UserId { get; set; }
+    public long? UserId { get; set; }
 }
 
 public class OrderDetailDto

src/CMSMicroservice.Application/DiscountShopCQ/Queries/GetOrderById/GetOrderByIdQueryHandler.cs

@@ -15,8 +15,15 @@ public class GetOrderByIdQueryHandler : IRequestHandler<GetOrderByIdQuery, Order
 
     public async Task<OrderDetailDto?> Handle(GetOrderByIdQuery request, CancellationToken cancellationToken)
     {
-        var order = await _context.DiscountOrders
-            .Where(o => o.Id == request.OrderId && o.UserId == request.UserId)
+        var query = _context.DiscountOrders
+            .Where(o => o.Id == request.OrderId);
+
+        if (request.UserId.HasValue && request.UserId.Value > 0)
+        {
+            query = query.Where(o => o.UserId == request.UserId.Value);
+        }
+
+        var order = await query
             .Include(o => o.UserAddress)
             .Include(o => o.OrderDetails)
                 .ThenInclude(od => od.Product)

src/CMSMicroservice.WebApi/Services/DiscountOrderService.cs

@@ -86,10 +86,15 @@ public class DiscountOrderService : DiscountOrderContract.DiscountOrderContractB
 
     public override async Task<GetOrderByIdResponse> GetOrderById(GetOrderByIdRequest request, ServerCallContext context)
     {
+        var currentUserId = GetCurrentUserId();
+        long? filterUserId = request.UserId > 0
+            ? request.UserId
+            : (currentUserId > 0 ? currentUserId : null);
+
         var query = new GetOrderByIdQuery
         {
             OrderId = request.OrderId,
-            UserId = GetCurrentUserId()
+            UserId = filterUserId
         };
         var result = await _sender.Send(query);
         if (result == null)