MyOrders.cs

using System;
using MediatR;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Microsoft.eShopWeb.Infrastructure.Data;

namespace Microsoft.eShopWeb.Web.Features.MyOrders
{   
    public class MyOrdersViewModel
    {
        public IEnumerable<OrderSummaryViewModel> Orders { get; set; }
    }
    
    public class OrderSummaryViewModel
    {
        private const string DEFAULT_STATUS = "Pending";

        public int OrderNumber { get; set; }
        public DateTimeOffset OrderDate { get; set; }
        public decimal Total { get; set; }
        public string Status => DEFAULT_STATUS;
    }
    
    public class GetMyOrdersHandler : IRequestHandler<GetMyOrders, MyOrdersViewModel>
    {
        private readonly CatalogContext _db;

        public GetMyOrdersHandler(CatalogContext db)
        {
            _db = db;
        }

        public async Task<MyOrdersViewModel> Handle(GetMyOrders request, CancellationToken cancellationToken)
        {
            var result = new MyOrdersViewModel();
            result.Orders = await _db.Orders
                .Include(x => x.OrderItems)
                .Where(x => x.BuyerId == request.UserName)
                .Select(o => new OrderSummaryViewModel
                {
                    OrderDate = o.OrderDate,
                    OrderNumber = o.Id,
                    Total = o.OrderItems.Sum(x => x.Units * x.UnitPrice),
                })
                .ToArrayAsync(cancellationToken: cancellationToken);
            
            return result;
        }
    }
}