Refactor to eliminate unneeded BasketQueryService

src/ApplicationCore/Entities/BasketAggregate/Basket.cs

@@ -10,6 +10,9 @@ public class Basket : BaseEntity, IAggregateRoot
     private readonly List<BasketItem> _items = new List<BasketItem>();
     public IReadOnlyCollection<BasketItem> Items => _items.AsReadOnly();
 
+    public int TotalItems => _items.Sum(i => i.Quantity);
+
+
     public Basket(string buyerId)
     {
         BuyerId = buyerId;

src/ApplicationCore/Interfaces/IBasketQueryService.cs

@@ -1,8 +0,0 @@
-using System.Threading.Tasks;
-
-namespace Microsoft.eShopWeb.ApplicationCore.Interfaces;
-
-public interface IBasketQueryService
-{
-    Task<int> CountTotalBasketItems(string username);
-}

src/Infrastructure/Data/BasketQueryService.cs

@@ -1,26 +0,0 @@
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.eShopWeb.ApplicationCore.Interfaces;
-
-namespace Microsoft.eShopWeb.Infrastructure.Data;
-
-public class BasketQueryService : IBasketQueryService
-{
-    private readonly CatalogContext _dbContext;
-
-    public BasketQueryService(CatalogContext dbContext)
-    {
-        _dbContext = dbContext;
-    }
-
-    public async Task<int> CountTotalBasketItems(string username)
-    {
-        var totalItems = await _dbContext.Baskets
-            .Where(basket => basket.BuyerId == username)
-            .SelectMany(item => item.Items)
-            .SumAsync(sum => sum.Quantity);
-
-        return totalItems;
-    }
-}

src/Web/Configuration/ConfigureCoreServices.cs

@@ -18,7 +18,6 @@ public static class ConfigureCoreServices
 
         services.AddScoped<IBasketService, BasketService>();
         services.AddScoped<IOrderService, OrderService>();
-        services.AddScoped<IBasketQueryService, BasketQueryService>();
         services.AddSingleton<IUriComposer>(new UriComposer(configuration.Get<CatalogSettings>()));
         services.AddScoped(typeof(IAppLogger<>), typeof(LoggerAdapter<>));
         services.AddTransient<IEmailSender, EmailSender>();

src/Web/Interfaces/IBasketViewModelService.cs

@@ -7,8 +7,5 @@ namespace Microsoft.eShopWeb.Web.Interfaces;
 public interface IBasketViewModelService
 {
     Task<BasketViewModel> GetOrCreateBasketForUser(string userName);
-
-    Task<int> CountTotalBasketItems(string username);
-
     Task<BasketViewModel> Map(Basket basket);
 }

src/Web/Pages/Basket/Checkout.cshtml

@@ -80,7 +80,7 @@
         </h3>
 
         <section class="esh-basket-item">
-            <a asp-page="/Index" class="btn esh-basket-checkout text-white">[ Continue Shopping..]</a>
+            <a asp-page="/Index" class="btn esh-basket-checkout text-white">[ Continue Shopping ]</a>
         </section>
     }
 </div>

src/Web/Pages/Basket/Index.cshtml

@@ -63,7 +63,7 @@
                 </div>
                 <div class="row">
                     <section class="esh-basket-item col-xs-1">
-                        <a asp-page="/Index" class="btn esh-basket-checkout text-white">[ Continue Shopping..]</a>
+                        <a asp-page="/Index" class="btn esh-basket-checkout text-white">[ Continue Shopping ]</a>
                     </section>
                     <section class="esh-basket-item col-xs-push-7 col-xs-4">
 
@@ -84,7 +84,7 @@
         </h3>
 
         <section class="esh-basket-item">
-            <a asp-page="/Index" class="btn esh-basket-checkout text-white">[ Continue Shopping..]</a>
+            <a asp-page="/Index" class="btn esh-basket-checkout text-white">[ Continue Shopping ]</a>
         </section>
     }
 </div>

src/Web/Pages/Shared/Components/BasketComponent/Basket.cs

@@ -2,21 +2,27 @@
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.eShopWeb.ApplicationCore.Interfaces;
+using Microsoft.eShopWeb.ApplicationCore.Specifications;
 using Microsoft.eShopWeb.Infrastructure.Identity;
 using Microsoft.eShopWeb.Web.Interfaces;
 using Microsoft.eShopWeb.Web.ViewModels;
+using BasketEntity = Microsoft.eShopWeb.ApplicationCore.Entities.BasketAggregate.Basket;
 
 namespace Microsoft.eShopWeb.Web.Pages.Shared.Components.BasketComponent;
 
 public class Basket : ViewComponent
 {
-    private readonly IBasketViewModelService _basketService;
+    private readonly IBasketViewModelService _basketViewModelService;
+    private readonly IReadRepository<BasketEntity> _basketRepository;
     private readonly SignInManager<ApplicationUser> _signInManager;
 
-    public Basket(IBasketViewModelService basketService,
+    public Basket(IBasketViewModelService basketViewModelService,
-                    SignInManager<ApplicationUser> signInManager)
+        IReadRepository<BasketEntity> basketRepository,
+        SignInManager<ApplicationUser> signInManager)
     {
-        _basketService = basketService;
+        _basketViewModelService = basketViewModelService;
+        _basketRepository = basketRepository;
         _signInManager = signInManager;
     }
 
@@ -33,18 +39,26 @@ public class Basket : ViewComponent
     {
         if (_signInManager.IsSignedIn(HttpContext.User))
         {
-            return await _basketService.CountTotalBasketItems(User.Identity.Name);
+            var userNameSpec = new BasketWithItemsSpecification(User.Identity.Name);
+            
+            var userBasket = await _basketRepository.GetBySpecAsync(userNameSpec);
+            if (userBasket == null) return 0;
+            return userBasket.TotalItems;
         }
 
         string anonymousId = GetAnnonymousIdFromCookie();
         if (anonymousId == null)
             return 0;
 
-        return await _basketService.CountTotalBasketItems(anonymousId);
+        var anonymousSpec = new BasketWithItemsSpecification(anonymousId);
+        var anonymousBasket = await _basketRepository.GetBySpecAsync(anonymousSpec);
+        if (anonymousBasket == null) return 0;
+        return anonymousBasket.TotalItems;
     }
 
     private string GetAnnonymousIdFromCookie()
     {
+        // TODO: Add a prefix to anonymous cookie values so they cannot collide with user names
         if (Request.Cookies.ContainsKey(Constants.BASKET_COOKIENAME))
         {
             var id = Request.Cookies[Constants.BASKET_COOKIENAME];

src/Web/Services/BasketViewModelService.cs

@@ -14,17 +14,14 @@ public class BasketViewModelService : IBasketViewModelService
 {
     private readonly IRepository<Basket> _basketRepository;
     private readonly IUriComposer _uriComposer;
-    private readonly IBasketQueryService _basketQueryService;
+    private readonly IReadRepository<CatalogItem> _itemRepository;
-    private readonly IRepository<CatalogItem> _itemRepository;
 
     public BasketViewModelService(IRepository<Basket> basketRepository,
-        IRepository<CatalogItem> itemRepository,
+        IReadRepository<CatalogItem> itemRepository,
-        IUriComposer uriComposer,
+        IUriComposer uriComposer)
-        IBasketQueryService basketQueryService)
     {
         _basketRepository = basketRepository;
         _uriComposer = uriComposer;
-        _basketQueryService = basketQueryService;
         _itemRepository = itemRepository;
     }
 
@@ -86,11 +83,4 @@ public class BasketViewModelService : IBasketViewModelService
             Items = await GetBasketItems(basket.Items)
         };
     }
-
-    public async Task<int> CountTotalBasketItems(string username)
-    {
-        var counter = await _basketQueryService.CountTotalBasketItems(username);
-
-        return counter;
-    }
 }

tests/UnitTests/ApplicationCore/Entities/BasketTests/BasketTotalItems.cs

@@ -0,0 +1,35 @@
+using Microsoft.eShopWeb.ApplicationCore.Entities.BasketAggregate;
+using Xunit;
+
+namespace Microsoft.eShopWeb.UnitTests.ApplicationCore.Entities.BasketTests;
+
+public class BasketTotalItems
+{
+    private readonly int _testCatalogItemId = 123;
+    private readonly decimal _testUnitPrice = 1.23m;
+    private readonly int _testQuantity = 2;
+    private readonly string _buyerId = "Test buyerId";
+
+    [Fact]
+    public void ReturnsTotalQuantityWithOneItem()
+    {
+        var basket = new Basket(_buyerId);
+        basket.AddItem(_testCatalogItemId, _testUnitPrice, _testQuantity);
+
+        var result = basket.TotalItems;
+
+        Assert.Equal(_testQuantity, result);
+    }
+
+    [Fact]
+    public void ReturnsTotalQuantityWithMultipleItems()
+    {
+        var basket = new Basket(_buyerId);
+        basket.AddItem(_testCatalogItemId, _testUnitPrice, _testQuantity);
+        basket.AddItem(_testCatalogItemId, _testUnitPrice, _testQuantity*2);
+
+        var result = basket.TotalItems;
+
+        Assert.Equal(_testQuantity*3, result);
+    }
+}