Allow user to delete a product (#5)

src/Admin/NCafe.Admin.Api/Program.cs

@@ -59,6 +59,12 @@
 })
 .WithName("CreateProduct");
 
+app.MapDelete("/products/{id}", async (IMediator mediator, Guid id) =>
+{
+    await mediator.Send(new DeleteProduct(id));
+    return Results.NoContent();
+}).WithName("DeleteProduct");
+
 app.MapGet("/healthz", () => "OK");
 
 app.Run();

src/Admin/NCafe.Admin.Api/Projections/ProductProjectionService.cs

@@ -18,6 +18,12 @@ public ProductProjectionService(IProjectionService<Product> projectionService)
             Name = @event.Name,
             Price = @event.Price
         });
+
+        projectionService.OnUpdate<ProductDeleted>(
+            product => product.Id,
+            (@event, product) => product.IsDeleted = true);
+
+
     }
 
     protected async override Task ExecuteAsync(CancellationToken stoppingToken)

src/Admin/NCafe.Admin.Domain.Tests/Commands/DeleteProductTests.cs

@@ -0,0 +1,49 @@
+using NCafe.Admin.Domain.Commands;
+using NCafe.Admin.Domain.Entities;
+using NCafe.Admin.Domain.Exceptions;
+using NCafe.Core.Repositories;
+using System.Threading;
+
+namespace NCafe.Admin.Domain.Tests.Commands;
+
+public class DeleteProductTests
+{
+    private readonly DeleteProductHandler _sut;
+    private readonly IRepository _repository;
+
+    public DeleteProductTests()
+    {
+        _repository = A.Fake<IRepository>();
+        _sut = new DeleteProductHandler(_repository);
+    }
+
+    [Fact]
+    public async Task GivenNonExistingProduct_ShouldThrowException()
+    {
+        // Arrange
+        var id = Guid.NewGuid();
+        A.CallTo(() => _repository.GetById<Product>(id)).Returns((Product)null);
+
+        // Act
+        var exception = await Record.ExceptionAsync(() => _sut.Handle(new DeleteProduct(id), CancellationToken.None));
+
+        // Assert
+        exception.ShouldBeOfType<ProductNotFound>();
+    }
+
+    [Fact]
+    public async Task GivenExistingProduct_ShouldDeleteProduct()
+    {
+        // Arrange
+        var id = Guid.NewGuid();
+        var product = new Product(id, "Latte", 3);
+        A.CallTo(() => _repository.GetById<Product>(id)).Returns(product);
+
+        // Act
+        await _sut.Handle(new DeleteProduct(id), CancellationToken.None);
+
+        // Assert
+        A.CallTo(() => _repository.Save(A<Product>.That.Matches(p => p.Id == id && p.IsDeleted == true)))
+            .MustHaveHappenedOnceExactly();
+    }
+}

src/Admin/NCafe.Admin.Domain/Commands/DeleteProduct.cs

@@ -0,0 +1,25 @@
+using MediatR;
+using NCafe.Admin.Domain.Entities;
+using NCafe.Admin.Domain.Exceptions;
+using NCafe.Core.Repositories;
+
+namespace NCafe.Admin.Domain.Commands;
+
+public record DeleteProduct(Guid Id) : IRequest;
+
+internal sealed class DeleteProductHandler(IRepository repository) : IRequestHandler<DeleteProduct>
+{
+    private readonly IRepository _repository = repository;
+
+    public async Task Handle(DeleteProduct command, CancellationToken cancellationToken)
+    {
+        var product = await _repository.GetById<Product>(command.Id);
+        if (product is null || product.IsDeleted)
+        {
+            throw new ProductNotFound(command.Id);
+        }
+
+        product.Delete();
+        await _repository.Save(product);
+    }
+}

src/Admin/NCafe.Admin.Domain/Entities/Product.cs

@@ -32,11 +32,22 @@ public Product(Guid id, string name, decimal price)
 
     public string Name { get; private set; }
     public decimal Price { get; private set; }
+    public bool IsDeleted { get; private set; }
 
     private void Apply(ProductCreated @event)
     {
         Id = @event.Id;
         Name = @event.Name;
         Price = @event.Price;
     }
+
+    public void Delete()
+    {
+        RaiseEvent(new ProductDeleted(Id));
+    }
+
+    private void Apply(ProductDeleted _)
+    {
+        IsDeleted = true;
+    }
 }

src/Admin/NCafe.Admin.Domain/Events/ProductDeleted.cs

@@ -0,0 +1,11 @@
+using NCafe.Core.Domain;
+
+namespace NCafe.Admin.Domain.Events;
+
+public sealed record ProductDeleted : Event
+{
+    public ProductDeleted(Guid id)
+    {
+        Id = id;
+    }
+}

src/Admin/NCafe.Admin.Domain/Exceptions/ProductNotFound.cs

@@ -0,0 +1,5 @@
+using NCafe.Core.Exceptions;
+
+namespace NCafe.Admin.Domain.Exceptions;
+
+public class ProductNotFound(Guid id) : DomainException($"Product with id '{id}' was not found.");

src/Admin/NCafe.Admin.Domain/Queries/GetProducts.cs

@@ -13,6 +13,7 @@ internal sealed class GetProductsHandler(IReadModelRepository<Product> productRe
     public Task<Product[]> Handle(GetProducts query, CancellationToken cancellation)
     {
         var products = _productRepository.GetAll()
+            .Where(p => !p.IsDeleted)
             .ToArray();
         return Task.FromResult(products);
     }

src/Admin/NCafe.Admin.Domain/ReadModels/Product.cs

@@ -6,4 +6,5 @@ public sealed class Product : ReadModel
 {
     public string Name { get; set; }
     public decimal Price { get; set; }
+    public bool IsDeleted { get; set; }
 }

src/Cashier/NCafe.Cashier.Api/Program.cs

@@ -88,4 +88,4 @@
 
 app.Run();
 
-public partial class Program { }
+public partial class Program;

src/Cashier/NCafe.Cashier.Api/Projections/ProductDeleted.cs

@@ -0,0 +1,11 @@
+using NCafe.Core.Domain;
+
+namespace NCafe.Cashier.Api.Projections;
+
+public sealed record ProductDeleted : Event
+{
+    public ProductDeleted(Guid id)
+    {
+        Id = id;
+    }
+}

src/Cashier/NCafe.Cashier.Api/Projections/ProductProjectionService.cs

@@ -15,8 +15,12 @@ public ProductProjectionService(IProjectionService<Product> projectionService)
         {
             Id = @event.Id,
             Name = @event.Name,
-            Price = @event.Price
+            Price = @event.Price,
         });
+
+        projectionService.OnUpdate<ProductDeleted>(
+            product => product.Id,
+            (@event, product) => product.IsDeleted = true);
     }
 
     protected async override Task ExecuteAsync(CancellationToken stoppingToken)

src/Cashier/NCafe.Cashier.Domain/Queries/GetProducts.cs

@@ -14,6 +14,7 @@ internal sealed class GetProductsHandler(IReadModelRepository<Product> productRe
     public Task<Product[]> Handle(GetProducts request, CancellationToken cancellationToken)
     {
         var products = _productRepository.GetAll()
+            .Where(p => !p.IsDeleted)
             .ToArray();
         return Task.FromResult(products);
     }

src/Cashier/NCafe.Cashier.Domain/ReadModels/Product.cs

@@ -6,4 +6,5 @@ public sealed class Product : ReadModel
 {
     public string Name { get; set; }
     public decimal Price { get; set; }
+    public bool IsDeleted { get; set; }
 }

src/Common/NCafe.Infrastructure/EventStore/EventStoreProjectionService.cs

@@ -1,4 +1,4 @@
-using EventStore.Client;
+using EventStore.Client;
 using Microsoft.Extensions.Logging;
 using NCafe.Core.Domain;
 using NCafe.Core.Projections;
@@ -51,7 +51,8 @@ private Task EventAppeared(StreamSubscription subscription, ResolvedEvent @event
 
     private void SubscriptionDropped(StreamSubscription subscription, SubscriptionDroppedReason reason, Exception exception)
     {
-        _logger.LogError("Subscription Dropped.");
+        _logger.LogError("Subscription Dropped for '{EventStoreStream}' with reason '{SubscriptionDroppedReason}'", subscription.SubscriptionId, reason);
+        _logger.LogError(exception, "{Exception}", exception.Message);
     }
 
     public void OnCreate<TEvent>(Func<TEvent, T> handler) where TEvent : Event

src/UI/NCafe.Web/Pages/Admin/Index.razor

@@ -1,8 +1,10 @@
-@page "/admin"
+@page "/admin"
 @using NCafe.Web.Models
 @inject HttpClient Http
 @inject IConfiguration Configuration
 @inject NavigationManager NavigationManager
+@inject ModalService _modalService
+@inject IMessageService _message
 
 <PageTitle>Admin - NCafe</PageTitle>
 
@@ -22,37 +24,73 @@
     to help mitigate this in a later moment.
 </p>
 
-@if (products == null)
+@if (_products == null)
 {
     <Spin />
+    return;
 }
-else if (!products.Any())
+
+@if (!_products.Any())
 {
     <Result Title="No products to show." />
+    return;
 }
-else
-{
+
+
     <Table TItem="Product"
-           DataSource="@products"
-           Total="@(products.Length)"
+           DataSource="@_products"
+           Total="@(_products.Length)"
            HidePagination="true">
-        <Column @bind-Field="@context.Id" />
         <Column @bind-Field="@context.Name" Sortable />
         <Column @bind-Field="@context.Price" Format="C2" Sortable />
+        <ActionColumn Title="Action">
+            <Space>
+              <SpaceItem><Button Danger OnClick="@(() => ShowDeleteConfirm(context.Id))">Delete</Button></SpaceItem>
+            </Space>
+          </ActionColumn>
     </Table>
-}
+
 
 @code {
-    private Product[] products;
+    private Product[] _products;
 
     protected override async Task OnInitializedAsync()
     {
         var url = $"{Configuration["AdminBaseAddress"]}/products";
-        products = await Http.GetFromJsonAsync<Product[]>(url);
+        _products = await Http.GetFromJsonAsync<Product[]>(url);
     }
 
     void CreateProduct()
     {
         NavigationManager.NavigateTo("admin/create-product");
     }
+
+
+    private async Task ShowDeleteConfirm(Guid id)
+    {
+        var productName = _products.Single(p => p.Id == id).Name;
+        var confirmed = await _modalService.ConfirmAsync(new ConfirmOptions
+        {
+            Title = "Delete item",
+            Content = $"Are you sure you want to delete {productName}?",
+            OkType = "danger",
+            Icon = @<Icon Type="exclamation-circle" Theme="outline"></Icon>
+        });
+
+        if (confirmed)
+        {
+            await DeleteItem(id);
+        }
+    }
+
+    private async Task DeleteItem(Guid id)
+    {
+        var url = $"{Configuration["AdminBaseAddress"]}/products/{id}";
+        var response = await Http.DeleteAsync(url);
+        response.EnsureSuccessStatusCode();
+
+        var product = _products.Single(p => p.Id == id);
+        await _message.Info($"{product.Name} has been deleted.");
+        _products = _products.Where(p => p.Id != id).ToArray();
+    }
 }