Create basic CustomWebApplicationFactory.

tests/CleanArchitecture.Tests/CleanArchitecture.Tests.csproj

@@ -28,6 +28,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="2.1.0" />
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="2.1.0" />
     <PackageReference Include="Microsoft.AspNetCore.TestHost" Version="2.1.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.7.2" />
     <PackageReference Include="Moq" Version="4.8.2" />

tests/CleanArchitecture.Tests/Integration/Web/CustomWebApplicationFactory.cs

+using CleanArchitecture.Infrastructure.Data;
+using CleanArchitecture.Web;
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.Mvc.Testing;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
+using System;
+
+namespace CleanArchitecture.Tests.Integration.Web
+{
+    public class CustomWebApplicationFactory<TStartup> : WebApplicationFactory<Startup>
+    {
+        protected override void ConfigureWebHost(IWebHostBuilder builder)
+        {
+            builder.ConfigureServices(services =>
+            {
+                // Create a new service provider.
+                var serviceProvider = new ServiceCollection()
+                    .AddEntityFrameworkInMemoryDatabase()
+                    .BuildServiceProvider();
+
+                // Add a database context (ApplicationDbContext) using an in-memory
+                // database for testing.
+                services.AddDbContext<AppDbContext>(options =>
+                {
+                    options.UseInMemoryDatabase("InMemoryDbForTesting");
+                    options.UseInternalServiceProvider(serviceProvider);
+                });
+
+                // Build the service provider.
+                var sp = services.BuildServiceProvider();
+
+                // Create a scope to obtain a reference to the database
+                // context (ApplicationDbContext).
+                using (var scope = sp.CreateScope())
+                {
+                    var scopedServices = scope.ServiceProvider;
+                    var db = scopedServices.GetRequiredService<AppDbContext>();
+
+                    var logger = scopedServices
+                        .GetRequiredService<ILogger<CustomWebApplicationFactory<TStartup>>>();
+
+                    // Ensure the database is created.
+                    db.Database.EnsureCreated();
+
+                    try
+                    {
+                        // Seed the database with test data.
+                        SeedData.PopulateTestData(db);
+                    }
+                    catch (Exception ex)
+                    {
+                        logger.LogError(ex, $"An error occurred seeding the " +
+                            "database with test messages. Error: {ex.Message}");
+                    }
+                }
+            });
+        }
+    }
+}