Added design time DbContext factory.

Added support appsettings.Local.json (settings specific to an individuals development environment).
Changed default database to LocalDb.

.gitignore

@@ -6,6 +6,7 @@
 *.user
 *.userosscache
 *.sln.docstates
+appsettings.Local.json
 
 # User-specific files (MonoDevelop/Xamarin Studio)
 *.userprefs

Northwind.Persistence/Infrastructure/DesignTimeDbContextFactoryBase.cs

@@ -0,0 +1,53 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Design;
+using Microsoft.Extensions.Configuration;
+using System;
+using System.IO;
+
+namespace Northwind.Persistence.Infrastructure
+{
+    public abstract class DesignTimeDbContextFactoryBase<TContext> :
+        IDesignTimeDbContextFactory<TContext> where TContext : DbContext
+    {
+        private const string ConnectionStringName = "NorthwindDatabase";
+        private const string AspNetCoreEnvironment = "ASPNETCORE_ENVIRONMENT";
+
+        public TContext CreateDbContext(string[] args)
+        {
+            return Create(Directory.GetCurrentDirectory(), Environment.GetEnvironmentVariable(AspNetCoreEnvironment));
+        }
+
+        protected abstract TContext CreateNewInstance(DbContextOptions<TContext> options);
+
+        private TContext Create(string basePath, string environmentName)
+        {
+            var configuration = new ConfigurationBuilder()
+                .SetBasePath(basePath + "\\..\\Northwind..WebUI")
+                .AddJsonFile("appsettings.json")
+                .AddJsonFile($"appsettings.Local.json", optional: true)
+                .AddJsonFile($"appsettings.{environmentName}.json", optional: true)
+                .AddEnvironmentVariables()
+                .Build();
+
+            var connectionString = configuration.GetConnectionString(ConnectionStringName);
+
+            return Create(connectionString);
+        }
+
+        private TContext Create(string connectionString)
+        {
+            if (string.IsNullOrEmpty(connectionString))
+            {
+                throw new ArgumentException($"Connection string '{ConnectionStringName}' is null or empty.", nameof(connectionString));
+            }
+
+            Console.WriteLine($"DesignTimeDbContextFactoryBase.Create(string): Connection string: '{connectionString}'.");
+
+            var optionsBuilder = new DbContextOptionsBuilder<TContext>();
+
+            optionsBuilder.UseSqlServer(connectionString);
+
+            return CreateNewInstance(optionsBuilder.Options);
+        }
+    }
+}

Northwind.Persistence/Northwind.Persistence.csproj

@@ -12,6 +12,9 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="2.1.0" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="2.1.0" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="2.1.0" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" Version="2.1.0" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="2.1.0" />
   </ItemGroup>
 
   <ItemGroup>

Northwind.Persistence/NorthwindDbContextFactory.cs

@@ -0,0 +1,13 @@
+using Microsoft.EntityFrameworkCore;
+using Northwind.Persistence.Infrastructure;
+
+namespace Northwind.Persistence
+{
+    public class NorthwindDbContextFactory : DesignTimeDbContextFactoryBase<NorthwindDbContext>
+    {
+        protected override NorthwindDbContext CreateNewInstance(DbContextOptions<NorthwindDbContext> options)
+        {
+            return new NorthwindDbContext(options);
+        }
+    }
+}

Northwind.WebUI/Program.cs

@@ -1,10 +1,11 @@
-using Microsoft.AspNetCore;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using Northwind.Persistence;
 using Microsoft.EntityFrameworkCore;
 using System;
+using System.IO;
+using Microsoft.Extensions.Configuration;
 
 namespace Northwind.WebUI
 {
@@ -26,14 +27,31 @@ public static void Main(string[] args)
                 catch (Exception ex)
                 {
                     var logger = scope.ServiceProvider.GetRequiredService<ILogger<Program>>();
-                    logger.LogError(ex, "An error occurred while migrating the database.");
+                    logger.LogError(ex, "An error occurred while migrating or initializing the database.");
                 }
             }
 
             host.Run();
         }
+
         public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
-            WebHost.CreateDefaultBuilder(args)
+            new WebHostBuilder()
+                .UseKestrel()
+                .UseContentRoot(Directory.GetCurrentDirectory())
+                .ConfigureAppConfiguration((hostingContext, config) =>
+                {
+                    var env = hostingContext.HostingEnvironment;
+                    config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
+                          .AddJsonFile($"appsettings.Local.json", optional: true, reloadOnChange: true)
+                          .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true, reloadOnChange: true);
+                    config.AddEnvironmentVariables();
+                })
+                .ConfigureLogging((hostingContext, logging) =>
+                {
+                    logging.AddConfiguration(hostingContext.Configuration.GetSection("Logging"));
+                    logging.AddConsole();
+                    logging.AddDebug();
+                })
                 .UseStartup<Startup>();
     }
 }

Northwind.WebUI/Properties/launchSettings.json

@@ -0,0 +1,27 @@
+{
+  "iisSettings": {
+    "windowsAuthentication": false,
+    "anonymousAuthentication": true,
+    "iisExpress": {
+      "applicationUrl": "http://localhost:52467/",
+      "sslPort": 0
+    }
+  },
+  "profiles": {
+    "IIS Express": {
+      "commandName": "IISExpress",
+      "launchBrowser": true,
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "Northwind.WebUI": {
+      "commandName": "Project",
+      "launchBrowser": true,
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      },
+      "applicationUrl": "http://localhost:52468/"
+    }
+  }
+}