fleshing out backend

Author: Aaronontheweb

src/cqrs/cqrs-sqlserver/CqrsSqlServer.Backend/Actors/GenericChildPerEntityParent.cs

@@ -0,0 +1,43 @@
+// -----------------------------------------------------------------------
+//  <copyright file="GenericChildPerEntityParent.cs" company="Akka.NET Project">
+//      Copyright (C) 2013-2024 .NET Foundation <https://github.com/akkadotnet/akka.net>
+// </copyright>
+// -----------------------------------------------------------------------
+
+using Akka.Actor;
+using Akka.Cluster.Sharding;
+
+namespace CqrsSqlServer.Backend.Actors;
+
+/// <summary>
+/// A generic "child per entity" parent actor.
+/// </summary>
+/// <remarks>
+/// Intended for simplifying unit tests where we don't want to use Akka.Cluster.Sharding.
+/// </remarks>
+public sealed class GenericChildPerEntityParent : ReceiveActor
+{
+    public static Props Props(IMessageExtractor extractor, Func<string, Props> propsFactory)
+    {
+        return Akka.Actor.Props.Create(() => new GenericChildPerEntityParent(extractor, propsFactory));
+    }
+    
+    /*
+     * Re-use Akka.Cluster.Sharding's infrastructure here to keep things simple.
+     */
+    private readonly IMessageExtractor _extractor;
+    private Func<string, Props> _propsFactory;
+
+    public GenericChildPerEntityParent(IMessageExtractor extractor, Func<string, Props> propsFactory)
+    {
+        _extractor = extractor;
+        _propsFactory = propsFactory;
+        
+        ReceiveAny(o =>
+        {
+            var result = _extractor.EntityId(o);
+            if (result is null) return;
+            Context.Child(result).GetOrElse(() => Context.ActorOf(propsFactory(result), result)).Forward(_extractor.EntityMessage(o));
+        });
+    }
+}

src/cqrs/cqrs-sqlserver/CqrsSqlServer.Backend/CqrsSqlServer.Backend.csproj

@@ -8,6 +8,7 @@
     </PropertyGroup>
 
     <ItemGroup>
+        <ProjectReference Include="..\CqrsSqlServer.DataModel\CqrsSqlServer.DataModel.csproj" />
         <ProjectReference Include="..\CqrsSqlServer.Shared\CqrsSqlServer.Shared.csproj"/>
     </ItemGroup>
 

src/cqrs/cqrs-sqlserver/CqrsSqlServer.Backend/Program.cs

@@ -1,3 +1,52 @@
-// See https://aka.ms/new-console-template for more information
+using Akka.Actor;
+using Akka.Hosting;
+using Akka.Persistence.SqlServer.Hosting;
+using CqrsSqlServer.Backend.Actors;
+using CqrsSqlServer.DataModel;
+using CqrsSqlServer.Shared.Serialization;
+using CqrsSqlServer.Shared.Sharding;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
 
-Console.WriteLine("Hello, World!");
+var environment = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT") ?? "Development";
+
+var hostBuilder = new HostBuilder()
+    .ConfigureAppConfiguration((hostContext, configApp) =>
+    {
+        configApp.AddEnvironmentVariables()
+            .AddJsonFile("appsettings.json")
+            .AddJsonFile($"appsettings.{environment}.json");
+    })
+    .ConfigureServices((hostContext, services) =>
+    {
+        var connectionString = hostContext.Configuration.GetConnectionString("AkkaSqlConnection");
+        if (connectionString is null)
+            throw new Exception("AkkaSqlConnection setting is missing");
+
+        services.AddDbContext<CqrsSqlServerContext>(options =>
+        {
+            // disable change tracking for all implementations of this context
+            options.UseQueryTrackingBehavior(QueryTrackingBehavior.NoTracking);
+            options.UseSqlServer(connectionString);
+        });
+
+        services.AddAkka("CqrsProjections", (builder, provider) =>
+        {
+            builder
+                .AddAppSerialization()
+                .WithSqlServerPersistence(connectionString)
+                .WithActors((system, registry, resolver) =>
+                {
+                    var parentActor =
+                        system.ActorOf(
+                            Props.Create(() => new GenericChildPerEntityParent(new ProductMessageRouter(),
+                                ProductTotalsActor.GetProps)), "productTotals");
+                    
+                    registry.Register<ProductTotalsActor>(parentActor);
+                });
+        });
+    });
+
+await hostBuilder.Build().RunAsync();

src/cqrs/cqrs-sqlserver/CqrsSqlServer.Shared/Serialization/SerializationHostingExtensions.cs

@@ -1,15 +1,15 @@
-// using Akka.Hosting;
-//
-// namespace CqrsSqlServer.Shared.Serialization;
-//
-// public static class SerializationHostingExtensions
-// {
-//     /// <summary>
-//     /// Configures the custom serialization for the SqlSharding App.
-//     /// </summary>
-//     public static AkkaConfigurationBuilder AddAppSerialization(this AkkaConfigurationBuilder builder)
-//     {
-//         return builder.WithCustomSerializer("sql-sharding", new[] { typeof(ISqlShardingProtocolMember) },
-//             system => new MessageSerializer(system));
-//     }
-// }
+using Akka.Hosting;
+
+namespace CqrsSqlServer.Shared.Serialization;
+
+public static class SerializationHostingExtensions
+{
+    /// <summary>
+    /// Configures the custom serialization for the SqlSharding App.
+    /// </summary>
+    public static AkkaConfigurationBuilder AddAppSerialization(this AkkaConfigurationBuilder builder)
+    {
+        return builder.WithCustomSerializer("sql-sharding", new[] { typeof(ISqlShardingProtocolMember) },
+            system => new MessageSerializer(system));
+    }
+}