Implemented full dependency chain with auto-wiring. Updated example controller with something more realistic

Author: nref-dan

src/OpenPerpetuum.Api.sln

@@ -9,6 +9,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "OpenPerpetuum.Core.Extensio
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "OpenPerpetuum.Core.DataServices", "OpenPerpetuum.Core.DataServices\OpenPerpetuum.Core.DataServices.csproj", "{E11E68A3-3E71-44DB-8536-21813AA9D1A9}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "OpenPerpetuum.Core.Foundation", "OpenPerpetuum.Core.Foundation\OpenPerpetuum.Core.Foundation.csproj", "{D86CC47A-88C2-49DB-8B36-ED14471D03A2}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -27,6 +29,10 @@ Global
 		{E11E68A3-3E71-44DB-8536-21813AA9D1A9}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{E11E68A3-3E71-44DB-8536-21813AA9D1A9}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{E11E68A3-3E71-44DB-8536-21813AA9D1A9}.Release|Any CPU.Build.0 = Release|Any CPU
+		{D86CC47A-88C2-49DB-8B36-ED14471D03A2}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{D86CC47A-88C2-49DB-8B36-ED14471D03A2}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{D86CC47A-88C2-49DB-8B36-ED14471D03A2}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{D86CC47A-88C2-49DB-8B36-ED14471D03A2}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

src/OpenPerpetuum.Api/Controllers/ApiControllerBase.cs

@@ -0,0 +1,20 @@
+using Microsoft.AspNetCore.Mvc;
+using OpenPerpetuum.Core.Foundation.Processing;
+
+namespace OpenPerpetuum.Api.Controllers
+{
+	public class ApiControllerBase : Controller
+	{
+		private readonly ICoreContext CoreContext;
+
+		protected ICommandProcessor CommandProcessor => CoreContext.CommandProcessor;
+		protected IQueryProcessor QueryProcessor => CoreContext.QueryProcessor;
+		protected IGenericContext GenericContext => CoreContext.GenericContext;
+		protected IIdGeneratorService IdGenerator => CoreContext.IdGenerator;
+
+		public ApiControllerBase(ICoreContext coreContext)
+		{
+			CoreContext = coreContext;
+		}
+	}
+}

src/OpenPerpetuum.Api/Controllers/ValuesController.cs

@@ -1,45 +1,27 @@
-using System;
+using Microsoft.AspNetCore.Mvc;
+using OpenPerpetuum.Core.Foundation.Processing;
 using System.Collections.Generic;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore.Mvc;
 
 namespace OpenPerpetuum.Api.Controllers
 {
-    [Route("api/[controller]")]
+	[Route("api/[controller]")]
     [ApiController]
-    public class ValuesController : ControllerBase
+    public class ValuesController : ApiControllerBase
     {
-        // GET api/values
-        [HttpGet]
-        public ActionResult<IEnumerable<string>> Get()
-        {
-            return new string[] { "value1", "value2" };
-        }
+		public ValuesController(ICoreContext coreContext) : base(coreContext)
+		{ }
 
-        // GET api/values/5
+        // GET api/values
         [HttpGet("{id}")]
-        public ActionResult<string> Get(int id)
+        public ActionResult<IEnumerable<string>> Get(int id)
         {
-            return "value";
-        }
+			if (id < 10)
+				return BadRequest(new { Message = "Use ID 10 - 100 to generate NotFound. USe ID 101+ to return OK" });
 
-        // POST api/values
-        [HttpPost]
-        public void Post([FromBody] string value)
-        {
-        }
+			if (id <= 100)
+				return NotFound();
 
-        // PUT api/values/5
-        [HttpPut("{id}")]
-        public void Put(int id, [FromBody] string value)
-        {
-        }
-
-        // DELETE api/values/5
-        [HttpDelete("{id}")]
-        public void Delete(int id)
-        {
+			return Ok(new string[] { "value1", "value2", GenericContext.CurrentDateTime.ToString("yyyy/MM/dd HH:mm:ss") });
         }
     }
 }

src/OpenPerpetuum.Api/DependencyInstallers/AssemblyLoader.cs

@@ -0,0 +1,25 @@
+using Microsoft.Extensions.DependencyModel;
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+using System.Reflection;
+
+namespace OpenPerpetuum.Api.DependencyInstallers
+{
+	internal sealed class AssemblyLoader
+	{
+		private static readonly Lazy<AssemblyLoader> lazy = new Lazy<AssemblyLoader>(() => new AssemblyLoader());
+		public static AssemblyLoader Instance {  get { return lazy.Value; } }
+
+		private readonly List<Assembly> runtimeAssemblies = new List<Assembly>();
+		private AssemblyLoader()
+		{
+			var platform = Environment.OSVersion.Platform.ToString();
+			runtimeAssemblies = DependencyContext.Default.GetRuntimeAssemblyNames(platform).Where(an => an.Name.StartsWith("OpenPerpetuum")).Select(Assembly.Load).ToList();
+		}
+
+		public ReadOnlyCollection<Assembly> RuntimeAssemblies => runtimeAssemblies.AsReadOnly();
+
+	}
+}

src/OpenPerpetuum.Api/DependencyInstallers/PerpetuumInstaller.cs

@@ -0,0 +1,29 @@
+using OpenPerpetuum.Core.DataServices.Context;
+using OpenPerpetuum.Core.DataServices.CQRS;
+using OpenPerpetuum.Core.DataServices.Database.Interfaces;
+using OpenPerpetuum.Core.Foundation.Processing;
+using SimpleInjector;
+using System.Collections.Generic;
+using System.Reflection;
+
+namespace OpenPerpetuum.Api.DependencyInstallers
+{
+	public static class PerpetuumInstaller
+	{
+		public static void RegisterPerpetuumApiTypes(this Container container)
+		{
+			IEnumerable<Assembly> asm = AssemblyLoader.Instance.RuntimeAssemblies;
+			container.Register(typeof(ICommandHandler<>), asm);
+			// Example of how to add decorators to the handlers via IoC -> container.RegisterDecorator(typeof(ICommandHandler<>), typeof(Extension.DecoratedHandler<>));
+			container.Register(typeof(IQueryHandler<,>), asm);
+
+			// Manually wire the processors. These are being auto-wired to allow for inaccessible class registration
+			container.Register<ICommandProcessor, BasicCommandProcessor>();
+			container.Register<IQueryProcessor, BasicQueryProcessor>();
+			container.Register<IIdGeneratorService, IdGeneratorService>();
+			container.Register<IGenericContext, GenericContext>();
+			container.Register<IDataContext, DataContext>();
+			container.Register<ICoreContext, CoreContext>();
+		}
+	}
+}

src/OpenPerpetuum.Api/OpenPerpetuum.Api.csproj

@@ -26,6 +26,8 @@
   </ItemGroup>
 
   <ItemGroup>
+    <ProjectReference Include="..\OpenPerpetuum.Core.DataServices\OpenPerpetuum.Core.DataServices.csproj" />
+    <ProjectReference Include="..\OpenPerpetuum.Core.Foundation\OpenPerpetuum.Core.Foundation.csproj" />
     <ProjectReference Include="..\OpenPerpetuum.Core\OpenPerpetuum.Core.Extensions\OpenPerpetuum.Core.Extensions.csproj" />
   </ItemGroup>
 

src/OpenPerpetuum.Api/Program.cs

@@ -1,16 +1,9 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore;
+using Microsoft.AspNetCore;
 using Microsoft.AspNetCore.Hosting;
-using Microsoft.Extensions.Configuration;
-using Microsoft.Extensions.Logging;
 
 namespace OpenPerpetuum.Api
 {
-    public class Program
+	public class Program
     {
         public static void Main(string[] args)
         {

src/OpenPerpetuum.Api/Startup.cs

@@ -19,6 +19,7 @@
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.EventLog;
 using Microsoft.Extensions.Options;
+using OpenPerpetuum.Api.DependencyInstallers;
 using OpenPerpetuum.Core.Extensions;
 using SimpleInjector;
 using SimpleInjector.Integration.AspNetCore.Mvc;
@@ -201,10 +202,11 @@ private void InitialiseContainer(IApplicationBuilder app, ILoggerFactory loggerF
             container.RegisterInstance<Func<IViewBufferScope>>(() => app.GetRequestService<IViewBufferScope>());
             container.RegisterInstance(typeof(IServiceProvider), container); // Self registration; basically enables witchcraft...
 
-            // Add Middleware here!
-            // Note that the order in which you enable them in Configure/ConfigureServices is important!
+			// Add Middleware here!
+			// Note that the order in which you enable them in Configure/ConfigureServices is important!
 
-            // Add "Other Stuff" here! (I typically use Dependency Installers rather than list all my deps here)
+			// Add "Other Stuff" here! (I typically use Dependency Installers rather than list all my deps here)
+			container.RegisterPerpetuumApiTypes();
         }
 
         // This should stop the API from returning 302 redirects (attempts to present you a login page) for 401 Unauthorised

src/OpenPerpetuum.Core.DataServices/CQRS/BasicCommandProcessor.cs

@@ -0,0 +1,27 @@
+using OpenPerpetuum.Core.Foundation.Processing;
+using System;
+
+namespace OpenPerpetuum.Core.DataServices.CQRS
+{
+	public class BasicCommandProcessor : ICommandProcessor
+	{
+		private readonly IServiceProvider serviceProvider;
+
+		public BasicCommandProcessor(IServiceProvider serviceProvider)
+		{
+			this.serviceProvider = serviceProvider;
+		}
+		
+		public void Process<TCommand>(TCommand command) where TCommand : ICommand
+		{
+			var handlerType = typeof(ICommandHandler<>).MakeGenericType(typeof(TCommand));
+
+			dynamic handler = serviceProvider.GetService(handlerType);
+
+			if (handler == null)
+				throw new EntryPointNotFoundException($"Unable to find the requested service \"{handlerType.FullName}\"");
+
+			handler.Handle((dynamic)command);
+		}
+	}
+}

src/OpenPerpetuum.Core.DataServices/CQRS/BasicQueryProcessor.cs

@@ -0,0 +1,26 @@
+using OpenPerpetuum.Core.Foundation.Processing;
+using System;
+
+namespace OpenPerpetuum.Core.DataServices.CQRS
+{
+	public class BasicQueryProcessor : IQueryProcessor
+	{
+		private readonly IServiceProvider serviceProvider;
+
+		public BasicQueryProcessor(IServiceProvider serviceProvider)
+		{
+			this.serviceProvider = serviceProvider;
+		}
+
+		public TResult Process<TResult>(IQuery<TResult> query)
+		{
+			var handlerType = typeof(IQueryHandler<,>).MakeGenericType(query.GetType(), typeof(TResult));
+			// I would rather use GetRequiredService but that requires a dependency on the whole MS IoC chain
+			dynamic handler = serviceProvider.GetService(handlerType);
+			if (handler == null)
+				throw new EntryPointNotFoundException($"Unable to find the requested service \"{handlerType.FullName}\"");
+
+			return handler.Handle((dynamic)query);
+		}
+	}
+}