Add support for dependency injection

GenHTTP.slnx

@@ -1,19 +1,15 @@
 <Solution>
-
   <Folder Name="/Adapters/">
     <Project Path="Adapters\AspNetCore\GenHTTP.Adapters.AspNetCore.csproj" />
   </Folder>
-
   <Folder Name="/API/">
     <Project Path="API\GenHTTP.Api.csproj" />
   </Folder>
-
   <Folder Name="/Engine/">
     <Project Path="Engine\Internal\GenHTTP.Engine.Internal.csproj" />
     <Project Path="Engine\Kestrel\GenHTTP.Engine.Kestrel.csproj" />
     <Project Path="Engine\Shared\GenHTTP.Engine.Shared.csproj" />
   </Folder>
-
   <Folder Name="/Modules/">
     <Project Path="Modules\ApiBrowsing\GenHTTP.Modules.ApiBrowsing.csproj" />
     <Project Path="Modules\Authentication\GenHTTP.Modules.Authentication.csproj" />
@@ -23,6 +19,7 @@
     <Project Path="Modules\Compression\GenHTTP.Modules.Compression.csproj" />
     <Project Path="Modules\Controllers\GenHTTP.Modules.Controllers.csproj" />
     <Project Path="Modules\Conversion\GenHTTP.Modules.Conversion.csproj" />
+    <Project Path="Modules\DependencyInjection\GenHTTP.Modules.DependencyInjection.csproj" />
     <Project Path="Modules\DirectoryBrowsing\GenHTTP.Modules.DirectoryBrowsing.csproj" />
     <Project Path="Modules\ErrorHandling\GenHTTP.Modules.ErrorHandling.csproj" />
     <Project Path="Modules\Functional\GenHTTP.Modules.Functional.csproj" />
@@ -46,29 +43,23 @@
     <Project Path="Modules\Webservices\GenHTTP.Modules.Webservices.csproj" />
     <Project Path="Modules\Websockets\GenHTTP.Modules.Websockets.csproj" />
   </Folder>
-
   <Folder Name="/Playground/">
     <Project Path="Playground\GenHTTP.Playground.csproj" />
   </Folder>
-
-  <Folder Name="/Testing/">
-    <Project Path="Testing\Acceptance\GenHTTP.Testing.Acceptance.csproj" />
-    <Project Path="Testing\Testing\GenHTTP.Testing.csproj" />
-  </Folder>
-
   <Folder Name="/Solution Items/">
     <File Path="CONTRIBUTING.md" />
     <File Path="LICENSE" />
     <File Path="README.md" />
   </Folder>
-
   <Folder Name="/Solution Items/Packages/">
     <File Path="Packages\GenHTTP.Core.Kestrel.nuspec" />
     <File Path="Packages\GenHTTP.Core.nuspec" />
   </Folder>
-
   <Folder Name="/Solution Items/Resources/">
     <File Path="Resources\icon.png" />
   </Folder>
-
+  <Folder Name="/Testing/">
+    <Project Path="Testing\Acceptance\GenHTTP.Testing.Acceptance.csproj" />
+    <Project Path="Testing\Testing\GenHTTP.Testing.csproj" />
+  </Folder>
 </Solution>

Modules/Controllers/Provider/ControllerBuilder.cs

@@ -1,6 +1,9 @@
 using System.Diagnostics.CodeAnalysis;
+
 using GenHTTP.Api.Content;
 using GenHTTP.Api.Infrastructure;
+using GenHTTP.Api.Protocol;
+
 using GenHTTP.Modules.Conversion;
 using GenHTTP.Modules.Conversion.Formatters;
 using GenHTTP.Modules.Conversion.Serializers;
@@ -9,16 +12,18 @@
 
 namespace GenHTTP.Modules.Controllers.Provider;
 
-public sealed class ControllerBuilder : IHandlerBuilder<ControllerBuilder>
+public sealed class ControllerBuilder : IHandlerBuilder<ControllerBuilder>, IRegistryBuilder<ControllerBuilder>
 {
     private readonly List<IConcernBuilder> _Concerns = [];
 
+    private Type? _Type;
+
+    private Func<IRequest, ValueTask<object>>? _InstanceProvider;
+
     private IBuilder<FormatterRegistry>? _Formatters;
 
     private IBuilder<InjectionRegistry>? _Injection;
 
-    private object? _Instance;
-
     private IBuilder<SerializationRegistry>? _Serializers;
 
     #region Functionality
@@ -42,14 +47,25 @@ public ControllerBuilder Formatters(IBuilder<FormatterRegistry> registry)
     }
 
     public ControllerBuilder Type<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] T>() where T : new()
+        => Instance(new T());
+
+    public ControllerBuilder Type([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] Type type)
     {
-        _Instance = new T();
+        _Type = type;
         return this;
     }
 
     public ControllerBuilder Instance(object instance)
     {
-        _Instance = instance;
+        _Type = instance.GetType();
+        _InstanceProvider = (_) => ValueTask.FromResult(instance);
+
+        return this;
+    }
+
+    public ControllerBuilder InstanceProvider(Func<IRequest, ValueTask<object>> provider)
+    {
+        _InstanceProvider = provider;
         return this;
     }
 
@@ -67,11 +83,13 @@ public IHandler Build()
 
         var formatters = (_Formatters ?? Formatting.Default()).Build();
 
-        var instance = _Instance ?? throw new BuilderMissingPropertyException("Instance or Type");
+        var instanceProvider = _InstanceProvider ?? throw new BuilderMissingPropertyException("Instance provider has not been set");
+
+        var type = _Type ?? throw new BuilderMissingPropertyException("Type has not been set");
 
         var extensions = new MethodRegistry(serializers, injectors, formatters);
 
-        return Concerns.Chain(_Concerns, new ControllerHandler(instance, extensions));
+        return Concerns.Chain(_Concerns, new ControllerHandler(type, instanceProvider, extensions));
     }
 
     #endregion

Modules/Controllers/Provider/ControllerHandler.cs

@@ -13,59 +13,74 @@ public sealed partial class ControllerHandler : IHandler, IServiceMethodProvider
 {
     private static readonly Regex HyphenMatcher = CreateHyphenMatcher();
 
+    private MethodCollection? _Methods;
+
     #region Get-/Setters
 
-    public MethodCollection Methods { get; }
+    private Type Type { get; }
 
-    private ResponseProvider ResponseProvider { get; }
+    private Func<IRequest, ValueTask<object>> InstanceProvider { get; }
 
     private MethodRegistry Registry { get; }
 
-    private object Instance { get; }
-
     #endregion
 
     #region Initialization
 
-    public ControllerHandler(object instance, MethodRegistry registry)
+    public ControllerHandler(Type type, Func<IRequest, ValueTask<object>> instanceProvider, MethodRegistry registry)
     {
+        Type = type;
+        InstanceProvider = instanceProvider;
         Registry = registry;
+    }
+
+    #endregion
 
-        Instance = instance;
+    #region Functionality
 
-        ResponseProvider = new ResponseProvider(registry);
+    public ValueTask PrepareAsync() => ValueTask.CompletedTask;
 
-        Methods = new MethodCollection(AnalyzeMethods(instance.GetType(), registry));
-    }
+    public async ValueTask<IResponse?> HandleAsync(IRequest request) => await (await GetMethodsAsync(request)).HandleAsync(request);
 
-    private IEnumerable<MethodHandler> AnalyzeMethods(Type type, MethodRegistry registry)
+    public async ValueTask<MethodCollection> GetMethodsAsync(IRequest request)
     {
-        foreach (var method in type.GetMethods(BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly))
+        if (_Methods != null) return _Methods;
+
+        var found = new List<MethodHandler>();
+
+
+        foreach (var method in Type.GetMethods(BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly))
         {
             var annotation = method.GetCustomAttribute<ControllerActionAttribute>(true) ?? new MethodAttribute();
 
             var arguments = FindPathArguments(method);
 
-            var operation = CreateOperation(method, arguments);
+            var operation = CreateOperation(request, method, arguments, Registry);
 
-            yield return new MethodHandler(operation, Instance, annotation, registry);
+            found.Add(new MethodHandler(operation, InstanceProvider, annotation, Registry));
         }
+
+        var result = new MethodCollection(found);
+
+        await result.PrepareAsync();
+
+        return _Methods = result;
     }
 
-    private Operation CreateOperation(MethodInfo method, List<string> arguments)
+    private static Operation CreateOperation(IRequest request, MethodInfo method, List<string> arguments, MethodRegistry registry)
     {
         var pathArguments = string.Join('/', arguments.Select(a => $":{a}"));
 
         if (method.Name == "Index")
         {
-            return OperationBuilder.Create(pathArguments.Length > 0 ? $"/{pathArguments}/" : null, method, Registry, true);
+            return OperationBuilder.Create(request, pathArguments.Length > 0 ? $"/{pathArguments}/" : null, method, registry, true);
         }
 
         var name = HypenCase(method.Name);
 
         var path = $"/{name}";
 
-        return OperationBuilder.Create(pathArguments.Length > 0 ? $"{path}/{pathArguments}/" : $"{path}/", method, Registry, true);
+        return OperationBuilder.Create(request, pathArguments.Length > 0 ? $"{path}/{pathArguments}/" : $"{path}/", method, registry, true);
     }
 
     private static List<string> FindPathArguments(MethodInfo method)
@@ -93,12 +108,4 @@ private static List<string> FindPathArguments(MethodInfo method)
 
     #endregion
 
-    #region Functionality
-
-    public ValueTask PrepareAsync() => Methods.PrepareAsync();
-
-    public ValueTask<IResponse?> HandleAsync(IRequest request) => Methods.HandleAsync(request);
-
-    #endregion
-
 }

Modules/DependencyInjection/Basics/ConcernIntegration.cs

@@ -0,0 +1,38 @@
+using GenHTTP.Api.Content;
+using GenHTTP.Api.Protocol;
+using GenHTTP.Modules.DependencyInjection.Infrastructure;
+
+namespace GenHTTP.Modules.DependencyInjection.Basics;
+
+internal class ConcernIntegration<T> : IConcern where T : class, IDependentConcern
+{
+
+    #region Getters/Setters
+
+    public IHandler Content { get; }
+
+    #endregion
+
+    #region Initialization
+
+    internal ConcernIntegration(IHandler content)
+    {
+        Content = content;
+    }
+
+    #endregion
+
+    #region Functionality
+
+    public ValueTask PrepareAsync() => Content.PrepareAsync();
+
+    public async ValueTask<IResponse?> HandleAsync(IRequest request)
+    {
+        var instance = await InstanceProvider.ProvideAsync<T>(request);
+
+        return await instance.HandleAsync(Content, request);
+    }
+
+    #endregion
+
+}

Modules/DependencyInjection/Basics/ConcernIntegrationBuilder.cs

@@ -0,0 +1,10 @@
+using GenHTTP.Api.Content;
+
+namespace GenHTTP.Modules.DependencyInjection.Basics;
+
+internal class ConcernIntegrationBuilder<T> : IConcernBuilder where T : class, IDependentConcern
+{
+
+    public IConcern Build(IHandler content) => new ConcernIntegration<T>(content);
+
+}

Modules/DependencyInjection/Basics/HandlerIntegration.cs

@@ -0,0 +1,20 @@
+using GenHTTP.Api.Content;
+using GenHTTP.Api.Protocol;
+
+using GenHTTP.Modules.DependencyInjection.Infrastructure;
+
+namespace GenHTTP.Modules.DependencyInjection.Basics;
+
+internal class HandlerIntegration<T> : IHandler where T: class, IDependentHandler
+{
+
+    public ValueTask PrepareAsync() => ValueTask.CompletedTask;
+
+    public async ValueTask<IResponse?> HandleAsync(IRequest request)
+    {
+        var instance = await InstanceProvider.ProvideAsync<T>(request);
+
+        return await instance.HandleAsync(request);
+    }
+
+}

Modules/DependencyInjection/Basics/HandlerIntegrationBuilder.cs

@@ -0,0 +1,10 @@
+using GenHTTP.Api.Content;
+
+namespace GenHTTP.Modules.DependencyInjection.Basics;
+
+internal class HandlerIntegrationBuilder<T> : IHandlerBuilder where T : class, IDependentHandler
+{
+
+    public IHandler Build() => new HandlerIntegration<T>();
+
+}

Modules/DependencyInjection/Dependent.cs

@@ -0,0 +1,25 @@
+using GenHTTP.Api.Content;
+
+using GenHTTP.Modules.DependencyInjection.Basics;
+
+namespace GenHTTP.Modules.DependencyInjection;
+
+/// <summary>
+/// Allows to enable dependency injection for concerns and handlers.
+/// </summary>
+public static class Dependent
+{
+
+    /// <summary>
+    /// Allows the given class to be used as a regular concern with dependency injection enabled.
+    /// </summary>
+    /// <typeparam name="T">The class implementing the concern</typeparam>
+    public static IConcernBuilder Concern<T>() where T : class, IDependentConcern => new ConcernIntegrationBuilder<T>();
+
+    /// <summary>
+    /// Allows the given class to be used as a regular handler with dependency injection enabled.
+    /// </summary>
+    /// <typeparam name="T">The class implementing the handler</typeparam>
+    public static IHandlerBuilder Handler<T>() where T : class, IDependentHandler => new HandlerIntegrationBuilder<T>();
+
+}

Modules/DependencyInjection/DependentController.cs

@@ -0,0 +1,39 @@
+using System.Diagnostics.CodeAnalysis;
+
+using GenHTTP.Api.Infrastructure;
+
+using GenHTTP.Modules.Controllers.Provider;
+using GenHTTP.Modules.Conversion.Formatters;
+using GenHTTP.Modules.Conversion.Serializers;
+using GenHTTP.Modules.DependencyInjection.Infrastructure;
+using GenHTTP.Modules.Layouting.Provider;
+using GenHTTP.Modules.Reflection.Injectors;
+
+namespace GenHTTP.Modules.DependencyInjection;
+
+public static class DependentController
+{
+
+    /// <summary>
+    /// Adds the given controller to the layout with dependency injection enabled.
+    /// </summary>
+    /// <param name="layout">The layout to add the controller to</param>
+    /// <param name="path">The path to register the controller at</param>
+    /// <param name="injectors">Additional parameter injections to be used by the controller</param>
+    /// <param name="serializers">Additional serializers to be used by the controller</param>
+    /// <param name="formatters">Additional formatters to be used by the controller</param>
+    /// <typeparam name="T">The class implementing the controller</typeparam>
+    /// <returns>The given layout with the specified controller attached</returns>
+    public static LayoutBuilder AddDependentController<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] T>(this LayoutBuilder layout, string path, InjectionRegistryBuilder? injectors = null, IBuilder<SerializationRegistry>? serializers = null, IBuilder<FormatterRegistry>? formatters = null) where T : class
+    {
+        var builder = new ControllerBuilder();
+
+        builder.Type(typeof(T));
+        builder.InstanceProvider(async (r) => await InstanceProvider.ProvideAsync<T>(r));
+
+        builder.Configure(injectors, serializers, formatters);
+
+        return layout.Add(path, builder);
+    }
+
+}