Design extensibility for executors

We have all of these executors but they aren't really
documented/supported for extensibility today. This change introduces a
pattern for action result executors so we can make them extensible.

Author: rynowak

src/Microsoft.AspNetCore.Mvc.Core/ContentResult.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc.Infrastructure;
 using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.Extensions.DependencyInjection;
 
@@ -32,7 +33,7 @@ public override Task ExecuteResultAsync(ActionContext context)
                 throw new ArgumentNullException(nameof(context));
             }
 
-            var executor = context.HttpContext.RequestServices.GetRequiredService<ContentResultExecutor>();
+            var executor = context.HttpContext.RequestServices.GetRequiredService<IActionResultExecutor<ContentResult>>();
             return executor.ExecuteAsync(context, this);
         }
     }

src/Microsoft.AspNetCore.Mvc.Core/DependencyInjection/MvcCoreServiceCollectionExtensions.cs

@@ -243,17 +243,17 @@ internal static void AddMvcCoreServices(IServiceCollection services)
             services.TryAddSingleton<IHttpResponseStreamWriterFactory, MemoryPoolHttpResponseStreamWriterFactory>();
             services.TryAddSingleton(ArrayPool<byte>.Shared);
             services.TryAddSingleton(ArrayPool<char>.Shared);
-            services.TryAddSingleton<ObjectResultExecutor>();
-            services.TryAddSingleton<PhysicalFileResultExecutor>();
-            services.TryAddSingleton<VirtualFileResultExecutor>();
-            services.TryAddSingleton<FileStreamResultExecutor>();
-            services.TryAddSingleton<FileContentResultExecutor>();
-            services.TryAddSingleton<RedirectResultExecutor>();
-            services.TryAddSingleton<LocalRedirectResultExecutor>();
-            services.TryAddSingleton<RedirectToActionResultExecutor>();
-            services.TryAddSingleton<RedirectToRouteResultExecutor>();
-            services.TryAddSingleton<RedirectToPageResultExecutor>();
-            services.TryAddSingleton<ContentResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<ObjectResult>, ObjectResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<PhysicalFileResult>, PhysicalFileResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<VirtualFileResult>, VirtualFileResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<FileStreamResult>, FileStreamResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<FileContentResult>, FileContentResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<RedirectResult>, RedirectResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<LocalRedirectResult>, LocalRedirectResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<RedirectToActionResult>, RedirectToActionResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<RedirectToRouteResult>, RedirectToRouteResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<RedirectToPageResult>, RedirectToPageResultExecutor>();
+            services.TryAddSingleton<IActionResultExecutor<ContentResult>, ContentResultExecutor>();
 
             //
             // Route Handlers

src/Microsoft.AspNetCore.Mvc.Core/FileContentResult.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc.Infrastructure;
 using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Net.Http.Headers;

src/Microsoft.AspNetCore.Mvc.Core/FileStreamResult.cs

@@ -4,6 +4,7 @@
 using System;
 using System.IO;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc.Infrastructure;
 using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Net.Http.Headers;

src/Microsoft.AspNetCore.Mvc.Core/Internal/ContentResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/ContentResultExecutor.cs

@@ -4,11 +4,12 @@
 using System;
 using System.Text;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.Extensions.Logging;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
-    public class ContentResultExecutor
+    public class ContentResultExecutor : IActionResultExecutor<ContentResult>
     {
         private const string DefaultContentType = "text/plain; charset=utf-8";
         private readonly ILogger<ContentResultExecutor> _logger;
@@ -20,6 +21,7 @@ public ContentResultExecutor(ILogger<ContentResultExecutor> logger, IHttpRespons
             _httpResponseStreamWriterFactory = httpResponseStreamWriterFactory;
         }
 
+        /// <inheritdoc />
         public virtual async Task ExecuteAsync(ActionContext context, ContentResult result)
         {
             if (context == null)

src/Microsoft.AspNetCore.Mvc.Core/Internal/FileContentResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/FileContentResultExecutor.cs

@@ -7,15 +7,16 @@
 using Microsoft.Extensions.Logging;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
-    public class FileContentResultExecutor : FileResultExecutorBase
+    public class FileContentResultExecutor : FileResultExecutorBase, IActionResultExecutor<FileContentResult>
     {
         public FileContentResultExecutor(ILoggerFactory loggerFactory)
             : base(CreateLogger<FileContentResultExecutor>(loggerFactory))
         {
         }
 
+        /// <inheritdoc />
         public virtual Task ExecuteAsync(ActionContext context, FileContentResult result)
         {
             if (context == null)

src/Microsoft.AspNetCore.Mvc.Core/Internal/FileResultExecutorBase.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/FileResultExecutorBase.cs

@@ -10,10 +10,11 @@
 using Microsoft.AspNetCore.Http.Extensions;
 using Microsoft.AspNetCore.Http.Headers;
 using Microsoft.AspNetCore.Internal;
+using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.Extensions.Logging;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
     public class FileResultExecutorBase
     {

src/Microsoft.AspNetCore.Mvc.Core/Internal/FileStreamResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/FileStreamResultExecutor.cs

@@ -6,15 +6,16 @@
 using Microsoft.Extensions.Logging;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
-    public class FileStreamResultExecutor : FileResultExecutorBase
+    public class FileStreamResultExecutor : FileResultExecutorBase, IActionResultExecutor<FileStreamResult>
     {
         public FileStreamResultExecutor(ILoggerFactory loggerFactory)
             : base(CreateLogger<FileStreamResultExecutor>(loggerFactory))
         {
         }
 
+        /// <inheritdoc />
         public virtual Task ExecuteAsync(ActionContext context, FileStreamResult result)
         {
             if (context == null)

src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/IActionResultExecutor.cs

@@ -0,0 +1,29 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
+
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
+{
+    /// <summary>
+    /// Defines an interface for a service which can execute a particular kind of <see cref="IActionResult"/> by
+    /// manipulating the <see cref="HttpResponse"/>.
+    /// </summary>
+    /// <typeparam name="TResult">The type of <see cref="IActionResult"/>.</typeparam>
+    /// <remarks>
+    /// Implementions of <see cref="IActionResultExecutor{TResult}"/> are typically called by the
+    /// <see cref="IActionResult.ExecuteResultAsync(ActionContext)"/> method of the corresponding action result type.
+    /// Implementations should be registered as singleton services.
+    /// </remarks>
+    public interface IActionResultExecutor<in TResult> where TResult : IActionResult
+    {
+        /// <summary>
+        /// Asynchronously excecutes the action result, by modifying the <see cref="HttpResponse"/>.
+        /// </summary>
+        /// <param name="context">The <see cref="ActionContext"/> associated with the current request."/></param>
+        /// <param name="result">The action result to execute.</param>
+        /// <returns>A <see cref="Task"/> which represents the asynchronous operation.</returns>
+        Task ExecuteAsync(ActionContext context, TResult result);
+    }
+}

src/Microsoft.AspNetCore.Mvc.Core/Internal/LocalRedirectResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/LocalRedirectResultExecutor.cs

@@ -2,15 +2,17 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc.Core;
+using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.AspNetCore.Mvc.Routing;
 using Microsoft.Extensions.Logging;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
-    public class LocalRedirectResultExecutor
+    public class LocalRedirectResultExecutor : IActionResultExecutor<LocalRedirectResult>
     {
         private readonly ILogger _logger;
         private readonly IUrlHelperFactory _urlHelperFactory;
@@ -31,7 +33,8 @@ public LocalRedirectResultExecutor(ILoggerFactory loggerFactory, IUrlHelperFacto
             _urlHelperFactory = urlHelperFactory;
         }
 
-        public virtual void Execute(ActionContext context, LocalRedirectResult result)
+        /// <inheritdoc />
+        public virtual Task ExecuteAsync(ActionContext context, LocalRedirectResult result)
         {
             if (context == null)
             {
@@ -64,6 +67,8 @@ public virtual void Execute(ActionContext context, LocalRedirectResult result)
             {
                 context.HttpContext.Response.Redirect(destinationUrl, result.Permanent);
             }
+
+            return Task.CompletedTask;
         }
     }
 }

src/Microsoft.AspNetCore.Mvc.Core/Internal/ObjectResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/ObjectResultExecutor.cs

@@ -11,17 +11,18 @@
 using Microsoft.AspNetCore.Mvc.Core;
 using Microsoft.AspNetCore.Mvc.Formatters;
 using Microsoft.AspNetCore.Mvc.Formatters.Internal;
+using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Microsoft.Extensions.Primitives;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
     /// <summary>
     /// Executes an <see cref="ObjectResult"/> to write to the response.
     /// </summary>
-    public class ObjectResultExecutor
+    public class ObjectResultExecutor : IActionResultExecutor<ObjectResult>
     {
         /// <summary>
         /// Creates a new <see cref="ObjectResultExecutor"/>.

src/Microsoft.AspNetCore.Mvc.Core/Internal/PhysicalFileResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/PhysicalFileResultExecutor.cs

@@ -10,15 +10,16 @@
 using Microsoft.Extensions.Logging;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
-    public class PhysicalFileResultExecutor : FileResultExecutorBase
+    public class PhysicalFileResultExecutor : FileResultExecutorBase, IActionResultExecutor<PhysicalFileResult>
     {
         public PhysicalFileResultExecutor(ILoggerFactory loggerFactory)
             : base(CreateLogger<PhysicalFileResultExecutor>(loggerFactory))
         {
         }
 
+        /// <inheritdoc />
         public virtual Task ExecuteAsync(ActionContext context, PhysicalFileResult result)
         {
             if (context == null)

src/Microsoft.AspNetCore.Mvc.Core/Internal/RedirectResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/RedirectResultExecutor.cs

@@ -2,14 +2,16 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.AspNetCore.Mvc.Routing;
 using Microsoft.Extensions.Logging;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
-    public class RedirectResultExecutor
+    public class RedirectResultExecutor : IActionResultExecutor<RedirectResult>
     {
         private readonly ILogger _logger;
         private readonly IUrlHelperFactory _urlHelperFactory;
@@ -30,7 +32,8 @@ public RedirectResultExecutor(ILoggerFactory loggerFactory, IUrlHelperFactory ur
             _urlHelperFactory = urlHelperFactory;
         }
 
-        public virtual void Execute(ActionContext context, RedirectResult result)
+        /// <inheritdoc />
+        public virtual Task ExecuteAsync(ActionContext context, RedirectResult result)
         {
             if (context == null)
             {
@@ -63,6 +66,8 @@ public virtual void Execute(ActionContext context, RedirectResult result)
             {
                 context.HttpContext.Response.Redirect(destinationUrl, result.Permanent);
             }
+
+            return Task.CompletedTask;
         }
     }
 }

src/Microsoft.AspNetCore.Mvc.Core/Internal/RedirectToActionResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/RedirectToActionResultExecutor.cs

@@ -2,15 +2,17 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc.Core;
+using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.AspNetCore.Mvc.Routing;
 using Microsoft.Extensions.Logging;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
-    public class RedirectToActionResultExecutor
+    public class RedirectToActionResultExecutor : IActionResultExecutor<RedirectToActionResult>
     {
         private readonly ILogger _logger;
         private readonly IUrlHelperFactory _urlHelperFactory;
@@ -31,7 +33,8 @@ public RedirectToActionResultExecutor(ILoggerFactory loggerFactory, IUrlHelperFa
             _urlHelperFactory = urlHelperFactory;
         }
 
-        public virtual void Execute(ActionContext context, RedirectToActionResult result)
+        /// <inheritdoc />
+        public virtual Task ExecuteAsync(ActionContext context, RedirectToActionResult result)
         {
             if (context == null)
             {
@@ -69,6 +72,8 @@ public virtual void Execute(ActionContext context, RedirectToActionResult result
             {
                 context.HttpContext.Response.Redirect(destinationUrl, result.Permanent);
             }
+
+            return Task.CompletedTask;
         }
     }
 }

src/Microsoft.AspNetCore.Mvc.Core/Internal/RedirectToPageResultExecutor.cs renamed to src/Microsoft.AspNetCore.Mvc.Core/Infrastructure/RedirectToPageResultExecutor.cs

@@ -2,15 +2,17 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc.Core;
+using Microsoft.AspNetCore.Mvc.Internal;
 using Microsoft.AspNetCore.Mvc.Routing;
 using Microsoft.Extensions.Logging;
 using Microsoft.Net.Http.Headers;
 
-namespace Microsoft.AspNetCore.Mvc.Internal
+namespace Microsoft.AspNetCore.Mvc.Infrastructure
 {
-    public class RedirectToPageResultExecutor
+    public class RedirectToPageResultExecutor : IActionResultExecutor<RedirectToPageResult>
     {
         private readonly ILogger _logger;
         private readonly IUrlHelperFactory _urlHelperFactory;
@@ -31,7 +33,8 @@ public RedirectToPageResultExecutor(ILoggerFactory loggerFactory, IUrlHelperFact
             _urlHelperFactory = urlHelperFactory;
         }
 
-        public virtual void Execute(ActionContext context, RedirectToPageResult result)
+        /// <inheritdoc />
+        public virtual Task ExecuteAsync(ActionContext context, RedirectToPageResult result)
         {
             if (context == null)
             {
@@ -69,6 +72,8 @@ public virtual void Execute(ActionContext context, RedirectToPageResult result)
             {
                 context.HttpContext.Response.Redirect(destinationUrl, result.Permanent);
             }
+
+            return Task.CompletedTask;
         }
     }
 }