Fix for issue #1281 - Add ModelBinder for HttpRequestMessage

This change adds a ModelBinder that can bind an HttpRequestMessage to an
action parameter.

This builds on an earlier change to construct and store the request
message in the HttpContext via an http feature.

src/Microsoft.AspNet.Mvc.WebApiCompatShim/HttpRequestMessage/HttpRequestMessageModelBinder.cs

@@ -0,0 +1,23 @@
+using Microsoft.AspNet.Mvc.ModelBinding;
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Net.Http;
+using System.Threading.Tasks;
+
+namespace Microsoft.AspNet.Mvc.WebApiCompatShim
+{
+    public class HttpRequestMessageModelBinder : IModelBinder
+    {
+        public Task<bool> BindModelAsync(ModelBindingContext bindingContext)
+        {
+            if (bindingContext.ModelType == typeof(HttpRequestMessage))
+            {
+                bindingContext.Model = bindingContext.HttpContext.GetHttpRequestMessage();
+                return Task.FromResult(true);
+            }
+
+            return Task.FromResult(false);
+        }
+    }
+}

src/Microsoft.AspNet.Mvc.WebApiCompatShim/WebApiCompatShimOptionsSetup.cs

@@ -21,6 +21,9 @@ namespace Microsoft.AspNet.Mvc.WebApiCompatShim
             // Add webapi behaviors to controllers with the appropriate attributes
             options.ApplicationModelConventions.Add(new WebApiActionConventionsGlobalModelConvention());
             options.ApplicationModelConventions.Add(new WebApiOverloadingGlobalModelConvention());
+
+            // Add a model binder to be able to bind HttpRequestMessage
+            options.ModelBinders.Insert(0, new HttpRequestMessageModelBinder());
         }
 
         public void Invoke(WebApiCompatShimOptions options)

test/Microsoft.AspNet.Mvc.FunctionalTests/WebApiCompatShimBasicTest.cs

@@ -101,6 +101,28 @@ namespace Microsoft.AspNet.Mvc.FunctionalTests
             Assert.Equal(HttpStatusCode.OK, response.StatusCode);
             Assert.Equal(expected, content);
         }
+
+        [Fact]
+        public async Task ApiController_RequestParameter()
+        { 
+            // Arrange
+            var server = TestServer.Create(_provider, _app);
+            var client = server.CreateClient();
+
+            var expected =
+                "POST http://localhost/api/Blog/HttpRequestMessage/EchoParameter localhost " +
+                "17 Hello, the world!";
+
+            // Act
+            var response = await client.PostAsync(
+                "http://localhost/api/Blog/HttpRequestMessage/EchoParameter",
+                new StringContent("Hello, the world!"));
+            var content = await response.Content.ReadAsStringAsync();
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            Assert.Equal(expected, content);
+        }
     }
 }
 #endif

test/WebSites/WebApiCompatShimWebSite/Controllers/HttpRequestMessage/HttpRequestMessageController.cs

@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
+using System.Net.Http;
 using System.Threading.Tasks;
 using System.Web.Http;
 using Microsoft.AspNet.Http;
@@ -12,18 +14,32 @@ namespace WebApiCompatShimWebSite
     {
         public async Task<IActionResult> EchoProperty()
         {
-            var request = Request;
+            await Echo(Request);
+            return new EmptyResult(); 
+        }
 
+        public async Task<IActionResult> EchoParameter(HttpRequestMessage request)
+        {
+            if (!object.ReferenceEquals(request, Request))
+            {
+                throw new InvalidOperationException();
+            }
+
+            await Echo(request);
+            return new EmptyResult();
+        }
+
+        private async Task Echo(HttpRequestMessage request)
+        {
             var message = string.Format(
                 "{0} {1} {2} {3} {4}",
-                request.Method, 
+                request.Method,
                 request.RequestUri.AbsoluteUri,
                 request.Headers.Host,
                 request.Content.Headers.ContentLength,
                 await request.Content.ReadAsStringAsync());
 
             await Context.Response.WriteAsync(message);
-            return new EmptyResult();
         }
     }
 }