Adding abstractions for request headers

viz. Accept, Accept-Charset and Content-Type.

HttpAbstractions.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 14
-VisualStudioVersion = 14.0.21813.0
+VisualStudioVersion = 14.0.21806.0
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "src", "src", "{A5A15F1C-885A-452A-A731-B0173DDBD913}"
 EndProject

src/Microsoft.AspNet.Http/HttpRequest.cs

@@ -2,6 +2,8 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Collections;
+using System.Collections.Generic;
 using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
@@ -95,7 +97,7 @@ namespace Microsoft.AspNet.Http
         /// Gets or sets the Content-Type header.
         /// </summary>
         /// <returns>The Content-Type header.</returns>
-        // (TODO header conventions?) public abstract string ContentType { get; set; }
+        public abstract string ContentType { get; set; }
 
         /// <summary>
         /// Gets or sets the Cache-Control header.
@@ -113,7 +115,13 @@ namespace Microsoft.AspNet.Http
         /// Gets or set the Accept header.
         /// </summary>
         /// <returns>The Accept header.</returns>
-        // (TODO header conventions?) public abstract string Accept { get; set; }
+        public abstract string Accept { get; set; }
+
+        /// <summary>
+        /// Gets or set the Accept-Charset header.
+        /// </summary>
+        /// <returns>The Accept-Charset header.</returns>
+        public abstract string AcceptCharset { get; set; }
 
         /// <summary>
         /// Gets or set the owin.RequestBody Stream.

src/Microsoft.AspNet.PipelineCore/DefaultHttpRequest.cs

@@ -149,5 +149,23 @@ namespace Microsoft.AspNet.PipelineCore
         {
             get { return RequestCookiesFeature.Cookies; }
         }
+
+        public override string ContentType
+        {
+            get { return Headers[Constants.Headers.ContentType]; }
+            set { Headers[Constants.Headers.ContentType] = value; }
+        }
+
+        public override string Accept
+        {
+            get { return Headers[Constants.Headers.Accept]; }
+            set { Headers[Constants.Headers.Accept] = value; }
+        }
+
+        public override string AcceptCharset
+        {
+            get { return Headers[Constants.Headers.AcceptCharset]; }
+            set { Headers[Constants.Headers.AcceptCharset] = value; }
+        }
     }
 }

src/Microsoft.AspNet.PipelineCore/Infrastructure/Constants.cs

@@ -15,6 +15,7 @@ namespace Microsoft.AspNet.Http.Infrastructure
             internal const string CacheControl = "Cache-Control";
             internal const string MediaType = "Media-Type";
             internal const string Accept = "Accept";
+            internal const string AcceptCharset = "Accept-Charset";
             internal const string Host = "Host";
             internal const string ETag = "ETag";
             internal const string Location = "Location";

test/Microsoft.AspNet.PipelineCore.Tests/DefaultHttpRequestTests.cs

@@ -49,6 +49,36 @@ namespace Microsoft.AspNet.PipelineCore.Tests
             Assert.Null(request.ContentLength);
         }
 
+        [Fact]
+        public void GetContentType_ReturnsNullIfHeaderDoesNotExist()
+        {
+            // Arrange
+            var request = GetRequestWithContentType(contentType: null);
+
+            // Act and Assert
+            Assert.Null(request.ContentType);
+        }
+
+        [Fact]
+        public void GetAcceptHeader_ReturnsNullIfHeaderDoesNotExist()
+        {
+            // Arrange
+            var request = GetRequestWithAcceptHeader(acceptHeader: null);
+
+            // Act and Assert
+            Assert.Null(request.Accept);
+        }
+
+        [Fact]
+        public void GetAcceptCharsetHeader_ReturnsNullIfHeaderDoesNotExist()
+        {
+            // Arrange
+            var request = GetRequestWithAcceptCharsetHeader(acceptCharset: null);
+
+            // Act and Assert
+            Assert.Null(request.AcceptCharset);
+        }
+
         [Fact]
         public void Host_GetsHostFromHeaders()
         {
@@ -114,14 +144,34 @@ namespace Microsoft.AspNet.PipelineCore.Tests
         }
 
         private static HttpRequest GetRequestWithContentLength(string contentLength = null)
+        {
+            return GetRequestWithHeader("Content-Length", contentLength);
+        }
+
+        private static HttpRequest GetRequestWithContentType(string contentType = null)
+        {
+            return GetRequestWithHeader("Content-Type", contentType);
+        }
+
+        private static HttpRequest GetRequestWithAcceptHeader(string acceptHeader = null)
+        {
+            return GetRequestWithHeader("Accept", acceptHeader);
+        }
+
+        private static HttpRequest GetRequestWithAcceptCharsetHeader(string acceptCharset = null)
+        {
+            return GetRequestWithHeader("Accept-Charset", acceptCharset);
+        }
+
+        private static HttpRequest GetRequestWithHeader(string headerName, string headerValue)
         {
             var headers = new Dictionary<string, string[]>(StringComparer.OrdinalIgnoreCase);
-            if (contentLength != null)
+            if (headerValue != null)
             {
-                headers.Add("Content-Length", new[] { contentLength });
+                headers.Add(headerName, new[] { headerValue });
             }
 
- 		    return CreateRequest(headers);
+            return CreateRequest(headers);
         }
     }
 }