Promote SendFile extension methods to HttpResponse

src/Microsoft.AspNetCore.Http.Abstractions/HttpResponse.cs

@@ -3,7 +3,9 @@
 
 using System;
 using System.IO;
+using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.Extensions.FileProviders;
 
 namespace Microsoft.AspNetCore.Http
 {
@@ -103,5 +105,23 @@ public abstract class HttpResponse
         /// <param name="location">The URL to redirect the client to.</param>
         /// <param name="permanent"><c>True</c> if the redirect is permanent (301), otherwise <c>false</c> (302).</param>
         public abstract void Redirect(string location, bool permanent);
+
+        /// <summary>
+        /// Sends the given file using the SendFile extension.
+        /// </summary>
+        /// <param name="file">The file to send.</param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        public abstract Task SendFileAsync(IFileInfo file, CancellationToken cancellationToken = default(CancellationToken));
+
+        /// <summary>
+        /// Sends the given file using the SendFile extension.
+        /// </summary>
+        /// <param name="file">The file to send.</param>
+        /// <param name="offset">The offset in the file.</param>
+        /// <param name="count">The number of types to send, or null to send the remainder of the file.</param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        public abstract Task SendFileAsync(IFileInfo file, long offset, long? count, CancellationToken cancellationToken = default(CancellationToken));
     }
 }

src/Microsoft.AspNetCore.Http.Extensions/StreamCopyOperation.cs → src/Microsoft.AspNetCore.Http.Abstractions/StreamCopyOperation.cs

@@ -8,7 +8,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 
-namespace Microsoft.AspNetCore.Http.Extensions
+namespace Microsoft.AspNetCore.Http
 {
     // FYI: In most cases the source will be a FileStream and the destination will be to the network.
     public static class StreamCopyOperation

src/Microsoft.AspNetCore.Http.Abstractions/project.json

@@ -11,11 +11,13 @@
   },
   "dependencies": {
     "Microsoft.AspNetCore.Http.Features": "1.0.0-*",
+    "Microsoft.Extensions.FileProviders.Abstractions": "1.0.0-*",
     "Microsoft.Extensions.ActivatorUtilities.Sources": {
       "type": "build",
       "version": "1.0.0-*"
     },
-    "System.Text.Encodings.Web": "4.0.0-*"
+    "System.Text.Encodings.Web": "4.0.0-*",
+    "System.Buffers": "4.0.0-*"
   },
   "frameworks": {
     "net451": {
@@ -32,7 +34,8 @@
         "System.Net.WebSockets": "4.0.0-*",
         "System.Reflection.TypeExtensions": "4.1.0-*",
         "System.Runtime.InteropServices": "4.0.21-*",
-        "System.Security.Cryptography.X509Certificates": "4.0.0-*"
+        "System.Security.Cryptography.X509Certificates": "4.0.0-*",
+        "System.IO.FileSystem": "4.0.1-*"
       }
     }
   }

src/Microsoft.AspNetCore.Http.Extensions/project.json

@@ -11,15 +11,10 @@
   },
   "dependencies": {
     "Microsoft.AspNetCore.Http.Abstractions": "1.0.0-*",
-    "Microsoft.Net.Http.Headers": "1.0.0-*",
-    "System.Buffers": "4.0.0-*"
+    "Microsoft.Net.Http.Headers": "1.0.0-*"
   },
   "frameworks": {
     "net451": {},
-    "dotnet5.4": {
-      "dependencies": {
-        "System.IO.FileSystem": "4.0.1-*"
-      }
-    }
+    "dotnet5.4": { }
   }
 }

src/Microsoft.AspNetCore.Http/DefaultHttpResponse.cs

@@ -3,9 +3,11 @@
 
 using System;
 using System.IO;
+using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Http.Features.Internal;
+using Microsoft.Extensions.FileProviders;
 using Microsoft.Net.Http.Headers;
 
 namespace Microsoft.AspNetCore.Http.Internal
@@ -37,7 +39,6 @@ public virtual void Uninitialize()
 
         private IResponseCookiesFeature ResponseCookiesFeature =>
             _features.Fetch(ref _features.Cache.Cookies, f => new ResponseCookiesFeature(f));
-
 
         public override HttpContext HttpContext { get { return _context; } }
 
@@ -133,6 +134,91 @@ public override void Redirect(string location, bool permanent)
             Headers[HeaderNames.Location] = location;
         }
 
+        public override Task SendFileAsync(IFileInfo file, CancellationToken cancellationToken = default(CancellationToken))
+        {
+            if (file == null)
+            {
+                throw new ArgumentNullException(nameof(file));
+            }
+
+            return SendFileAsync(file, 0, null, cancellationToken);
+        }
+
+        /// <summary>
+        /// Sends the given file using the SendFile extension.
+        /// </summary>
+        /// <param name="file">The file to send.</param>
+        /// <param name="offset">The offset in the file.</param>
+        /// <param name="count">The number of types to send, or null to send the remainder of the file.</param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        public override async Task SendFileAsync(IFileInfo file, long offset, long? count, CancellationToken cancellationToken = default(CancellationToken))
+        {
+            if (file == null)
+            {
+                throw new ArgumentNullException(nameof(file));
+            }
+
+            if (string.IsNullOrEmpty(file.PhysicalPath))
+            {
+                using (var readStream = file.CreateReadStream())
+                {
+                    await SendFileAsync(Body, readStream, offset, count, cancellationToken);
+                    return;
+                }
+            }
+
+            var sendFile = HttpContext.Features.Get<IHttpSendFileFeature>();
+
+            if (sendFile == null)
+            {
+                await SendFileAsync(Body, file.PhysicalPath, offset, count, cancellationToken);
+                return;
+            }
+
+            await sendFile.SendFileAsync(file.PhysicalPath, offset, count, cancellationToken);
+        }
+
+        private static async Task SendFileAsync(Stream outputStream, string fileName, long offset, long? count, CancellationToken cancellationToken)
+        {
+            int bufferSize = 1024 * 16;
+
+            var fileStream = new FileStream(
+                fileName,
+                FileMode.Open,
+                FileAccess.Read,
+                FileShare.ReadWrite,
+                bufferSize: bufferSize,
+                options: FileOptions.Asynchronous | FileOptions.SequentialScan);
+
+            using (fileStream)
+            {
+                await SendFileAsync(outputStream, fileStream, offset, count, cancellationToken);
+            }
+        }
+
+        // Not safe for overlapped writes.
+        private static async Task SendFileAsync(Stream outputStream, Stream readStream, long offset, long? length, CancellationToken cancellationToken)
+        {
+            cancellationToken.ThrowIfCancellationRequested();
+
+            if (offset < 0 || offset > readStream.Length)
+            {
+                throw new ArgumentOutOfRangeException(nameof(offset), offset, string.Empty);
+            }
+
+            if (length.HasValue &&
+                (length.Value < 0 || length.Value > readStream.Length - offset))
+            {
+                throw new ArgumentOutOfRangeException(nameof(length), length, string.Empty);
+            }
+
+            readStream.Seek(offset, SeekOrigin.Begin); // TODO: What if !CanSeek?
+
+            await StreamCopyOperation.CopyToAsync(readStream, outputStream, length, cancellationToken);
+        }
+
+
         struct FeatureInterfaces
         {
             public IHttpResponseFeature Response;

test/Microsoft.AspNetCore.Http.Extensions.Tests/SendFileResponseExtensionsTests.cs → test/Microsoft.AspNetCore.Http.Abstractions.Tests/SendFileTests.cs

@@ -6,19 +6,13 @@
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Http.Internal;
+using Microsoft.Extensions.FileProviders;
 using Xunit;
 
-namespace Microsoft.AspNetCore.Http.Extensions.Tests
+namespace Microsoft.AspNetCore.Http.Tests
 {
-    public class SendFileResponseExtensionsTests
+    public class SendFileTests
     {
-        [Fact]
-        public Task SendFileWhenFileNotFoundThrows()
-        {
-            var response = new DefaultHttpContext().Response;
-            return Assert.ThrowsAsync<FileNotFoundException>(() => response.SendFileAsync("foo"));
-        }
-
         [Fact]
         public async Task SendFileWorks()
         {
@@ -27,7 +21,8 @@ public async Task SendFileWorks()
             var fakeFeature = new FakeSendFileFeature();
             context.Features.Set<IHttpSendFileFeature>(fakeFeature);
 
-            await response.SendFileAsync("bob", 1, 3, CancellationToken.None);
+            var fileInfo = new FakeFileInfo("bob");
+            await response.SendFileAsync(fileInfo, 1, 3, CancellationToken.None);
 
             Assert.Equal("bob", fakeFeature.name);
             Assert.Equal(1, fakeFeature.offset);
@@ -51,5 +46,28 @@ public Task SendFileAsync(string path, long offset, long? length, CancellationTo
                 return Task.FromResult(0);
             }
         }
+
+        private class FakeFileInfo : IFileInfo
+        {
+            public FakeFileInfo(string name, bool exists = true)
+            {
+                Name = name;
+                Exists = exists;
+            }
+
+            public Stream CreateReadStream() => new MemoryStream();
+
+            public bool Exists { get; }
+
+            public long Length => 0;
+
+            public string PhysicalPath => Name;
+
+            public string Name { get; }
+
+            public DateTimeOffset LastModified => DateTimeOffset.UtcNow;
+
+            public bool IsDirectory => false;
+        }
     }
 }