Reacting to Hosting changes

src/Microsoft.AspNet.Server.Kestrel/Http/Frame.cs

@@ -206,9 +206,10 @@ public async Task RequestProcessingAsync()
                         ResponseBody = new FrameResponseStream(this);
                         DuplexStream = new FrameDuplexStream(RequestBody, ResponseBody);
 
+                        var httpContext = HttpContextFactory.Create(this);
                         try
                         {
-                            await Application.Invoke(this).ConfigureAwait(false);
+                            await Application.Invoke(httpContext).ConfigureAwait(false);
                         }
                         catch (Exception ex)
                         {
@@ -227,6 +228,8 @@ public async Task RequestProcessingAsync()
 
                             await FireOnCompleted();
 
+                            HttpContextFactory.Dispose(httpContext);
+
                             await ProduceEnd();
 
                             while (await RequestBody.ReadAsync(_nullBuffer, 0, _nullBuffer.Length) != 0)

src/Microsoft.AspNet.Server.Kestrel/Http/Listener.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Threading.Tasks;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Server.Kestrel.Networking;
 using Microsoft.Extensions.Logging;
 
@@ -23,7 +24,7 @@ protected Listener(ServiceContext serviceContext)
         public Task StartAsync(
             ServerAddress address,
             KestrelThread thread,
-            Func<Frame, Task> application)
+            RequestDelegate application)
         {
             ServerAddress = address;
             Thread = thread;

src/Microsoft.AspNet.Server.Kestrel/Http/ListenerContext.cs

@@ -1,8 +1,7 @@
 // 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;
-using System.Threading.Tasks;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Server.Kestrel.Infrastructure;
 
 namespace Microsoft.AspNet.Server.Kestrel.Http
@@ -34,7 +33,7 @@ public ListenerContext(ListenerContext listenerContext)
 
         public KestrelThread Thread { get; set; }
 
-        public Func<Frame, Task> Application { get; set; }
+        public RequestDelegate Application { get; set; }
 
         public MemoryPool2 Memory2 { get; set; }
     }

src/Microsoft.AspNet.Server.Kestrel/Http/ListenerPrimary.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Server.Kestrel.Infrastructure;
 using Microsoft.AspNet.Server.Kestrel.Networking;
 using Microsoft.Extensions.Logging;
@@ -33,7 +34,7 @@ public async Task StartAsync(
             string pipeName,
             ServerAddress address,
             KestrelThread thread,
-            Func<Frame, Task> application)
+            RequestDelegate application)
         {
             await StartAsync(address, thread, application).ConfigureAwait(false);
 

src/Microsoft.AspNet.Server.Kestrel/Http/ListenerSecondary.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Runtime.InteropServices;
 using System.Threading.Tasks;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Server.Kestrel.Infrastructure;
 using Microsoft.AspNet.Server.Kestrel.Networking;
 using Microsoft.Extensions.Logging;
@@ -26,7 +27,7 @@ public Task StartAsync(
             string pipeName,
             ServerAddress address,
             KestrelThread thread,
-            Func<Frame, Task> application)
+            RequestDelegate application)
         {
             ServerAddress = address;
             Thread = thread;

src/Microsoft.AspNet.Server.Kestrel/KestrelEngine.cs

@@ -3,8 +3,7 @@
 
 using System;
 using System.Collections.Generic;
-using System.Threading.Tasks;
-using Microsoft.AspNet.Http.Features;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Server.Kestrel.Http;
 using Microsoft.AspNet.Server.Kestrel.Networking;
 
@@ -49,7 +48,7 @@ public void Dispose()
             Threads.Clear();
         }
 
-        public IDisposable CreateServer(ServerAddress address, Func<IFeatureCollection, Task> application)
+        public IDisposable CreateServer(ServerAddress address, RequestDelegate application)
         {
             var listeners = new List<IDisposable>();
 

src/Microsoft.AspNet.Server.Kestrel/KestrelServer.cs

@@ -0,0 +1,128 @@
+// 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;
+using System.Collections.Generic;
+using Microsoft.AspNet.Hosting;
+using Microsoft.AspNet.Hosting.Server;
+using Microsoft.AspNet.Http;
+using Microsoft.AspNet.Http.Features;
+using Microsoft.AspNet.Server.Kestrel.Http;
+using Microsoft.Extensions.Logging;
+
+namespace Microsoft.AspNet.Server.Kestrel
+{
+    public class KestrelServer : IServer
+    {
+        private Stack<IDisposable> _disposables;
+        private readonly IApplicationLifetime _applicationLifetime;
+        private readonly ILogger _logger;
+        private readonly IHttpContextFactory _httpContextFactory;
+
+        public KestrelServer(IFeatureCollection features, IApplicationLifetime applicationLifetime, ILogger logger, IHttpContextFactory httpContextFactory)
+        {
+            if (features == null)
+            {
+                throw new ArgumentNullException(nameof(features));
+            }
+
+            if (applicationLifetime == null)
+            {
+                throw new ArgumentNullException(nameof(applicationLifetime));
+            }
+
+            if (logger == null)
+            {
+                throw new ArgumentNullException(nameof(logger));
+            }
+
+            if (httpContextFactory == null)
+            {
+                throw new ArgumentNullException(nameof(httpContextFactory));
+            }
+
+            _applicationLifetime = applicationLifetime;
+            _logger = logger;
+            Features = features;
+            _httpContextFactory = httpContextFactory;
+        }
+
+        public IFeatureCollection Features { get; }
+
+        public void Start(RequestDelegate requestDelegate)
+        {
+            if (_disposables != null)
+            {
+                // The server has already started and/or has not been cleaned up yet
+                throw new InvalidOperationException("Server has already started.");
+            }
+            _disposables = new Stack<IDisposable>();
+
+            try
+            {
+                var information = (KestrelServerInformation)Features.Get<IKestrelServerInformation>();
+                var dateHeaderValueManager = new DateHeaderValueManager();
+                var engine = new KestrelEngine(new ServiceContext
+                {
+                    AppLifetime = _applicationLifetime,
+                    Log = new KestrelTrace(_logger),
+                    HttpContextFactory = _httpContextFactory,
+                    DateHeaderValueManager = dateHeaderValueManager,
+                    ConnectionFilter = information.ConnectionFilter,
+                    NoDelay = information.NoDelay
+                });
+
+                _disposables.Push(engine);
+                _disposables.Push(dateHeaderValueManager);
+
+                if (information.ThreadCount < 0)
+                {
+                    throw new ArgumentOutOfRangeException(nameof(information.ThreadCount),
+                        information.ThreadCount,
+                        "ThreadCount cannot be negative");
+                }
+
+                engine.Start(information.ThreadCount == 0 ? 1 : information.ThreadCount);
+                var atLeastOneListener = false;
+
+                foreach (var address in information.Addresses)
+                {
+                    var parsedAddress = ServerAddress.FromUrl(address);
+                    if (parsedAddress == null)
+                    {
+                        throw new FormatException("Unrecognized listening address: " + address);
+                    }
+                    else
+                    {
+                        atLeastOneListener = true;
+                        _disposables.Push(engine.CreateServer(
+                            parsedAddress,
+                            requestDelegate));
+                    }
+                }
+
+                if (!atLeastOneListener)
+                {
+                    throw new InvalidOperationException("No recognized listening addresses were configured.");
+                }
+            }
+            catch
+            {
+                Dispose();
+                throw;
+            }
+        }
+
+        public void Dispose()
+        {
+            if (_disposables != null)
+            {
+                while (_disposables.Count > 0)
+                {
+                    _disposables.Pop().Dispose();
+                }
+                _disposables = null;
+            }
+        }
+    }
+}

src/Microsoft.AspNet.Server.Kestrel/ServerFactory.cs

@@ -1,14 +1,11 @@
 // 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;
-using System.Collections.Generic;
-using System.Threading.Tasks;
 using Microsoft.AspNet.Hosting;
 using Microsoft.AspNet.Hosting.Server;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Http.Features;
 using Microsoft.AspNet.Server.Features;
-using Microsoft.AspNet.Server.Kestrel.Http;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Logging;
 
@@ -20,89 +17,24 @@ namespace Microsoft.AspNet.Server.Kestrel
     public class ServerFactory : IServerFactory
     {
         private readonly IApplicationLifetime _appLifetime;
-        private readonly ILogger _logger;
+        private readonly ILoggerFactory _loggerFactory;
+        private readonly IHttpContextFactory _httpContextFactory;
 
-        public ServerFactory(IApplicationLifetime appLifetime, ILoggerFactory loggerFactory)
+        public ServerFactory(IApplicationLifetime appLifetime, ILoggerFactory loggerFactory, IHttpContextFactory httpContextFactory)
         {
             _appLifetime = appLifetime;
-            _logger = loggerFactory.CreateLogger("Microsoft.AspNet.Server.Kestrel");
+            _loggerFactory = loggerFactory;
+            _httpContextFactory = httpContextFactory;
         }
 
-        public IFeatureCollection Initialize(IConfiguration configuration)
+        public IServer CreateServer(IConfiguration configuration)
         {
             var information = new KestrelServerInformation();
             information.Initialize(configuration);
             var serverFeatures = new FeatureCollection();
             serverFeatures.Set<IKestrelServerInformation>(information);
             serverFeatures.Set<IServerAddressesFeature>(information);
-            return serverFeatures;
-        }
-
-        public IDisposable Start(IFeatureCollection serverFeatures, Func<IFeatureCollection, Task> application)
-        {
-            var disposables = new Stack<IDisposable>();
-            var disposer = new Disposable(() =>
-            {
-                foreach (var disposable in disposables)
-                {
-                    disposable.Dispose();
-                }
-            });
-
-            try
-            {
-                var information = (KestrelServerInformation)serverFeatures.Get<IKestrelServerInformation>();
-                var dateHeaderValueManager = new DateHeaderValueManager();
-                var engine = new KestrelEngine(new ServiceContext
-                {
-                    AppLifetime = _appLifetime,
-                    Log = new KestrelTrace(_logger),
-                    DateHeaderValueManager = dateHeaderValueManager,
-                    ConnectionFilter = information.ConnectionFilter,
-                    NoDelay = information.NoDelay
-                });
-
-                disposables.Push(engine);
-                disposables.Push(dateHeaderValueManager);
-
-                if (information.ThreadCount < 0)
-                {
-                    throw new ArgumentOutOfRangeException(nameof(information.ThreadCount),
-                        information.ThreadCount,
-                        "ThreadCount cannot be negative");
-                }
-
-                engine.Start(information.ThreadCount == 0 ? 1 : information.ThreadCount);
-                bool atLeastOneListener = false;
-
-                foreach (var address in information.Addresses)
-                {
-                    var parsedAddress = ServerAddress.FromUrl(address);
-                    if (parsedAddress == null)
-                    {
-                        throw new FormatException("Unrecognized listening address: " + address);
-                    }
-                    else
-                    {
-                        atLeastOneListener = true;
-                        disposables.Push(engine.CreateServer(
-                            parsedAddress,
-                            application));
-                    }
-                }
-
-                if (!atLeastOneListener)
-                {
-                    throw new InvalidOperationException("No recognized listening addresses were configured.");
-                }
-
-                return disposer;
-            }
-            catch
-            {
-                disposer.Dispose();
-                throw;
-            }
+            return new KestrelServer(serverFeatures, _appLifetime, _loggerFactory.CreateLogger("Microsoft.AspNet.Server.Kestrel"), _httpContextFactory);
         }
     }
 }

src/Microsoft.AspNet.Server.Kestrel/ServiceContext.cs

@@ -2,6 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using Microsoft.AspNet.Hosting;
+using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Server.Kestrel.Filter;
 using Microsoft.AspNet.Server.Kestrel.Http;
 using Microsoft.AspNet.Server.Kestrel.Infrastructure;
@@ -20,6 +21,7 @@ public ServiceContext(ServiceContext context)
             AppLifetime = context.AppLifetime;
             Memory = context.Memory;
             Log = context.Log;
+            HttpContextFactory = context.HttpContextFactory;
             DateHeaderValueManager = context.DateHeaderValueManager;
             ConnectionFilter = context.ConnectionFilter;
             NoDelay = context.NoDelay;
@@ -31,6 +33,8 @@ public ServiceContext(ServiceContext context)
 
         public IKestrelTrace Log { get; set; }
 
+        public IHttpContextFactory HttpContextFactory { get; set; }
+
         public DateHeaderValueManager DateHeaderValueManager { get; set; }
 
         public IConnectionFilter ConnectionFilter { get; set; }

test/Microsoft.AspNet.Server.Kestrel.FunctionalTests/AddressRegistrationTests.cs

@@ -26,7 +26,7 @@ public async Task RegisterAddresses_Success(string addressInput, string[] testUr
                 .Build();
 
             var hostBuilder = new WebHostBuilder(config);
-            hostBuilder.UseServer("Microsoft.AspNet.Server.Kestrel");
+            hostBuilder.UseServerFactory("Microsoft.AspNet.Server.Kestrel");
             hostBuilder.UseStartup(ConfigureEchoAddress);            
 
             using (var app = hostBuilder.Build().Start())

test/Microsoft.AspNet.Server.Kestrel.FunctionalTests/RequestTests.cs

@@ -28,7 +28,7 @@ public async Task LargeUpload()
                 .Build();
 
             var hostBuilder = new WebHostBuilder(config);
-            hostBuilder.UseServer("Microsoft.AspNet.Server.Kestrel");
+            hostBuilder.UseServerFactory("Microsoft.AspNet.Server.Kestrel");
             hostBuilder.UseStartup(app =>
             {
                 app.Run(async context =>