Reset Frame's IHttpRequestFeature.Headers and IHttpResponseFeature.Headers between requests (#879).

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

@@ -11,7 +11,6 @@ using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
-using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Server.Kestrel.Infrastructure;
 using Microsoft.AspNetCore.Server.Kestrel.Exceptions;
 using Microsoft.Extensions.Logging;
@@ -217,13 +216,17 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Http
         {
             if (FrameRequestHeaders == null)
             {
-                RequestHeaders = FrameRequestHeaders = new FrameRequestHeaders();
+                FrameRequestHeaders = new FrameRequestHeaders();
             }
 
+            RequestHeaders = FrameRequestHeaders;
+
             if (FrameResponseHeaders == null)
             {
-                ResponseHeaders = FrameResponseHeaders = new FrameResponseHeaders();
+                FrameResponseHeaders = new FrameResponseHeaders();
             }
+
+            ResponseHeaders = FrameResponseHeaders;
         }
 
         public void InitializeStreams(MessageBody messageBody)
@@ -646,8 +649,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Http
                 {
                     responseHeaders.SetRawServer(Constants.ServerName, _bytesServer);
                 }
-
-                ResponseHeaders = responseHeaders;
             }
 
             if (!HasResponseStarted)

test/Microsoft.AspNetCore.Server.KestrelTests/EngineTests.cs

@@ -11,6 +11,7 @@ using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Server.Kestrel;
+using Microsoft.AspNetCore.Server.Kestrel.Http;
 using Microsoft.AspNetCore.Server.Kestrel.Infrastructure;
 using Xunit;
 
@@ -1057,9 +1058,6 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
         [MemberData(nameof(ConnectionFilterData))]
         public async Task NoResponseSentWhenConnectionIsClosedByServerBeforeClientFinishesSendingRequest(TestServiceContext testContext)
         {
-            var testLogger = new TestApplicationErrorLogger();
-            testContext.Log = new KestrelTrace(testLogger);
-
             using (var server = new TestServer(httpContext =>
             {
                 httpContext.Abort();
@@ -1077,5 +1075,99 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
                 }
             }
         }
+
+        [Theory]
+        [MemberData(nameof(ConnectionFilterData))]
+        public async Task RequestHeadersAreResetOnEachRequest(TestServiceContext testContext)
+        {
+            IHeaderDictionary originalRequestHeaders = null;
+            var firstRequest = true;
+
+            using (var server = new TestServer(httpContext =>
+            {
+                var requestFeature = httpContext.Features.Get<IHttpRequestFeature>();
+
+                if (firstRequest)
+                {
+                    originalRequestHeaders = requestFeature.Headers;
+                    requestFeature.Headers = new FrameRequestHeaders();
+                    firstRequest = false;
+                }
+                else
+                {
+                    Assert.Same(originalRequestHeaders, requestFeature.Headers);
+                }
+
+                return TaskUtilities.CompletedTask;
+            }, testContext))
+            {
+                using (var connection = server.CreateConnection())
+                {
+                    await connection.SendEnd(
+                        "GET / HTTP/1.1",
+                        "",
+                        "GET / HTTP/1.1",
+                        "",
+                        "");
+                    await connection.ReceiveEnd(
+                        "HTTP/1.1 200 OK",
+                        $"Date: {testContext.DateHeaderValue}",
+                        "Content-Length: 0",
+                        "",
+                        "HTTP/1.1 200 OK",
+                        $"Date: {testContext.DateHeaderValue}",
+                        "Content-Length: 0",
+                        "",
+                        "");
+                }
+            }
+        }
+
+        [Theory]
+        [MemberData(nameof(ConnectionFilterData))]
+        public async Task ResponseHeadersAreResetOnEachRequest(TestServiceContext testContext)
+        {
+            IHeaderDictionary originalResponseHeaders = null;
+            var firstRequest = true;
+
+            using (var server = new TestServer(httpContext =>
+            {
+                var responseFeature = httpContext.Features.Get<IHttpResponseFeature>();
+
+                if (firstRequest)
+                {
+                    originalResponseHeaders = responseFeature.Headers;
+                    responseFeature.Headers = new FrameResponseHeaders();
+                    firstRequest = false;
+                }
+                else
+                {
+                    Assert.Same(originalResponseHeaders, responseFeature.Headers);
+                }
+
+                return TaskUtilities.CompletedTask;
+            }, testContext))
+            {
+                using (var connection = server.CreateConnection())
+                {
+                    await connection.SendEnd(
+                        "GET / HTTP/1.1",
+                        "",
+                        "GET / HTTP/1.1",
+                        "",
+                        "");
+                    await connection.ReceiveEnd(
+                        "HTTP/1.1 200 OK",
+                        $"Date: {testContext.DateHeaderValue}",
+                        "Content-Length: 0",
+                        "",
+                        "HTTP/1.1 200 OK",
+                        $"Date: {testContext.DateHeaderValue}",
+                        "Content-Length: 0",
+                        "",
+                        "");
+                }
+            }
+        }
     }
 }

test/Microsoft.AspNetCore.Server.KestrelTests/FrameTests.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Linq;
 using System.Text;
+using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Server.Kestrel;
 using Microsoft.AspNetCore.Server.Kestrel.Http;
@@ -115,5 +116,51 @@ namespace Microsoft.AspNetCore.Server.KestrelTests
             Assert.True(frame.HasResponseStarted);
             Assert.Throws<InvalidOperationException>(() => ((IHttpResponseFeature)frame).ReasonPhrase = "Reason phrase");
         }
+
+        [Fact]
+        public void InitializeHeadersResetsRequestHeaders()
+        {
+            // Arrange
+            var connectionContext = new ConnectionContext()
+            {
+                DateHeaderValueManager = new DateHeaderValueManager(),
+                ServerAddress = ServerAddress.FromUrl("http://localhost:5000"),
+                ServerOptions = new KestrelServerOptions(),
+                SocketOutput = new MockSocketOuptut()
+            };
+            var frame = new Frame<object>(application: null, context: connectionContext);
+            frame.InitializeHeaders();
+
+            // Act
+            var originalRequestHeaders = frame.RequestHeaders;
+            frame.RequestHeaders = new FrameRequestHeaders();
+            frame.InitializeHeaders();
+
+            // Assert
+            Assert.Same(originalRequestHeaders, frame.RequestHeaders);
+        }
+
+        [Fact]
+        public void InitializeHeadersResetsResponseHeaders()
+        {
+            // Arrange
+            var connectionContext = new ConnectionContext()
+            {
+                DateHeaderValueManager = new DateHeaderValueManager(),
+                ServerAddress = ServerAddress.FromUrl("http://localhost:5000"),
+                ServerOptions = new KestrelServerOptions(),
+                SocketOutput = new MockSocketOuptut()
+            };
+            var frame = new Frame<object>(application: null, context: connectionContext);
+            frame.InitializeHeaders();
+
+            // Act
+            var originalResponseHeaders = frame.ResponseHeaders;
+            frame.ResponseHeaders = new FrameResponseHeaders();
+            frame.InitializeHeaders();
+
+            // Assert
+            Assert.Same(originalResponseHeaders, frame.ResponseHeaders);
+        }
     }
 }