Don't automatically set Content-Length: 0 for HEAD requests and 304 r…

…esponses
aspnet · Aug 26, 2015 · ce5276e · ce5276e
1 parent 6975923
commit ce5276e
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Showing 2 changed files with 58 additions and 7 deletions.
diff --git a/src/Microsoft.AspNet.Server.Kestrel/Http/Frame.cs b/src/Microsoft.AspNet.Server.Kestrel/Http/Frame.cs
@@ -496,13 +496,16 @@ public void ProduceEnd(Exception ex)
 
             if (appCompleted && !hasTransferEncoding && !hasContentLength)
             {
-                // Since the app has completed and we are only now generating
-                // the headers we can safely set the Content-Length to 0.
-                writer.Write("Content-Length: 0\r\n");
-                hasContentLength = true;
+                // Don't set the Content-Length or Transfer-Encoding headers
+                // automatically for HEAD requests or 304 responses.
+                if (Method != "HEAD" && StatusCode != 304)
+                {
+                    // Since the app has completed and we are only now generating
+                    // the headers we can safely set the Content-Length to 0.
+                    writer.Write("Content-Length: 0\r\n");
+                }
             }
-
-            if (_keepAlive && !hasTransferEncoding && !hasContentLength)
+            else if (_keepAlive && !hasTransferEncoding && !hasContentLength)
             {
                 if (HttpVersion == "HTTP/1.1")
                 {
@@ -514,6 +517,7 @@ public void ProduceEnd(Exception ex)
                     _keepAlive = false;
                 }
             }
+
             if (_keepAlive == false && hasConnection == false && HttpVersion == "HTTP/1.1")
             {
                 writer.Write("Connection: close\r\n\r\n");

diff --git a/test/Microsoft.AspNet.Server.KestrelTests/EngineTests.cs b/test/Microsoft.AspNet.Server.KestrelTests/EngineTests.cs
@@ -377,7 +377,7 @@ public async Task DisconnectingClient()
         }
 
         [Fact]
-        public async Task EmptyResponseBodyHandledCorrectlyWithoutAnyWrites()
+        public async Task ZeroContentLengthSetAutomaticallyAfterNoWrites()
         {
             using (var server = new TestServer(frame =>
             {
@@ -400,6 +400,53 @@ public async Task EmptyResponseBodyHandledCorrectlyWithoutAnyWrites()
             }
         }
 
+        [Fact]
+        public async Task ZeroContentLengthNotSetAutomaticallyForHeadRequests()
+        {
+            using (var server = new TestServer(frame =>
+            {
+                frame.ResponseHeaders.Clear();
+                return Task.FromResult<object>(null);
+            }))
+            {
+                using (var connection = new TestConnection())
+                {
+                    await connection.SendEnd(
+                        "HEAD / HTTP/1.1",
+                        "",
+                        "");
+                    await connection.ReceiveEnd(
+                        "HTTP/1.1 200 OK",
+                        "",
+                        "");
+                }
+            }
+        }
+
+        [Fact]
+        public async Task ZeroContentLengthNotSetAutomaticallyFor304Responses()
+        {
+            using (var server = new TestServer(frame =>
+            {
+                frame.ResponseHeaders.Clear();
+                frame.StatusCode = 304;
+                return Task.FromResult<object>(null);
+            }))
+            {
+                using (var connection = new TestConnection())
+                {
+                    await connection.SendEnd(
+                        "GET / HTTP/1.1",
+                        "",
+                        "");
+                    await connection.ReceiveEnd(
+                        "HTTP/1.1 304 Not Modified",
+                        "",
+                        "");
+                }
+            }
+        }
+
         [Fact]
         public async Task ThrowingResultsIn500Response()
         {