From 72a216625f16617579f0c0102a7d6624865148d6 Mon Sep 17 00:00:00 2001
From: Violeta Georgieva <milesg78@gmail.com>
Date: Fri, 10 Nov 2017 10:33:29 +0200
Subject: [PATCH] Correctly handle 205 Reset Content response with
 transfer-encoding

Motivation:

According to RFC 7231 the server may choose to:
```
indicate a zero-length payload for the response by including a
Transfer-Encoding header field with a value of chunked and a message
body consisting of a single chunk of zero-length
```
https://tools.ietf.org/html/rfc7231#page-53

In such cases the exception below appears during decoding phase:
```
java.lang.IllegalArgumentException: invalid version format: 0
	at io.netty.handler.codec.http.HttpVersion.<init>(HttpVersion.java:121)
	at io.netty.handler.codec.http.HttpVersion.valueOf(HttpVersion.java:76)
	at io.netty.handler.codec.http.HttpResponseDecoder.createMessage(HttpResponseDecoder.java:118)
	at io.netty.handler.codec.http.HttpObjectDecoder.decode(HttpObjectDecoder.java:219)
```

Modifications:

HttpObjectDecoder.isContentAlwaysEmpty specifies content NOT empty
when 205 Reset Content response

Result:

There is no `IllegalArgumentException: invalid version format: 0`
when handling 205 Reset Content response with transfer-encoding
---
 .../handler/codec/http/HttpObjectDecoder.java |  2 +-
 .../codec/http/HttpResponseDecoderTest.java   | 22 +++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java b/codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java
index 513d2aa415..22271d81d0 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java
@@ -477,7 +477,7 @@ public abstract class HttpObjectDecoder extends ByteToMessageDecoder {
             }
 
             switch (code) {
-            case 204: case 205: case 304:
+            case 204: case 304:
                 return true;
             }
         }
diff --git a/codec-http/src/test/java/io/netty/handler/codec/http/HttpResponseDecoderTest.java b/codec-http/src/test/java/io/netty/handler/codec/http/HttpResponseDecoderTest.java
index f346de91c9..017dbd5ff9 100644
--- a/codec-http/src/test/java/io/netty/handler/codec/http/HttpResponseDecoderTest.java
+++ b/codec-http/src/test/java/io/netty/handler/codec/http/HttpResponseDecoderTest.java
@@ -368,6 +368,28 @@ public class HttpResponseDecoderTest {
         assertThat(ch.readInbound(), is(nullValue()));
     }
 
+    @Test
+    public void testResetContentResponseWithTransferEncoding() {
+        EmbeddedChannel ch = new EmbeddedChannel(new HttpResponseDecoder());
+        assertTrue(ch.writeInbound(Unpooled.copiedBuffer(
+                "HTTP/1.1 205 Reset Content\r\n" +
+                "Transfer-Encoding: chunked\r\n" +
+                "\r\n" +
+                "0\r\n" +
+                "\r\n",
+                CharsetUtil.US_ASCII)));
+
+        HttpResponse res = ch.readInbound();
+        assertThat(res.protocolVersion(), sameInstance(HttpVersion.HTTP_1_1));
+        assertThat(res.status(), is(HttpResponseStatus.RESET_CONTENT));
+
+        LastHttpContent lastContent = ch.readInbound();
+        assertThat(lastContent.content().isReadable(), is(false));
+        lastContent.release();
+
+        assertThat(ch.finish(), is(false));
+    }
+
     @Test
     public void testLastResponseWithTrailingHeader() {
         EmbeddedChannel ch = new EmbeddedChannel(new HttpResponseDecoder());