Fixes #5103 - Proxy sets protocol version to 2.0 instead of 1.1 when accessed from H2 client.

Fixed by removing the explicit version copy.
Leaving it at default would make the client transport
decide the version based on the transport protocol it uses.

Signed-off-by: Simone Bordet <simone.bordet@gmail.com>

jetty-http2/http2-client/src/test/java/org/eclipse/jetty/http2/client/ProxyTest.java

@@ -24,15 +24,14 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
-import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-import org.eclipse.jetty.client.api.Request;
 import org.eclipse.jetty.http.HostPortHttpField;
 import org.eclipse.jetty.http.HttpFields;
 import org.eclipse.jetty.http.HttpScheme;
+import org.eclipse.jetty.http.HttpStatus;
 import org.eclipse.jetty.http.HttpVersion;
 import org.eclipse.jetty.http.MetaData;
 import org.eclipse.jetty.http2.api.Session;
@@ -53,6 +52,7 @@ import org.eclipse.jetty.util.thread.QueuedThreadPool;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 public class ProxyTest
@@ -137,14 +137,49 @@ public class ProxyTest
     }
 
     @Test
-    public void testServerBigDownloadSlowClient() throws Exception
+    public void testHTTPVersion() throws Exception
     {
-        final CountDownLatch serverLatch = new CountDownLatch(1);
-        final byte[] content = new byte[1024 * 1024];
         startServer(new HttpServlet()
         {
             @Override
-            protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
+            protected void service(HttpServletRequest request, HttpServletResponse response)
+            {
+                assertEquals(HttpVersion.HTTP_1_1.asString(), request.getProtocol());
+            }
+        });
+        Map<String, String> params = new HashMap<>();
+        params.put("proxyTo", "http://localhost:" + serverConnector.getLocalPort());
+        startProxy(new AsyncProxyServlet.Transparent(), params);
+        startClient();
+
+        CountDownLatch clientLatch = new CountDownLatch(1);
+        Session session = newClient(new Session.Listener.Adapter());
+        MetaData.Request metaData = newRequest("GET", "/", new HttpFields());
+        HeadersFrame frame = new HeadersFrame(metaData, null, true);
+        session.newStream(frame, new Promise.Adapter<>(), new Stream.Listener.Adapter()
+        {
+            @Override
+            public void onHeaders(Stream stream, HeadersFrame frame)
+            {
+                assertTrue(frame.isEndStream());
+                MetaData.Response response = (MetaData.Response)frame.getMetaData();
+                assertEquals(HttpStatus.OK_200, response.getStatus());
+                clientLatch.countDown();
+            }
+        });
+
+        assertTrue(clientLatch.await(5, TimeUnit.SECONDS));
+    }
+
+    @Test
+    public void testServerBigDownloadSlowClient() throws Exception
+    {
+        CountDownLatch serverLatch = new CountDownLatch(1);
+        byte[] content = new byte[1024 * 1024];
+        startServer(new HttpServlet()
+        {
+            @Override
+            protected void service(HttpServletRequest request, HttpServletResponse response) throws IOException
             {
                 response.getOutputStream().write(content);
                 serverLatch.countDown();
@@ -152,18 +187,10 @@ public class ProxyTest
         });
         Map<String, String> params = new HashMap<>();
         params.put("proxyTo", "http://localhost:" + serverConnector.getLocalPort());
-        startProxy(new AsyncProxyServlet.Transparent()
+        startProxy(new AsyncProxyServlet.Transparent(), params);
-        {
-            @Override
-            protected void sendProxyRequest(HttpServletRequest clientRequest, HttpServletResponse proxyResponse, Request proxyRequest)
-            {
-                proxyRequest.version(HttpVersion.HTTP_1_1);
-                super.sendProxyRequest(clientRequest, proxyResponse, proxyRequest);
-            }
-        }, params);
         startClient();
 
-        final CountDownLatch clientLatch = new CountDownLatch(1);
+        CountDownLatch clientLatch = new CountDownLatch(1);
         Session session = newClient(new Session.Listener.Adapter());
         MetaData.Request metaData = newRequest("GET", "/", new HttpFields());
         HeadersFrame frame = new HeadersFrame(metaData, null, true);

jetty-proxy/src/main/java/org/eclipse/jetty/proxy/AbstractProxyServlet.java

@@ -50,7 +50,6 @@ import org.eclipse.jetty.http.HttpField;
 import org.eclipse.jetty.http.HttpHeader;
 import org.eclipse.jetty.http.HttpHeaderValue;
 import org.eclipse.jetty.http.HttpStatus;
-import org.eclipse.jetty.http.HttpVersion;
 import org.eclipse.jetty.util.HttpCookieStore;
 import org.eclipse.jetty.util.ProcessorUtils;
 import org.eclipse.jetty.util.StringUtil;
@@ -457,9 +456,10 @@ public abstract class AbstractProxyServlet extends HttpServlet
 
     protected Request newProxyRequest(HttpServletRequest request, String rewrittenTarget)
     {
+        // Do not copy the HTTP version, since the client-to-proxy
+        // version may be different from the proxy-to-server version.
         return getHttpClient().newRequest(rewrittenTarget)
             .method(request.getMethod())
-            .version(HttpVersion.fromString(request.getProtocol()))
             .attribute(CLIENT_REQUEST_ATTRIBUTE, request);
     }