Fix for NPE when connection is reset by peer (#1771)

* Unit test that reproduces the NPE when connection is reset by peer

* Changed future.channel() to channel which is guarded to be non null

* Higher request timeout because the test seems to fail regularly on Github

Also the duration of running the build in Github varies

Co-authored-by: Rachid Ben Moussa <[email protected]>

Author: rachid-o

client/src/main/java/org/asynchttpclient/netty/request/NettyRequestSender.java

@@ -464,7 +464,7 @@ private void scheduleReadTimeout(NettyResponseFuture<?> nettyResponseFuture) {
   public void abort(Channel channel, NettyResponseFuture<?> future, Throwable t) {
 
     if (channel != null) {
-      Object attribute = Channels.getAttribute(future.channel());
+      Object attribute = Channels.getAttribute(channel);
       if (attribute instanceof StreamedResponsePublisher) {
         ((StreamedResponsePublisher) attribute).setError(t);
       }

client/src/test/java/org/asynchttpclient/netty/NettyConnectionResetByPeerTest.java

@@ -0,0 +1,108 @@
+package org.asynchttpclient.netty;
+
+import org.asynchttpclient.DefaultAsyncHttpClient;
+import org.asynchttpclient.DefaultAsyncHttpClientConfig;
+import org.asynchttpclient.RequestBuilder;
+import org.testng.annotations.BeforeTest;
+import org.testng.annotations.Test;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.net.SocketException;
+import java.util.Arrays;
+import java.util.concurrent.Exchanger;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeoutException;
+import java.util.function.Consumer;
+
+import static org.hamcrest.CoreMatchers.instanceOf;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.not;
+import static org.testng.Assert.assertTrue;
+
+public class NettyConnectionResetByPeerTest {
+
+    private String resettingServerAddress;
+
+    @BeforeTest
+    public void setUp() {
+        resettingServerAddress = createResettingServer();
+    }
+
+    @Test
+    public void testAsyncHttpClientConnectionResetByPeer() throws InterruptedException {
+        try {
+            DefaultAsyncHttpClientConfig config = new DefaultAsyncHttpClientConfig.Builder()
+                    .setRequestTimeout(1500)
+                    .build();
+            new DefaultAsyncHttpClient(config).executeRequest(
+                    new RequestBuilder("GET").setUrl(resettingServerAddress)
+            )
+                    .get();
+        } catch (ExecutionException e) {
+            Throwable ex = e.getCause();
+            assertThat(ex, is(instanceOf(IOException.class)));
+        }
+    }
+
+    private static String createResettingServer() {
+        return createServer(sock -> {
+            try (Socket socket = sock) {
+                socket.setSoLinger(true, 0);
+                InputStream inputStream = socket.getInputStream();
+                //to not eliminate read
+                OutputStream os = new OutputStream() {
+                    @Override
+                    public void write(int b) {
+                        // Do nothing
+                    }
+                };
+                os.write(startRead(inputStream));
+            } catch (IOException e) {
+                throw new RuntimeException(e);
+            }
+        });
+    }
+
+    private static String createServer(Consumer<Socket> handler) {
+        Exchanger<Integer> portHolder = new Exchanger<>();
+        Thread t = new Thread(() -> {
+            try (ServerSocket ss = new ServerSocket(0)) {
+                portHolder.exchange(ss.getLocalPort());
+                while (true) {
+                    handler.accept(ss.accept());
+                }
+            } catch (Exception e) {
+                if (e instanceof InterruptedException) {
+                    Thread.currentThread()
+                            .interrupt();
+                }
+                throw new RuntimeException(e);
+            }
+        });
+        t.setDaemon(true);
+        t.start();
+        return tryGetAddress(portHolder);
+    }
+
+    private static String tryGetAddress(Exchanger<Integer> portHolder) {
+        try {
+            return "http://localhost:" + portHolder.exchange(0);
+        } catch (InterruptedException e) {
+            Thread.currentThread()
+                    .interrupt();
+            throw new RuntimeException(e);
+        }
+    }
+
+    private static byte[] startRead(InputStream inputStream) throws IOException {
+        byte[] buffer = new byte[4];
+        int length = inputStream.read(buffer);
+        return Arrays.copyOf(buffer, length);
+    }
+
+}