Close response on errors writing to the outputStream (#1372)

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/filters/post/SendResponseFilter.java

@@ -17,6 +17,7 @@
 package org.springframework.cloud.netflix.zuul.filters.post;
 
 import java.io.ByteArrayInputStream;
+import java.io.Closeable;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -184,30 +185,35 @@ public class SendResponseFilter extends ZuulFilter {
 			}
 		}
 		finally {
+			/**
+			* Closing the wrapping InputStream itself has no effect on closing the underlying tcp connection since it's a wrapped stream. I guess for http
+			* keep-alive. When closing the wrapping stream it tries to reach the end of the current request, which is impossible for infinite http streams. So
+			* instead of closing the InputStream we close the HTTP response.
+			*
+			* @author Johannes Edmeier
+			*/
 			try {
-				if (is != null) {
-					is.close();
+				Object zuulResponse = RequestContext.getCurrentContext()
+						.get("zuulResponse");
+				if (zuulResponse instanceof Closeable) {
+					((Closeable) zuulResponse).close();
 				}
 				outStream.flush();
 				// The container will close the stream for us
 			}
 			catch (IOException ex) {
+			log.warn("Error while sending response to client: " + ex.getMessage());
 			}
 		}
 	}
 
 	private void writeResponse(InputStream zin, OutputStream out) throws Exception {
-		try {
 		byte[] bytes = buffers.get();
 		int bytesRead = -1;
 		while ((bytesRead = zin.read(bytes)) != -1) {
 			out.write(bytes, 0, bytesRead);
 		}
 	}
-		catch(IOException ioe) {
-			log.warn("Error while sending response to client: "+ioe.getMessage());
-		}
-	}
 
 	private void addResponseHeaders() {
 		RequestContext context = RequestContext.getCurrentContext();

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/filters/route/RibbonRoutingFilter.java

@@ -218,6 +218,7 @@ public class RibbonRoutingFilter extends ZuulFilter {
 
 	protected void setResponse(ClientHttpResponse resp)
 			throws ClientException, IOException {
+		RequestContext.getCurrentContext().set("zuulResponse", resp);
 		this.helper.setResponse(resp.getStatusCode().value(),
 				resp.getBody() == null ? null : resp.getBody(), resp.getHeaders());
 	}

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/filters/route/SimpleHostRoutingFilter.java

@@ -42,10 +42,10 @@ import org.apache.http.HttpHost;
 import org.apache.http.HttpRequest;
 import org.apache.http.HttpResponse;
 import org.apache.http.ProtocolException;
-import org.apache.http.client.HttpClient;
 import org.apache.http.client.RedirectStrategy;
 import org.apache.http.client.config.CookieSpecs;
 import org.apache.http.client.config.RequestConfig;
+import org.apache.http.client.methods.CloseableHttpResponse;
 import org.apache.http.client.methods.HttpPatch;
 import org.apache.http.client.methods.HttpPost;
 import org.apache.http.client.methods.HttpPut;
@@ -192,8 +192,8 @@ public class SimpleHostRoutingFilter extends ZuulFilter {
 		this.helper.addIgnoredHeaders();
 
 		try {
-			HttpResponse response = forward(this.httpClient, verb, uri, request, headers,
-					params, requestEntity);
+			CloseableHttpResponse response = forward(this.httpClient, verb, uri, request,
+					headers, params, requestEntity);
 			setResponse(response);
 		}
 		catch (Exception ex) {
@@ -278,8 +278,8 @@ public class SimpleHostRoutingFilter extends ZuulFilter {
 				}).build();
 	}
 
-	private HttpResponse forward(HttpClient httpclient, String verb, String uri,
-			HttpServletRequest request, MultiValueMap<String, String> headers,
+	private CloseableHttpResponse forward(CloseableHttpClient httpclient, String verb,
+			String uri, HttpServletRequest request, MultiValueMap<String, String> headers,
 			MultiValueMap<String, String> params, InputStream requestEntity)
 			throws Exception {
 		Map<String, Object> info = this.helper.debug(verb, uri, headers, params,
@@ -301,7 +301,8 @@ public class SimpleHostRoutingFilter extends ZuulFilter {
 		try {
 			log.debug(httpHost.getHostName() + " " + httpHost.getPort() + " "
 					+ httpHost.getSchemeName());
-			HttpResponse zuulResponse = forwardRequest(httpclient, httpHost, httpRequest);
+			CloseableHttpResponse zuulResponse = forwardRequest(httpclient, httpHost,
+					httpRequest);
 			this.helper.appendDebug(info, zuulResponse.getStatusLine().getStatusCode(),
 					revertHeaders(zuulResponse.getAllHeaders()));
 			return zuulResponse;
@@ -379,8 +380,8 @@ public class SimpleHostRoutingFilter extends ZuulFilter {
 		return list.toArray(new BasicHeader[0]);
 	}
 
-	private HttpResponse forwardRequest(HttpClient httpclient, HttpHost httpHost,
-			HttpRequest httpRequest) throws IOException {
+	private CloseableHttpResponse forwardRequest(CloseableHttpClient httpclient,
+			HttpHost httpHost, HttpRequest httpRequest) throws IOException {
 		return httpclient.execute(httpHost, httpRequest);
 	}
 
@@ -407,6 +408,7 @@ public class SimpleHostRoutingFilter extends ZuulFilter {
 	}
 
 	private void setResponse(HttpResponse response) throws IOException {
+		RequestContext.getCurrentContext().set("zuulResponse", response);
 		this.helper.setResponse(response.getStatusLine().getStatusCode(),
 				response.getEntity() == null ? null : response.getEntity().getContent(),
 				revertHeaders(response.getAllHeaders()));

spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/zuul/filters/post/SendResponseFilterTests.java

@@ -16,9 +16,26 @@
 
 package org.springframework.cloud.netflix.zuul.filters.post;
 
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.anyInt;
+import static org.mockito.Matchers.isA;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.X_ZUUL_DEBUG_HEADER;
+import static org.hamcrest.Matchers.equalTo;
+
 import java.io.ByteArrayInputStream;
+import java.io.Closeable;
+import java.io.IOException;
+import java.lang.reflect.UndeclaredThrowableException;
 
+import javax.servlet.ServletOutputStream;
 import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 
 import org.junit.After;
 import org.junit.Before;
@@ -34,11 +51,6 @@ import com.netflix.zuul.constants.ZuulConstants;
 import com.netflix.zuul.context.Debug;
 import com.netflix.zuul.context.RequestContext;
 
-import static org.hamcrest.Matchers.equalTo;
-import static org.junit.Assert.assertThat;
-import static org.junit.Assert.assertTrue;
-import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.X_ZUUL_DEBUG_HEADER;
-
 /**
  * @author Spencer Gibb
  */
@@ -96,6 +108,34 @@ public class SendResponseFilterTests {
 		assertThat("wrong origin content length", contentLength, equalTo("6"));
 	}
 
+    @Test
+	public void closeResponseOutpusStreamError() throws Exception {
+        HttpServletResponse response = mock(HttpServletResponse.class);
+
+        RequestContext context = new RequestContext();
+        context.setRequest(new MockHttpServletRequest());
+        context.setResponse(response);
+        context.setResponseDataStream(new ByteArrayInputStream("Hello\n".getBytes("UTF-8")));
+        Closeable zuulResponse = mock(Closeable.class);
+        context.set("zuulResponse", zuulResponse);
+        RequestContext.testSetCurrentContext(context);
+
+        SendResponseFilter filter = new SendResponseFilter();
+
+        ServletOutputStream zuuloutputstream = mock(ServletOutputStream.class);
+        doThrow(new IOException("Response to client closed")).when(zuuloutputstream).write(isA(byte[].class), anyInt(), anyInt());
+
+        when(response.getOutputStream()).thenReturn(zuuloutputstream);
+
+        try {
+            filter.run();
+        } catch (UndeclaredThrowableException ex) {
+            assertThat(ex.getUndeclaredThrowable().getMessage(), is("Response to client closed"));
+        }
+
+        verify(zuulResponse).close();
+    }
+
 	private void runFilter(String characterEncoding, String content, boolean streamContent) throws Exception {
 		MockHttpServletResponse response = new MockHttpServletResponse();
 		SendResponseFilter filter = createFilter(content, characterEncoding, response, streamContent);