Disable ShallowEtagHeaderFilter for HTTP streaming

Issue: SPR-12960

spring-web/src/main/java/org/springframework/web/filter/ShallowEtagHeaderFilter.java

@@ -18,8 +18,12 @@ package org.springframework.web.filter;
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.PrintWriter;
+
 import javax.servlet.FilterChain;
 import javax.servlet.ServletException;
+import javax.servlet.ServletOutputStream;
+import javax.servlet.ServletRequest;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
@@ -55,11 +59,12 @@ public class ShallowEtagHeaderFilter extends OncePerRequestFilter {
 
 	private static final String DIRECTIVE_NO_STORE = "no-store";
 
-
 	/** Checking for Servlet 3.0+ HttpServletResponse.getHeader(String) */
 	private static final boolean responseGetHeaderAvailable =
 			ClassUtils.hasMethod(HttpServletResponse.class, "getHeader", String.class);
 
+	private static final String STREAMING_ATTRIBUTE = ShallowEtagHeaderFilter.class.getName() + ".STREAMING";
+
 
 	/**
 	 * The default value is "false" so that the filter may delay the generation of
@@ -76,12 +81,12 @@ public class ShallowEtagHeaderFilter extends OncePerRequestFilter {
 
 		HttpServletResponse responseToUse = response;
 		if (!isAsyncDispatch(request) && !(response instanceof ContentCachingResponseWrapper)) {
-			responseToUse = new ContentCachingResponseWrapper(response);
+			responseToUse = new HttpStreamingAwareContentCachingResponseWrapper(response, request);
 		}
 
 		filterChain.doFilter(request, responseToUse);
 
-		if (!isAsyncStarted(request)) {
+		if (!isAsyncStarted(request) && !isContentCachingDisabled(request)) {
 			updateResponse(request, responseToUse);
 		}
 	}
@@ -90,7 +95,6 @@ public class ShallowEtagHeaderFilter extends OncePerRequestFilter {
 		ContentCachingResponseWrapper responseWrapper =
 				WebUtils.getNativeResponse(response, ContentCachingResponseWrapper.class);
 		Assert.notNull(responseWrapper, "ShallowEtagResponseWrapper not found");
-
 		HttpServletResponse rawResponse = (HttpServletResponse) responseWrapper.getResponse();
 		int statusCode = responseWrapper.getStatusCode();
 
@@ -169,4 +173,48 @@ public class ShallowEtagHeaderFilter extends OncePerRequestFilter {
 		return builder.toString();
 	}
 
+	/**
+	 * This method can be used to disable the content caching response wrapper
+	 * of the ShallowEtagHeaderFilter. This can be done before the start of HTTP
+	 * streaming for example where the response will be written to asynchronously
+	 * and not in the context of a Servlet container thread.
+	 * @since 4.2
+	 */
+	public static void disableContentCaching(ServletRequest request) {
+		Assert.notNull(request);
+		request.setAttribute(STREAMING_ATTRIBUTE, true);
+	}
+
+	private static boolean isContentCachingDisabled(HttpServletRequest request) {
+		return (request.getAttribute(STREAMING_ATTRIBUTE) != null);
+	}
+
+
+	private static class HttpStreamingAwareContentCachingResponseWrapper extends ContentCachingResponseWrapper {
+
+		private final HttpServletRequest request;
+
+
+		public HttpStreamingAwareContentCachingResponseWrapper(HttpServletResponse response,
+				HttpServletRequest request) {
+
+			super(response);
+			this.request = request;
+		}
+
+		@Override
+		public ServletOutputStream getOutputStream() throws IOException {
+			return (useRawResponse() ? getResponse().getOutputStream() : super.getOutputStream());
+		}
+
+		@Override
+		public PrintWriter getWriter() throws IOException {
+			return (useRawResponse() ? getResponse().getWriter() : super.getWriter());
+		}
+
+		private boolean useRawResponse() {
+			return isContentCachingDisabled(this.request);
+		}
+	}
+
 }

spring-web/src/main/java/org/springframework/web/util/ContentCachingResponseWrapper.java

@@ -91,7 +91,7 @@ public class ContentCachingResponseWrapper extends HttpServletResponseWrapper {
 	}
 
 	@Override
-	public ServletOutputStream getOutputStream() {
+	public ServletOutputStream getOutputStream() throws IOException {
 		return this.outputStream;
 	}
 

spring-web/src/test/java/org/springframework/web/filter/ShallowEtagHeaderFilterTests.java

@@ -69,14 +69,10 @@ public class ShallowEtagHeaderFilterTests {
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
 		final byte[] responseBody = "Hello World".getBytes("UTF-8");
-		FilterChain filterChain = new FilterChain() {
-			@Override
-			public void doFilter(ServletRequest filterRequest, ServletResponse filterResponse)
-					throws IOException, ServletException {
-				assertEquals("Invalid request passed", request, filterRequest);
-				((HttpServletResponse) filterResponse).setStatus(HttpServletResponse.SC_OK);
-				FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
-			}
+		FilterChain filterChain = (filterRequest, filterResponse) -> {
+			assertEquals("Invalid request passed", request, filterRequest);
+			((HttpServletResponse) filterResponse).setStatus(HttpServletResponse.SC_OK);
+			FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
 		};
 		filter.doFilter(request, response, filterChain);
 
@@ -93,15 +89,11 @@ public class ShallowEtagHeaderFilterTests {
 		request.addHeader("If-None-Match", etag);
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
-		FilterChain filterChain = new FilterChain() {
-			@Override
-			public void doFilter(ServletRequest filterRequest, ServletResponse filterResponse)
-					throws IOException, ServletException {
-				assertEquals("Invalid request passed", request, filterRequest);
-				byte[] responseBody = "Hello World".getBytes("UTF-8");
-				FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
-				filterResponse.setContentLength(responseBody.length);
-			}
+		FilterChain filterChain = (filterRequest, filterResponse) -> {
+			assertEquals("Invalid request passed", request, filterRequest);
+			byte[] responseBody = "Hello World".getBytes("UTF-8");
+			FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
+			filterResponse.setContentLength(responseBody.length);
 		};
 		filter.doFilter(request, response, filterChain);
 
@@ -118,15 +110,11 @@ public class ShallowEtagHeaderFilterTests {
 		request.addHeader("If-None-Match", etag);
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
-		FilterChain filterChain = new FilterChain() {
-			@Override
-			public void doFilter(ServletRequest filterRequest, ServletResponse filterResponse)
-					throws IOException, ServletException {
-				assertEquals("Invalid request passed", request, filterRequest);
-				((HttpServletResponse) filterResponse).setStatus(HttpServletResponse.SC_OK);
-				String responseBody = "Hello World";
-				FileCopyUtils.copy(responseBody, filterResponse.getWriter());
-			}
+		FilterChain filterChain = (filterRequest, filterResponse) -> {
+			assertEquals("Invalid request passed", request, filterRequest);
+			((HttpServletResponse) filterResponse).setStatus(HttpServletResponse.SC_OK);
+			String responseBody = "Hello World";
+			FileCopyUtils.copy(responseBody, filterResponse.getWriter());
 		};
 		filter.doFilter(request, response, filterChain);
 
@@ -136,20 +124,38 @@ public class ShallowEtagHeaderFilterTests {
 		assertArrayEquals("Invalid content", new byte[0], response.getContentAsByteArray());
 	}
 
+	// SPR-12960
+
+	@Test
+	public void filterWriterWithDisabledCaching() throws Exception {
+		final MockHttpServletRequest request = new MockHttpServletRequest("GET", "/hotels");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+
+		final byte[] responseBody = "Hello World".getBytes("UTF-8");
+		FilterChain filterChain = (filterRequest, filterResponse) -> {
+			assertEquals("Invalid request passed", request, filterRequest);
+			((HttpServletResponse) filterResponse).setStatus(HttpServletResponse.SC_OK);
+			FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
+		};
+
+		ShallowEtagHeaderFilter.disableContentCaching(request);
+		this.filter.doFilter(request, response, filterChain);
+
+		assertEquals(200, response.getStatus());
+		assertNull(response.getHeader("ETag"));
+		assertArrayEquals(responseBody, response.getContentAsByteArray());
+	}
+
 	@Test
 	public void filterSendError() throws Exception {
 		final MockHttpServletRequest request = new MockHttpServletRequest("GET", "/hotels");
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
 		final byte[] responseBody = "Hello World".getBytes("UTF-8");
-		FilterChain filterChain = new FilterChain() {
-			@Override
-			public void doFilter(ServletRequest filterRequest, ServletResponse filterResponse)
-					throws IOException, ServletException {
-				assertEquals("Invalid request passed", request, filterRequest);
-				FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
-				((HttpServletResponse) filterResponse).sendError(HttpServletResponse.SC_FORBIDDEN);
-			}
+		FilterChain filterChain = (filterRequest, filterResponse) -> {
+			assertEquals("Invalid request passed", request, filterRequest);
+			FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
+			((HttpServletResponse) filterResponse).sendError(HttpServletResponse.SC_FORBIDDEN);
 		};
 		filter.doFilter(request, response, filterChain);
 
@@ -165,14 +171,10 @@ public class ShallowEtagHeaderFilterTests {
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
 		final byte[] responseBody = "Hello World".getBytes("UTF-8");
-		FilterChain filterChain = new FilterChain() {
-			@Override
-			public void doFilter(ServletRequest filterRequest, ServletResponse filterResponse)
-					throws IOException, ServletException {
-				assertEquals("Invalid request passed", request, filterRequest);
-				FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
-				((HttpServletResponse) filterResponse).sendError(HttpServletResponse.SC_FORBIDDEN, "ERROR");
-			}
+		FilterChain filterChain = (filterRequest, filterResponse) -> {
+			assertEquals("Invalid request passed", request, filterRequest);
+			FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
+			((HttpServletResponse) filterResponse).sendError(HttpServletResponse.SC_FORBIDDEN, "ERROR");
 		};
 		filter.doFilter(request, response, filterChain);
 
@@ -189,14 +191,10 @@ public class ShallowEtagHeaderFilterTests {
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
 		final byte[] responseBody = "Hello World".getBytes("UTF-8");
-		FilterChain filterChain = new FilterChain() {
-			@Override
-			public void doFilter(ServletRequest filterRequest, ServletResponse filterResponse)
-					throws IOException, ServletException {
-				assertEquals("Invalid request passed", request, filterRequest);
-				FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
-				((HttpServletResponse) filterResponse).sendRedirect("http://www.google.com");
-			}
+		FilterChain filterChain = (filterRequest, filterResponse) -> {
+			assertEquals("Invalid request passed", request, filterRequest);
+			FileCopyUtils.copy(responseBody, filterResponse.getOutputStream());
+			((HttpServletResponse) filterResponse).sendRedirect("http://www.google.com");
 		};
 		filter.doFilter(request, response, filterChain);
 

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ResponseBodyEmitterReturnValueHandler.java

@@ -19,6 +19,8 @@ package org.springframework.web.servlet.mvc.method.annotation;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.util.List;
+
+import javax.servlet.ServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 import org.apache.commons.logging.Log;
@@ -37,6 +39,7 @@ import org.springframework.util.Assert;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.context.request.async.DeferredResult;
 import org.springframework.web.context.request.async.WebAsyncUtils;
+import org.springframework.web.filter.ShallowEtagHeaderFilter;
 import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
 import org.springframework.web.method.support.ModelAndViewContainer;
 
@@ -95,6 +98,9 @@ public class ResponseBodyEmitterReturnValueHandler implements HandlerMethodRetur
 			}
 		}
 
+		ServletRequest request = webRequest.getNativeRequest(ServletRequest.class);
+		ShallowEtagHeaderFilter.disableContentCaching(request);
+
 		Assert.isInstanceOf(ResponseBodyEmitter.class, returnValue);
 		ResponseBodyEmitter emitter = (ResponseBodyEmitter) returnValue;
 		emitter.extendResponse(outputMessage);

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/StreamingResponseBodyReturnValueHandler.java

@@ -18,11 +18,9 @@ package org.springframework.web.servlet.mvc.method.annotation;
 import java.io.OutputStream;
 import java.util.concurrent.Callable;
 
+import javax.servlet.ServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-
 import org.springframework.core.MethodParameter;
 import org.springframework.core.ResolvableType;
 import org.springframework.http.ResponseEntity;
@@ -31,6 +29,7 @@ import org.springframework.http.server.ServletServerHttpResponse;
 import org.springframework.util.Assert;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.context.request.async.WebAsyncUtils;
+import org.springframework.web.filter.ShallowEtagHeaderFilter;
 import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
 import org.springframework.web.method.support.ModelAndViewContainer;
 
@@ -45,9 +44,6 @@ import org.springframework.web.method.support.ModelAndViewContainer;
  */
 public class StreamingResponseBodyReturnValueHandler implements HandlerMethodReturnValueHandler {
 
-	private static final Log logger = LogFactory.getLog(StreamingResponseBodyReturnValueHandler.class);
-
-
 	@Override
 	public boolean supportsReturnType(MethodParameter returnType) {
 		if (StreamingResponseBody.class.isAssignableFrom(returnType.getParameterType())) {
@@ -84,6 +80,9 @@ public class StreamingResponseBodyReturnValueHandler implements HandlerMethodRet
 			}
 		}
 
+		ServletRequest request = webRequest.getNativeRequest(ServletRequest.class);
+		ShallowEtagHeaderFilter.disableContentCaching(request);
+
 		Assert.isInstanceOf(StreamingResponseBody.class, returnValue);
 		StreamingResponseBody streamingBody = (StreamingResponseBody) returnValue;
 

spring-websocket/src/main/java/org/springframework/web/socket/sockjs/transport/session/AbstractHttpSockJsSession.java

@@ -26,10 +26,14 @@ import java.util.Map;
 import java.util.Queue;
 import java.util.concurrent.LinkedBlockingQueue;
 
+import javax.servlet.ServletRequest;
+
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.server.ServerHttpAsyncRequestControl;
 import org.springframework.http.server.ServerHttpRequest;
 import org.springframework.http.server.ServerHttpResponse;
+import org.springframework.http.server.ServletServerHttpRequest;
+import org.springframework.web.filter.ShallowEtagHeaderFilter;
 import org.springframework.web.socket.CloseStatus;
 import org.springframework.web.socket.WebSocketExtension;
 import org.springframework.web.socket.WebSocketHandler;
@@ -202,6 +206,8 @@ public abstract class AbstractHttpSockJsSession extends AbstractSockJsSession {
 				this.asyncRequestControl = request.getAsyncRequestControl(response);
 				this.asyncRequestControl.start(-1);
 
+				disableShallowEtagHeaderFilter(request);
+
 				// Let "our" handler know before sending the open frame to the remote handler
 				delegateConnectionEstablished();
 
@@ -243,6 +249,8 @@ public abstract class AbstractHttpSockJsSession extends AbstractSockJsSession {
 				this.asyncRequestControl = request.getAsyncRequestControl(response);
 				this.asyncRequestControl.start(-1);
 
+				disableShallowEtagHeaderFilter(request);
+
 				handleRequestInternal(request, response, false);
 				this.readyToSend = isActive();
 			}
@@ -253,6 +261,13 @@ public abstract class AbstractHttpSockJsSession extends AbstractSockJsSession {
 		}
 	}
 
+	private void disableShallowEtagHeaderFilter(ServerHttpRequest request) {
+		if (request instanceof ServletServerHttpRequest) {
+			ServletRequest servletRequest = ((ServletServerHttpRequest) request).getServletRequest();
+			ShallowEtagHeaderFilter.disableContentCaching(servletRequest);
+		}
+	}
+
 	/**
 	 * Invoked when a SockJS transport request is received.
 	 * @param request the current request