Disable ShallowEtagHeaderFilter for HTTP streaming

Issue: SPR-12960

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