001/*
002 * Copyright 2002-2017 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.web.socket.messaging;
018
019import org.springframework.messaging.Message;
020import org.springframework.messaging.simp.stomp.StompCommand;
021import org.springframework.messaging.simp.stomp.StompHeaderAccessor;
022import org.springframework.messaging.support.MessageBuilder;
023import org.springframework.messaging.support.MessageHeaderAccessor;
024import org.springframework.util.Assert;
025
026/**
027 * A {@link SubProtocolErrorHandler} for use with STOMP.
028 *
029 * @author Rossen Stoyanchev
030 * @since 4.2
031 */
032public class StompSubProtocolErrorHandler implements SubProtocolErrorHandler<byte[]> {
033
034        private static final byte[] EMPTY_PAYLOAD = new byte[0];
035
036
037        @Override
038        public Message<byte[]> handleClientMessageProcessingError(Message<byte[]> clientMessage, Throwable ex) {
039                StompHeaderAccessor accessor = StompHeaderAccessor.create(StompCommand.ERROR);
040                accessor.setMessage(ex.getMessage());
041                accessor.setLeaveMutable(true);
042
043                StompHeaderAccessor clientHeaderAccessor = null;
044                if (clientMessage != null) {
045                        clientHeaderAccessor = MessageHeaderAccessor.getAccessor(clientMessage, StompHeaderAccessor.class);
046                        String receiptId = clientHeaderAccessor.getReceipt();
047                        if (receiptId != null) {
048                                accessor.setReceiptId(receiptId);
049                        }
050                }
051
052                return handleInternal(accessor, EMPTY_PAYLOAD, ex, clientHeaderAccessor);
053        }
054
055        @Override
056        public Message<byte[]> handleErrorMessageToClient(Message<byte[]> errorMessage) {
057                StompHeaderAccessor accessor = MessageHeaderAccessor.getAccessor(errorMessage, StompHeaderAccessor.class);
058                Assert.notNull(accessor, "Expected STOMP headers");
059                if (!accessor.isMutable()) {
060                        accessor = StompHeaderAccessor.wrap(errorMessage);
061                }
062                return handleInternal(accessor, errorMessage.getPayload(), null, null);
063        }
064
065        protected Message<byte[]> handleInternal(StompHeaderAccessor errorHeaderAccessor,
066                        byte[] errorPayload, Throwable cause, StompHeaderAccessor clientHeaderAccessor) {
067
068                return MessageBuilder.createMessage(errorPayload, errorHeaderAccessor.getMessageHeaders());
069        }
070
071}