001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.camel.component.cometd;
018    
019    import org.apache.camel.Exchange;
020    import org.apache.camel.Message;
021    import org.apache.camel.Processor;
022    import org.apache.camel.impl.DefaultConsumer;
023    import org.apache.camel.impl.DefaultMessage;
024    import org.apache.camel.util.ExchangeHelper;
025    import org.cometd.bayeux.server.ServerMessage;
026    import org.cometd.bayeux.server.ServerSession;
027    import org.cometd.server.AbstractService;
028    import org.cometd.server.BayeuxServerImpl;
029    
030    /**
031     * A Consumer for receiving messages using Cometd and Bayeux protocol.
032     */
033    public class CometdConsumer extends DefaultConsumer implements CometdProducerConsumer {
034    
035        private BayeuxServerImpl bayeux;
036        private final CometdEndpoint endpoint;
037        private ConsumerService service;
038    
039        public CometdConsumer(CometdEndpoint endpoint, Processor processor) {
040            super(endpoint, processor);
041            this.endpoint = endpoint;
042        }
043    
044        @Override
045        public void start() throws Exception {
046            super.start();
047            // must connect first
048            endpoint.connect(this);
049            service = new ConsumerService(endpoint.getPath(), bayeux, this);
050        }
051    
052        @Override
053        public void stop() throws Exception {
054            endpoint.disconnect(this);
055            super.stop();
056        }
057    
058        public void setBayeux(BayeuxServerImpl bayeux) {
059            this.bayeux = bayeux;
060        }
061    
062        public CometdEndpoint getEndpoint() {
063            return endpoint;
064        }
065        
066        public ConsumerService getConsumerService() {
067            return service;
068        }
069    
070        public static class ConsumerService extends AbstractService {
071    
072            private final CometdEndpoint endpoint;
073            private final CometdConsumer consumer;
074    
075            public ConsumerService(String channel, BayeuxServerImpl bayeux, CometdConsumer consumer) {
076                super(bayeux, channel);
077                this.consumer = consumer;
078                this.endpoint = consumer.getEndpoint();
079                addService(channel, "push");
080            }
081    
082            public void push(ServerSession remote, String channelName, ServerMessage cometdMessage, String messageId) throws Exception {
083                Object data = null;
084    
085                if (cometdMessage != null) {
086                    data = cometdMessage.getData();
087                }
088    
089                Message message = new DefaultMessage();
090                message.setBody(data);
091    
092                Exchange exchange = endpoint.createExchange();
093                exchange.setIn(message);
094    
095                consumer.getProcessor().process(exchange);
096    
097                if (ExchangeHelper.isOutCapable(exchange)) {
098                    Message camelOutMessage = exchange.getOut();
099                    remote.deliver(getServerSession(), channelName, camelOutMessage.getBody(), null);
100                }
101            }
102        }
103    
104    }