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 */
017package org.apache.camel.management;
018
019import java.util.EventObject;
020
021import org.apache.camel.CamelContext;
022import org.apache.camel.CamelContextAware;
023import org.apache.camel.Endpoint;
024import org.apache.camel.Exchange;
025import org.apache.camel.Producer;
026import org.apache.camel.spi.CamelEvent;
027import org.apache.camel.support.EventNotifierSupport;
028import org.apache.camel.support.service.ServiceHelper;
029import org.apache.camel.util.ObjectHelper;
030import org.apache.camel.util.URISupport;
031import org.slf4j.Logger;
032import org.slf4j.LoggerFactory;
033
034/**
035 * A {@link org.apache.camel.spi.EventNotifier} which publishes the {@link EventObject} to some
036 * {@link org.apache.camel.Endpoint}.
037 * <p/>
038 * This notifier is only enabled when {@link CamelContext} is started. This avoids problems when sending notifications
039 * during start/shutdown of {@link CamelContext} which causes problems by sending those events to Camel routes by this
040 * notifier.
041 */
042public class PublishEventNotifier extends EventNotifierSupport implements CamelContextAware {
043
044    private static final Logger LOG = LoggerFactory.getLogger(PublishEventNotifier.class);
045
046    private Endpoint endpoint;
047    private String endpointUri;
048    private Producer producer;
049
050    @Override
051    public void notify(CamelEvent event) throws Exception {
052        // only notify when we are started
053        if (!isStarted()) {
054            LOG.debug("Cannot publish event as notifier is not started: {}", event);
055            return;
056        }
057
058        // only notify when camel context is running
059        if (!getCamelContext().getStatus().isStarted()) {
060            LOG.debug("Cannot publish event as CamelContext is not started: {}", event);
061            return;
062        }
063
064        Exchange exchange = producer.getEndpoint().createExchange();
065        exchange.getIn().setBody(event);
066
067        // make sure we don't send out events for this as well
068        // mark exchange as being published to event, to prevent creating new events
069        // for this as well (causing a endless flood of events)
070        exchange.getExchangeExtension().setNotifyEvent(true);
071        try {
072            producer.process(exchange);
073        } finally {
074            // and remove it when its done
075            exchange.getExchangeExtension().setNotifyEvent(false);
076        }
077    }
078
079    @Override
080    public boolean isEnabled(CamelEvent event) {
081        return true;
082    }
083
084    public Endpoint getEndpoint() {
085        return endpoint;
086    }
087
088    public void setEndpoint(Endpoint endpoint) {
089        this.endpoint = endpoint;
090    }
091
092    public String getEndpointUri() {
093        return endpointUri;
094    }
095
096    public void setEndpointUri(String endpointUri) {
097        this.endpointUri = endpointUri;
098    }
099
100    @Override
101    protected void doStart() throws Exception {
102        ObjectHelper.notNull(getCamelContext(), "camelContext", this);
103        if (endpoint == null && endpointUri == null) {
104            throw new IllegalArgumentException("Either endpoint or endpointUri must be configured");
105        }
106
107        if (endpoint == null) {
108            endpoint = getCamelContext().getEndpoint(endpointUri);
109        }
110
111        producer = endpoint.createProducer();
112        ServiceHelper.startService(producer);
113    }
114
115    @Override
116    protected void doStop() throws Exception {
117        ServiceHelper.stopService(producer);
118    }
119
120    @Override
121    public String toString() {
122        return "PublishEventNotifier[" + (endpoint != null ? endpoint : URISupport.sanitizeUri(endpointUri)) + "]";
123    }
124
125}