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.ExtendedExchange;
026import org.apache.camel.Producer;
027import org.apache.camel.spi.CamelEvent;
028import org.apache.camel.support.EventNotifierSupport;
029import org.apache.camel.support.service.ServiceHelper;
030import org.apache.camel.util.ObjectHelper;
031import org.apache.camel.util.URISupport;
032import org.slf4j.Logger;
033import org.slf4j.LoggerFactory;
034
035/**
036 * A {@link org.apache.camel.spi.EventNotifier} which publishes the {@link EventObject} to some
037 * {@link org.apache.camel.Endpoint}.
038 * <p/>
039 * This notifier is only enabled when {@link CamelContext} is started. This avoids problems when sending notifications
040 * during start/shutdown of {@link CamelContext} which causes problems by sending those events to Camel routes by this
041 * notifier.
042 */
043public class PublishEventNotifier extends EventNotifierSupport implements CamelContextAware {
044
045    private static final Logger LOG = LoggerFactory.getLogger(PublishEventNotifier.class);
046
047    private Endpoint endpoint;
048    private String endpointUri;
049    private Producer producer;
050
051    @Override
052    public void notify(CamelEvent event) throws Exception {
053        // only notify when we are started
054        if (!isStarted()) {
055            LOG.debug("Cannot publish event as notifier is not started: {}", event);
056            return;
057        }
058
059        // only notify when camel context is running
060        if (!getCamelContext().getStatus().isStarted()) {
061            LOG.debug("Cannot publish event as CamelContext is not started: {}", event);
062            return;
063        }
064
065        Exchange exchange = producer.getEndpoint().createExchange();
066        exchange.getIn().setBody(event);
067
068        // make sure we don't send out events for this as well
069        // mark exchange as being published to event, to prevent creating new events
070        // for this as well (causing a endless flood of events)
071        exchange.adapt(ExtendedExchange.class).setNotifyEvent(true);
072        try {
073            producer.process(exchange);
074        } finally {
075            // and remove it when its done
076            exchange.adapt(ExtendedExchange.class).setNotifyEvent(false);
077        }
078    }
079
080    @Override
081    public boolean isEnabled(CamelEvent event) {
082        return true;
083    }
084
085    public Endpoint getEndpoint() {
086        return endpoint;
087    }
088
089    public void setEndpoint(Endpoint endpoint) {
090        this.endpoint = endpoint;
091    }
092
093    public String getEndpointUri() {
094        return endpointUri;
095    }
096
097    public void setEndpointUri(String endpointUri) {
098        this.endpointUri = endpointUri;
099    }
100
101    @Override
102    protected void doStart() throws Exception {
103        ObjectHelper.notNull(getCamelContext(), "camelContext", this);
104        if (endpoint == null && endpointUri == null) {
105            throw new IllegalArgumentException("Either endpoint or endpointUri must be configured");
106        }
107
108        if (endpoint == null) {
109            endpoint = getCamelContext().getEndpoint(endpointUri);
110        }
111
112        producer = endpoint.createProducer();
113        ServiceHelper.startService(producer);
114    }
115
116    @Override
117    protected void doStop() throws Exception {
118        ServiceHelper.stopService(producer);
119    }
120
121    @Override
122    public String toString() {
123        return "PublishEventNotifier[" + (endpoint != null ? endpoint : URISupport.sanitizeUri(endpointUri)) + "]";
124    }
125
126}