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 CamelContext camelContext;
048    private Endpoint endpoint;
049    private String endpointUri;
050    private Producer producer;
051
052    @Override
053    public void notify(CamelEvent event) throws Exception {
054        // only notify when we are started
055        if (!isStarted()) {
056            LOG.debug("Cannot publish event as notifier is not started: {}", event);
057            return;
058        }
059
060        // only notify when camel context is running
061        if (!camelContext.getStatus().isStarted()) {
062            LOG.debug("Cannot publish event as CamelContext is not started: {}", event);
063            return;
064        }
065
066        Exchange exchange = producer.getEndpoint().createExchange();
067        exchange.getIn().setBody(event);
068
069        // make sure we don't send out events for this as well
070        // mark exchange as being published to event, to prevent creating new events
071        // for this as well (causing a endless flood of events)
072        exchange.adapt(ExtendedExchange.class).setNotifyEvent(true);
073        try {
074            producer.process(exchange);
075        } finally {
076            // and remove it when its done
077            exchange.adapt(ExtendedExchange.class).setNotifyEvent(false);
078        }
079    }
080
081    @Override
082    public boolean isEnabled(CamelEvent event) {
083        return true;
084    }
085
086    @Override
087    public CamelContext getCamelContext() {
088        return camelContext;
089    }
090
091    @Override
092    public void setCamelContext(CamelContext camelContext) {
093        this.camelContext = camelContext;
094    }
095
096    public Endpoint getEndpoint() {
097        return endpoint;
098    }
099
100    public void setEndpoint(Endpoint endpoint) {
101        this.endpoint = endpoint;
102    }
103
104    public String getEndpointUri() {
105        return endpointUri;
106    }
107
108    public void setEndpointUri(String endpointUri) {
109        this.endpointUri = endpointUri;
110    }
111
112    @Override
113    protected void doStart() throws Exception {
114        ObjectHelper.notNull(camelContext, "camelContext", this);
115        if (endpoint == null && endpointUri == null) {
116            throw new IllegalArgumentException("Either endpoint or endpointUri must be configured");
117        }
118
119        if (endpoint == null) {
120            endpoint = camelContext.getEndpoint(endpointUri);
121        }
122
123        producer = endpoint.createProducer();
124        ServiceHelper.startService(producer);
125    }
126
127    @Override
128    protected void doStop() throws Exception {
129        ServiceHelper.stopService(producer);
130    }
131
132    @Override
133    public String toString() {
134        return "PublishEventNotifier[" + (endpoint != null ? endpoint : URISupport.sanitizeUri(endpointUri)) + "]";
135    }
136
137}