Source code

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.activemq.network;
018
019import java.io.IOException;
020import java.net.URI;
021import java.net.URISyntaxException;
022import java.util.Iterator;
023import java.util.Map;
024import java.util.concurrent.ConcurrentHashMap;
025import java.util.concurrent.ConcurrentMap;
026
027import javax.management.ObjectName;
028
029import org.apache.activemq.broker.BrokerService;
030import org.apache.activemq.broker.SslContext;
031import org.apache.activemq.command.DiscoveryEvent;
032import org.apache.activemq.transport.Transport;
033import org.apache.activemq.transport.TransportFactory;
034import org.apache.activemq.transport.discovery.DiscoveryAgent;
035import org.apache.activemq.transport.discovery.DiscoveryAgentFactory;
036import org.apache.activemq.transport.discovery.DiscoveryListener;
037import org.apache.activemq.util.IntrospectionSupport;
038import org.apache.activemq.util.ServiceStopper;
039import org.apache.activemq.util.ServiceSupport;
040import org.apache.activemq.util.URISupport;
041import org.slf4j.Logger;
042import org.slf4j.LoggerFactory;
043
044/**
045 * A network connector which uses a discovery agent to detect the remote brokers
046 * available and setup a connection to each available remote broker
047 *
048 * @org.apache.xbean.XBean element="networkConnector"
049 *
050 */
051public class DiscoveryNetworkConnector extends NetworkConnector implements DiscoveryListener {
052    private static final Logger LOG = LoggerFactory.getLogger(DiscoveryNetworkConnector.class);
053
054    private DiscoveryAgent discoveryAgent;
055    private Map<String, String> parameters;
056    private final ConcurrentMap<URI, DiscoveryEvent> activeEvents = new ConcurrentHashMap<URI, DiscoveryEvent>();
057    private URI discoveryUri;
058    public DiscoveryNetworkConnector() {
059    }
060
061    public DiscoveryNetworkConnector(URI discoveryURI) throws IOException {
062        setUri(discoveryURI);
063    }
064
065    public void setUri(URI discoveryURI) throws IOException {
066        this.discoveryUri = discoveryURI;
067        setDiscoveryAgent(DiscoveryAgentFactory.createDiscoveryAgent(discoveryURI));
068        try {
069            parameters = URISupport.parseParameters(discoveryURI);
070            // allow discovery agent to grab it's parameters
071            IntrospectionSupport.setProperties(getDiscoveryAgent(), parameters);
072        } catch (URISyntaxException e) {
073            LOG.warn("failed to parse query parameters from discoveryURI: {}", discoveryURI, e);
074        }
075    }
076
077    public URI getUri() {
078        return discoveryUri;
079    }
080
081    @Override
082    public void onServiceAdd(DiscoveryEvent event) {
083        // Ignore events once we start stopping.
084        if (serviceSupport.isStopped() || serviceSupport.isStopping()) {
085            return;
086        }
087        String url = event.getServiceName();
088        if (url != null) {
089            URI uri;
090            try {
091                uri = new URI(url);
092            } catch (URISyntaxException e) {
093                LOG.warn("Could not connect to remote URI: {} due to bad URI syntax: ", url, e);
094                return;
095            }
096
097            if (localURI.equals(uri)) {
098                LOG.debug("not connecting loopback: {}", uri);
099                return;
100            }
101
102            if (connectionFilter != null && !connectionFilter.connectTo(uri)) {
103                LOG.debug("connectionFilter disallows connection to: {}", uri);
104                return;
105            }
106
107            // Should we try to connect to that URI?
108            if (activeEvents.putIfAbsent(uri, event) != null) {
109                LOG.debug("Discovery agent generated a duplicate onServiceAdd event for: {}", uri);
110                return;
111            }
112
113            URI connectUri = uri;
114            try {
115                connectUri = URISupport.applyParameters(connectUri, parameters, DISCOVERED_OPTION_PREFIX);
116            } catch (URISyntaxException e) {
117                LOG.warn("could not apply query parameters: {} to: {}",parameters, connectUri, e);
118            }
119
120            LOG.info("Establishing network connection from {} to {}", localURI, connectUri);
121
122            Transport remoteTransport;
123            Transport localTransport;
124            try {
125                // Allows the transport to access the broker's ssl configuration.
126                if (getSslContext() != null) {
127                    SslContext.setCurrentSslContext(getSslContext());
128                } else {
129                    SslContext.setCurrentSslContext(getBrokerService().getSslContext());
130                }
131                try {
132                    remoteTransport = TransportFactory.connect(connectUri);
133                } catch (Exception e) {
134                    LOG.warn("Could not connect to remote URI: {}: {}", connectUri, e.getMessage());
135                    LOG.debug("Connection failure exception: ", e);
136                    try {
137                        discoveryAgent.serviceFailed(event);
138                    } catch (IOException e1) {
139                        LOG.debug("Failure while handling create remote transport failure event: {}", e1.getMessage(), e1);
140                    }
141                    return;
142                }
143                try {
144                    localTransport = createLocalTransport();
145                } catch (Exception e) {
146                    ServiceSupport.dispose(remoteTransport);
147                    LOG.warn("Could not connect to local URI: {}: {}", localURI, e.getMessage());
148                    LOG.debug("Connection failure exception: ", e);
149
150                    try {
151                        discoveryAgent.serviceFailed(event);
152                    } catch (IOException e1) {
153                        LOG.debug("Failure while handling create local transport failure event: {}", e1.getMessage(), e1);
154                    }
155                    return;
156                }
157            } finally {
158                SslContext.setCurrentSslContext(null);
159            }
160            NetworkBridge bridge = createBridge(localTransport, remoteTransport, event);
161            try {
162                synchronized (bridges) {
163                    bridges.put(uri, bridge);
164                }
165                bridge.start();
166            } catch (Exception e) {
167                ServiceSupport.dispose(localTransport);
168                ServiceSupport.dispose(remoteTransport);
169                LOG.warn("Could not start network bridge between: {} and: {} due to: {}", localURI, uri, e.getMessage());
170                LOG.debug("Start failure exception: ", e);
171                try {
172                    // Will remove bridge and active event.
173                    discoveryAgent.serviceFailed(event);
174                } catch (IOException e1) {
175                    LOG.debug("Discovery agent failure while handling failure event: {}", e1.getMessage(), e1);
176                }
177            }
178        }
179    }
180
181    @Override
182    public void onServiceRemove(DiscoveryEvent event) {
183        String url = event.getServiceName();
184        if (url != null) {
185            URI uri;
186            try {
187                uri = new URI(url);
188            } catch (URISyntaxException e) {
189                LOG.warn("Could not connect to remote URI: {} due to bad URI syntax: ", url, e);
190                return;
191            }
192
193            // Only remove bridge if this is the active discovery event for the URL.
194            if (activeEvents.remove(uri, event)) {
195                synchronized (bridges) {
196                    bridges.remove(uri);
197                }
198            }
199        }
200    }
201
202    public DiscoveryAgent getDiscoveryAgent() {
203        return discoveryAgent;
204    }
205
206    public void setDiscoveryAgent(DiscoveryAgent discoveryAgent) {
207        this.discoveryAgent = discoveryAgent;
208        if (discoveryAgent != null) {
209            this.discoveryAgent.setDiscoveryListener(this);
210        }
211    }
212
213    @Override
214    protected void handleStart() throws Exception {
215        if (discoveryAgent == null) {
216            throw new IllegalStateException("You must configure the 'discoveryAgent' property");
217        }
218        this.discoveryAgent.start();
219        super.handleStart();
220    }
221
222    @Override
223    protected void handleStop(ServiceStopper stopper) throws Exception {
224        for (Iterator<NetworkBridge> i = bridges.values().iterator(); i.hasNext();) {
225            NetworkBridge bridge = i.next();
226            try {
227                bridge.stop();
228            } catch (Exception e) {
229                stopper.onException(this, e);
230            }
231        }
232        bridges.clear();
233        activeEvents.clear();
234        try {
235            this.discoveryAgent.stop();
236        } catch (Exception e) {
237            stopper.onException(this, e);
238        }
239
240        super.handleStop(stopper);
241    }
242
243    protected NetworkBridge createBridge(Transport localTransport, Transport remoteTransport, final DiscoveryEvent event) {
244        class DiscoverNetworkBridgeListener extends MBeanNetworkListener {
245
246            public DiscoverNetworkBridgeListener(BrokerService brokerService, ObjectName connectorName) {
247                super(brokerService, DiscoveryNetworkConnector.this, connectorName);
248            }
249
250            @Override
251            public void bridgeFailed() {
252                if (!serviceSupport.isStopped()) {
253                    try {
254                        discoveryAgent.serviceFailed(event);
255                    } catch (IOException e) {
256                    }
257                }
258
259            }
260        }
261        NetworkBridgeListener listener = new DiscoverNetworkBridgeListener(getBrokerService(), getObjectName());
262
263        DemandForwardingBridge result = getBridgeFactory().createNetworkBridge(this, localTransport, remoteTransport, listener);
264        result.setBrokerService(getBrokerService());
265        return configureBridge(result);
266    }
267
268    @Override
269    public String toString() {
270        return "DiscoveryNetworkConnector:" + getName() + ":" + getBrokerService();
271    }
272}