/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.activemq.transport.mqtt.strategy;
import static org.apache.activemq.transport.mqtt.MQTTProtocolSupport.convertActiveMQToMQTT;
import static org.apache.activemq.transport.mqtt.MQTTProtocolSupport.convertMQTTToActiveMQ;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.StringTokenizer;
import org.apache.activemq.ActiveMQPrefetchPolicy;
import org.apache.activemq.broker.region.QueueRegion;
import org.apache.activemq.broker.region.RegionBroker;
import org.apache.activemq.command.ActiveMQDestination;
import org.apache.activemq.command.ActiveMQQueue;
import org.apache.activemq.command.ActiveMQTopic;
import org.apache.activemq.command.ConsumerInfo;
import org.apache.activemq.command.DestinationInfo;
import org.apache.activemq.command.RemoveSubscriptionInfo;
import org.apache.activemq.command.Response;
import org.apache.activemq.command.SubscriptionInfo;
import org.apache.activemq.transport.mqtt.MQTTProtocolConverter;
import org.apache.activemq.transport.mqtt.MQTTProtocolException;
import org.apache.activemq.transport.mqtt.MQTTProtocolSupport;
import org.apache.activemq.transport.mqtt.MQTTSubscription;
import org.apache.activemq.transport.mqtt.ResponseHandler;
import org.fusesource.mqtt.client.QoS;
import org.fusesource.mqtt.codec.CONNECT;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Subscription strategy that converts all MQTT subscribes that would be durable to
* Virtual Topic Queue subscriptions. Also maps all publish requests to be prefixed
* with the VirtualTopic. prefix unless already present.
*/
public class MQTTVirtualTopicSubscriptionStrategy extends AbstractMQTTSubscriptionStrategy {
private static final String VIRTUALTOPIC_PREFIX = "VirtualTopic.";
private static final String VIRTUALTOPIC_CONSUMER_PREFIX = "Consumer.";
private static final Logger LOG = LoggerFactory.getLogger(MQTTVirtualTopicSubscriptionStrategy.class);
private final Set<ActiveMQQueue> restoredQueues = Collections.synchronizedSet(new HashSet<ActiveMQQueue>());
@Override
public void onConnect(CONNECT connect) throws MQTTProtocolException {
List<ActiveMQQueue> queues = lookupQueues(protocol.getClientId());
List<SubscriptionInfo> subs = lookupSubscription(protocol.getClientId());
// When clean session is true we must purge all of the client's old Queue subscriptions
// and any durable subscriptions created on the VirtualTopic instance as well.
if (connect.cleanSession()) {
deleteDurableQueues(queues);
deleteDurableSubs(subs);
} else {
restoreDurableQueue(queues);
restoreDurableSubs(subs);
}
}
@Override
public byte onSubscribe(String topicName, QoS requestedQoS) throws MQTTProtocolException {
ActiveMQDestination destination = null;
int prefetch = ActiveMQPrefetchPolicy.DEFAULT_QUEUE_PREFETCH;
ConsumerInfo consumerInfo = new ConsumerInfo(getNextConsumerId());
String converted = convertMQTTToActiveMQ(topicName);
if (!protocol.isCleanSession() && protocol.getClientId() != null && requestedQoS.ordinal() >= QoS.AT_LEAST_ONCE.ordinal()) {
if (converted.startsWith(VIRTUALTOPIC_PREFIX)) {
destination = new ActiveMQTopic(converted);
prefetch = ActiveMQPrefetchPolicy.DEFAULT_DURABLE_TOPIC_PREFETCH;
consumerInfo.setSubscriptionName(requestedQoS + ":" + topicName);
} else {
converted = VIRTUALTOPIC_CONSUMER_PREFIX +
convertMQTTToActiveMQ(protocol.getClientId()) + ":" + requestedQoS + "." +
VIRTUALTOPIC_PREFIX + converted;
destination = new ActiveMQQueue(converted);
prefetch = ActiveMQPrefetchPolicy.DEFAULT_QUEUE_PREFETCH;
}
} else {
if (!converted.startsWith(VIRTUALTOPIC_PREFIX)) {
converted = VIRTUALTOPIC_PREFIX + converted;
}
destination = new ActiveMQTopic(converted);
prefetch = ActiveMQPrefetchPolicy.DEFAULT_TOPIC_PREFETCH;
}
consumerInfo.setDestination(destination);
if (protocol.getActiveMQSubscriptionPrefetch() > 0) {
consumerInfo.setPrefetchSize(protocol.getActiveMQSubscriptionPrefetch());
} else {
consumerInfo.setPrefetchSize(prefetch);
}
consumerInfo.setRetroactive(true);
consumerInfo.setDispatchAsync(true);
return doSubscribe(consumerInfo, topicName, requestedQoS);
}
@Override
public void onReSubscribe(MQTTSubscription mqttSubscription) throws MQTTProtocolException {
ActiveMQDestination destination = mqttSubscription.getDestination();
// check whether the Queue has been recovered in restoreDurableQueue
// mark subscription available for recovery for duplicate subscription
if (destination.isQueue() && restoredQueues.remove(destination)) {
return;
}
// check whether the Topic has been recovered in restoreDurableSubs
// mark subscription available for recovery for duplicate subscription
if (destination.isTopic() && restoredDurableSubs.remove(destination.getPhysicalName())) {
return;
}
if (mqttSubscription.getDestination().isTopic()) {
super.onReSubscribe(mqttSubscription);
} else {
doUnSubscribe(mqttSubscription);
ConsumerInfo consumerInfo = mqttSubscription.getConsumerInfo();
consumerInfo.setConsumerId(getNextConsumerId());
doSubscribe(consumerInfo, mqttSubscription.getTopicName(), mqttSubscription.getQoS());
}
}
@Override
public void onUnSubscribe(String topicName) throws MQTTProtocolException {
MQTTSubscription subscription = mqttSubscriptionByTopic.remove(topicName);
if (subscription != null) {
doUnSubscribe(subscription);
if (subscription.getDestination().isQueue()) {
DestinationInfo remove = new DestinationInfo();
remove.setConnectionId(protocol.getConnectionId());
remove.setDestination(subscription.getDestination());
remove.setOperationType(DestinationInfo.REMOVE_OPERATION_TYPE);
protocol.sendToActiveMQ(remove, new ResponseHandler() {
@Override
public void onResponse(MQTTProtocolConverter converter, Response response) throws IOException {
// ignore failures..
}
});
} else if (subscription.getConsumerInfo().getSubscriptionName() != null) {
// also remove it from restored durable subscriptions set
restoredDurableSubs.remove(MQTTProtocolSupport.convertMQTTToActiveMQ(subscription.getTopicName()));
RemoveSubscriptionInfo rsi = new RemoveSubscriptionInfo();
rsi.setConnectionId(protocol.getConnectionId());
rsi.setSubscriptionName(subscription.getConsumerInfo().getSubscriptionName());
rsi.setClientId(protocol.getClientId());
protocol.sendToActiveMQ(rsi, new ResponseHandler() {
@Override
public void onResponse(MQTTProtocolConverter converter, Response response) throws IOException {
// ignore failures..
}
});
}
}
}
@Override
public ActiveMQDestination onSend(String topicName) {
ActiveMQTopic topic = new ActiveMQTopic(topicName);
if (topic.isComposite()) {
ActiveMQDestination[] composites = topic.getCompositeDestinations();
for (ActiveMQDestination composite : composites) {
composite.setPhysicalName(prefix(composite.getPhysicalName()));
}
ActiveMQTopic result = new ActiveMQTopic();
result.setCompositeDestinations(composites);
return result;
} else {
return new ActiveMQTopic(prefix(topicName));
}
}
private String prefix(String topicName) {
if (!topicName.startsWith(VIRTUALTOPIC_PREFIX)) {
return VIRTUALTOPIC_PREFIX + topicName;
} else {
return topicName;
}
}
@Override
public String onSend(ActiveMQDestination destination) {
String destinationName = destination.getPhysicalName();
int position = destinationName.indexOf(VIRTUALTOPIC_PREFIX);
if (position >= 0) {
destinationName = destinationName.substring(position + VIRTUALTOPIC_PREFIX.length()).substring(0);
}
return destinationName;
}
@Override
public boolean isControlTopic(ActiveMQDestination destination) {
String destinationName = destination.getPhysicalName();
if (destinationName.startsWith("$") || destinationName.startsWith(VIRTUALTOPIC_PREFIX + "$")) {
return true;
}
return false;
}
private void deleteDurableQueues(List<ActiveMQQueue> queues) {
try {
for (ActiveMQQueue queue : queues) {
LOG.debug("Removing queue subscription for {} ",queue.getPhysicalName());
DestinationInfo removeAction = new DestinationInfo();
removeAction.setConnectionId(protocol.getConnectionId());
removeAction.setDestination(queue);
removeAction.setOperationType(DestinationInfo.REMOVE_OPERATION_TYPE);
protocol.sendToActiveMQ(removeAction, new ResponseHandler() {
@Override
public void onResponse(MQTTProtocolConverter converter, Response response) throws IOException {
// ignore failures..
}
});
}
} catch (Throwable e) {
LOG.warn("Could not delete the MQTT queue subscriptions.", e);
}
}
private void restoreDurableQueue(List<ActiveMQQueue> queues) {
try {
for (ActiveMQQueue queue : queues) {
String name = queue.getPhysicalName().substring(VIRTUALTOPIC_CONSUMER_PREFIX.length());
StringTokenizer tokenizer = new StringTokenizer(name);
tokenizer.nextToken(":.");
String qosString = tokenizer.nextToken();
tokenizer.nextToken();
String topicName = convertActiveMQToMQTT(tokenizer.nextToken("").substring(1));
QoS qoS = QoS.valueOf(qosString);
LOG.trace("Restoring queue subscription: {}:{}", topicName, qoS);
ConsumerInfo consumerInfo = new ConsumerInfo(getNextConsumerId());
consumerInfo.setDestination(queue);
consumerInfo.setPrefetchSize(ActiveMQPrefetchPolicy.DEFAULT_QUEUE_PREFETCH);
if (protocol.getActiveMQSubscriptionPrefetch() > 0) {
consumerInfo.setPrefetchSize(protocol.getActiveMQSubscriptionPrefetch());
}
consumerInfo.setRetroactive(true);
consumerInfo.setDispatchAsync(true);
doSubscribe(consumerInfo, topicName, qoS);
// mark this durable subscription as restored by Broker
restoredQueues.add(queue);
}
} catch (IOException e) {
LOG.warn("Could not restore the MQTT queue subscriptions.", e);
}
}
List<ActiveMQQueue> lookupQueues(String clientId) throws MQTTProtocolException {
List<ActiveMQQueue> result = new ArrayList<ActiveMQQueue>();
RegionBroker regionBroker;
try {
regionBroker = (RegionBroker) brokerService.getBroker().getAdaptor(RegionBroker.class);
} catch (Exception e) {
throw new MQTTProtocolException("Error recovering queues: " + e.getMessage(), false, e);
}
final QueueRegion queueRegion = (QueueRegion) regionBroker.getQueueRegion();
for (ActiveMQDestination destination : queueRegion.getDestinationMap().keySet()) {
if (destination.isQueue() && !destination.isTemporary()) {
if (destination.getPhysicalName().startsWith("Consumer." + clientId + ":")) {
LOG.debug("Recovered client sub: {} on connect", destination.getPhysicalName());
result.add((ActiveMQQueue) destination);
}
}
}
return result;
}
}