https://issues.apache.org/jira/browse/AMQ-5426
Fixing a race condition in ActiveMQMessageConsumer that could cause a NPE when the consumer is closing by only modifing pendingAck inside of the deliveredMessagesMutex Thanks to Michael Wong for providing the test case for this issue. (cherry picked from commit c02bc648460059b6dbc201fa21b7ee0ce2445082) Project: http://git-wip-us.apache.org/repos/asf/activemq/repo Commit: http://git-wip-us.apache.org/repos/asf/activemq/commit/8812cb9b Tree: http://git-wip-us.apache.org/repos/asf/activemq/tree/8812cb9b Diff: http://git-wip-us.apache.org/repos/asf/activemq/diff/8812cb9b Branch: refs/heads/activemq-5.13.x Commit: 8812cb9b8e7c91647230e8479dc2aca8762d458a Parents: 72c3a6d Author: Christopher L. Shannon (cshannon) <[email protected]> Authored: Tue Jul 5 20:35:07 2016 +0000 Committer: Christopher L. Shannon (cshannon) <[email protected]> Committed: Tue Jul 5 20:38:59 2016 +0000 ---------------------------------------------------------------------- .../activemq/ActiveMQMessageConsumer.java | 58 ++--- .../org/apache/activemq/bugs/AMQ5426Test.java | 227 +++++++++++++++++++ 2 files changed, 257 insertions(+), 28 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/activemq/blob/8812cb9b/activemq-client/src/main/java/org/apache/activemq/ActiveMQMessageConsumer.java ---------------------------------------------------------------------- diff --git a/activemq-client/src/main/java/org/apache/activemq/ActiveMQMessageConsumer.java b/activemq-client/src/main/java/org/apache/activemq/ActiveMQMessageConsumer.java index 90ca7c2..cc0908b 100755 --- a/activemq-client/src/main/java/org/apache/activemq/ActiveMQMessageConsumer.java +++ b/activemq-client/src/main/java/org/apache/activemq/ActiveMQMessageConsumer.java @@ -780,8 +780,8 @@ public class ActiveMQMessageConsumer implements MessageAvailableConsumer, StatsC void deliverAcks() { MessageAck ack = null; if (deliveryingAcknowledgements.compareAndSet(false, true)) { - if (isAutoAcknowledgeEach()) { - synchronized(deliveredMessages) { + synchronized(deliveredMessages) { + if (isAutoAcknowledgeEach()) { ack = makeAckForAllDeliveredMessages(MessageAck.STANDARD_ACK_TYPE); if (ack != null) { deliveredMessages.clear(); @@ -790,10 +790,10 @@ public class ActiveMQMessageConsumer implements MessageAvailableConsumer, StatsC ack = pendingAck; pendingAck = null; } + } else if (pendingAck != null && pendingAck.isStandardAck()) { + ack = pendingAck; + pendingAck = null; } - } else if (pendingAck != null && pendingAck.isStandardAck()) { - ack = pendingAck; - pendingAck = null; } if (ack != null) { final MessageAck ackToSend = ack; @@ -1035,31 +1035,33 @@ public class ActiveMQMessageConsumer implements MessageAvailableConsumer, StatsC deliveredCounter++; - MessageAck oldPendingAck = pendingAck; - pendingAck = new MessageAck(md, ackType, deliveredCounter); - pendingAck.setTransactionId(session.getTransactionContext().getTransactionId()); - if( oldPendingAck==null ) { - pendingAck.setFirstMessageId(pendingAck.getLastMessageId()); - } else if ( oldPendingAck.getAckType() == pendingAck.getAckType() ) { - pendingAck.setFirstMessageId(oldPendingAck.getFirstMessageId()); - } else { - // old pending ack being superseded by ack of another type, if is is not a delivered - // ack and hence important, send it now so it is not lost. - if (!oldPendingAck.isDeliveredAck()) { - LOG.debug("Sending old pending ack {}, new pending: {}", oldPendingAck, pendingAck); - session.sendAck(oldPendingAck); + synchronized(deliveredMessages) { + MessageAck oldPendingAck = pendingAck; + pendingAck = new MessageAck(md, ackType, deliveredCounter); + pendingAck.setTransactionId(session.getTransactionContext().getTransactionId()); + if( oldPendingAck==null ) { + pendingAck.setFirstMessageId(pendingAck.getLastMessageId()); + } else if ( oldPendingAck.getAckType() == pendingAck.getAckType() ) { + pendingAck.setFirstMessageId(oldPendingAck.getFirstMessageId()); } else { - LOG.debug("dropping old pending ack {}, new pending: {}", oldPendingAck, pendingAck); + // old pending ack being superseded by ack of another type, if is is not a delivered + // ack and hence important, send it now so it is not lost. + if (!oldPendingAck.isDeliveredAck()) { + LOG.debug("Sending old pending ack {}, new pending: {}", oldPendingAck, pendingAck); + session.sendAck(oldPendingAck); + } else { + LOG.debug("dropping old pending ack {}, new pending: {}", oldPendingAck, pendingAck); + } + } + // AMQ-3956 evaluate both expired and normal msgs as + // otherwise consumer may get stalled + if ((0.5 * info.getPrefetchSize()) <= (deliveredCounter + ackCounter - additionalWindowSize)) { + LOG.debug("ackLater: sending: {}", pendingAck); + session.sendAck(pendingAck); + pendingAck=null; + deliveredCounter = 0; + additionalWindowSize = 0; } - } - // AMQ-3956 evaluate both expired and normal msgs as - // otherwise consumer may get stalled - if ((0.5 * info.getPrefetchSize()) <= (deliveredCounter + ackCounter - additionalWindowSize)) { - LOG.debug("ackLater: sending: {}", pendingAck); - session.sendAck(pendingAck); - pendingAck=null; - deliveredCounter = 0; - additionalWindowSize = 0; } } http://git-wip-us.apache.org/repos/asf/activemq/blob/8812cb9b/activemq-unit-tests/src/test/java/org/apache/activemq/bugs/AMQ5426Test.java ---------------------------------------------------------------------- diff --git a/activemq-unit-tests/src/test/java/org/apache/activemq/bugs/AMQ5426Test.java b/activemq-unit-tests/src/test/java/org/apache/activemq/bugs/AMQ5426Test.java new file mode 100644 index 0000000..da09aaf --- /dev/null +++ b/activemq-unit-tests/src/test/java/org/apache/activemq/bugs/AMQ5426Test.java @@ -0,0 +1,227 @@ +/** + * 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.bugs; + +import static org.junit.Assert.assertFalse; + +import java.io.InterruptedIOException; +import java.net.URI; +import java.util.Random; +import java.util.concurrent.atomic.AtomicBoolean; +import java.util.concurrent.atomic.AtomicInteger; + +import javax.jms.Connection; +import javax.jms.ConnectionFactory; +import javax.jms.DeliveryMode; +import javax.jms.JMSException; +import javax.jms.Message; +import javax.jms.MessageConsumer; +import javax.jms.MessageListener; +import javax.jms.MessageProducer; +import javax.jms.Session; +import javax.jms.TextMessage; +import javax.jms.Topic; + +import org.apache.activemq.ActiveMQConnectionFactory; +import org.apache.activemq.broker.BrokerFactory; +import org.apache.activemq.broker.BrokerService; +import org.apache.activemq.broker.region.policy.PolicyEntry; +import org.apache.activemq.broker.region.policy.PolicyMap; +import org.apache.log4j.Appender; +import org.apache.log4j.AppenderSkeleton; +import org.apache.log4j.Level; +import org.apache.log4j.spi.LoggingEvent; +import org.junit.After; +import org.junit.Before; +import org.junit.Test; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class AMQ5426Test { + + private static final Logger LOG = LoggerFactory + .getLogger(AMQ5426Test.class); + + private BrokerService brokerService; + private String connectionUri; + private AtomicBoolean hasFailureInProducer = new AtomicBoolean(false); + private Thread producerThread; + private AtomicBoolean hasErrorInLogger; + private Appender errorDetectorAppender; + + protected ConnectionFactory createConnectionFactory() throws Exception { + ActiveMQConnectionFactory conFactory = new ActiveMQConnectionFactory( + connectionUri); + conFactory.setWatchTopicAdvisories(false); + conFactory.setOptimizeAcknowledge(true); + return conFactory; + } + + @Before + public void setUp() throws Exception { + hasFailureInProducer = new AtomicBoolean(false); + hasErrorInLogger = new AtomicBoolean(false); + brokerService = BrokerFactory.createBroker(new URI( + "broker://()/localhost?persistent=false&useJmx=true")); + + PolicyEntry policy = new PolicyEntry(); + policy.setTopicPrefetch(100); + PolicyMap pMap = new PolicyMap(); + pMap.setDefaultEntry(policy); + brokerService.addConnector("tcp://0.0.0.0:0"); + brokerService.start(); + connectionUri = brokerService.getTransportConnectorByScheme("tcp") + .getPublishableConnectString(); + + // Register an error listener to LOG4J + // The NPE will not be detectable as of V5.10 from + // ActiveMQConnection.setClientInternalExceptionListener + // since ActiveMQMessageConsumer.dispatch will silently catch and + // discard any RuntimeException + errorDetectorAppender = new AppenderSkeleton() { + @Override + public void close() { + // Do nothing + } + + @Override + public boolean requiresLayout() { + return false; + } + + @Override + protected void append(LoggingEvent event) { + if (event.getLevel().isGreaterOrEqual(Level.ERROR)) + hasErrorInLogger.set(true); + } + }; + + org.apache.log4j.Logger.getRootLogger().addAppender(errorDetectorAppender); + producerThread = new Thread(new Runnable() { + @Override + public void run() { + try { + Connection connection = createConnectionFactory() + .createConnection(); + connection.start(); + Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE); + Topic destination = session.createTopic("test.AMQ5426"); + LOG.debug("Created topic: {}", destination); + MessageProducer producer = session.createProducer(destination); + producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT); + producer.setTimeToLive(1000); + LOG.debug("Created producer: {}", producer); + + int i = 1; + while (!Thread.interrupted()) { + try { + TextMessage msg = session.createTextMessage(" testMessage " + i); + producer.send(msg); + try { + // Sleep for some nano seconds + Thread.sleep(0, 100); + } catch (InterruptedException e) { + // Restore the interrupt + Thread.currentThread().interrupt(); + } + LOG.debug("message sent: {}", i); + i++; + } catch (JMSException e) { + // Sometimes, we will gt a JMSException with nested + // InterruptedIOException when we interrupt the thread + if (!(e.getCause() != null && e.getCause() instanceof InterruptedIOException)) { + throw e; + } + } + } + + producer.close(); + session.close(); + connection.close(); + } catch (Exception e) { + LOG.error(e.getMessage(), e); + hasFailureInProducer.set(true); + } + } + }); + + producerThread.start(); + } + + @Test(timeout = 2 * 60 * 1000) + public void testConsumerProperlyClosedWithoutError() throws Exception { + Random rn = new Random(); + + final int NUMBER_OF_RUNS = 1000; + + for (int run = 0; run < NUMBER_OF_RUNS; run++) { + final AtomicInteger numberOfMessagesReceived = new AtomicInteger(0); + LOG.info("Starting run {} of {}", run, NUMBER_OF_RUNS); + + // Starts a consumer + Connection connection = createConnectionFactory().createConnection(); + connection.start(); + + Session session = connection.createSession(false, Session.DUPS_OK_ACKNOWLEDGE); + Topic destination = session.createTopic("test.AMQ5426"); + + LOG.debug("Created topic: {}", destination); + MessageConsumer consumer = session.createConsumer(destination); + consumer.setMessageListener(new MessageListener() { + + @Override + public void onMessage(Message message) { + LOG.debug("Received message"); + numberOfMessagesReceived.getAndIncrement(); + } + }); + LOG.debug("Created consumer: {}", consumer); + + try { + // Sleep for a random time + Thread.sleep(rn.nextInt(5) + 1); + } catch (InterruptedException e) { + // Restore the interrupt + Thread.currentThread().interrupt(); + } + + // Close the consumer + LOG.debug("Closing consumer"); + consumer.close(); + session.close(); + connection.close(); + + assertFalse("Exception in Producer Thread", hasFailureInProducer.get()); + assertFalse("Error detected in Logger", hasErrorInLogger.get()); + LOG.info("Run {} of {} completed, message received: {}", run, + NUMBER_OF_RUNS, numberOfMessagesReceived.get()); + } + } + + @After + public void tearDown() throws Exception { + // Interrupt the producer thread + LOG.info("Shutdown producer thread"); + producerThread.interrupt(); + producerThread.join(); + brokerService.stop(); + brokerService.waitUntilStopped(); + + assertFalse("Exception in Producer Thread", hasFailureInProducer.get()); + assertFalse("Error detected in Logger", hasErrorInLogger.get()); + } +}
