/**
* 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.amqp.protocol;
import static org.apache.activemq.transport.amqp.AmqpSupport.toBytes;
import static org.apache.activemq.transport.amqp.AmqpSupport.toLong;
import java.io.IOException;
import java.util.HashSet;
import java.util.Set;
import org.apache.activemq.command.ActiveMQDestination;
import org.apache.activemq.command.ConnectionId;
import org.apache.activemq.command.ExceptionResponse;
import org.apache.activemq.command.LocalTransactionId;
import org.apache.activemq.command.Response;
import org.apache.activemq.command.TransactionInfo;
import org.apache.activemq.transport.amqp.AmqpProtocolConverter;
import org.apache.activemq.transport.amqp.ResponseHandler;
import org.apache.qpid.proton.Proton;
import org.apache.qpid.proton.amqp.Binary;
import org.apache.qpid.proton.amqp.Symbol;
import org.apache.qpid.proton.amqp.messaging.Accepted;
import org.apache.qpid.proton.amqp.messaging.AmqpValue;
import org.apache.qpid.proton.amqp.messaging.Rejected;
import org.apache.qpid.proton.amqp.transaction.Declare;
import org.apache.qpid.proton.amqp.transaction.Declared;
import org.apache.qpid.proton.amqp.transaction.Discharge;
import org.apache.qpid.proton.amqp.transport.ErrorCondition;
import org.apache.qpid.proton.engine.Delivery;
import org.apache.qpid.proton.engine.Receiver;
import org.apache.qpid.proton.message.Message;
import org.fusesource.hawtbuf.Buffer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Implements the AMQP Transaction Coordinator support to manage local
* transactions between an AMQP client and the broker.
*/
public class AmqpTransactionCoordinator extends AmqpAbstractReceiver {
private static final Logger LOG = LoggerFactory.getLogger(AmqpTransactionCoordinator.class);
private final Set<AmqpSession> txSessions = new HashSet<AmqpSession>();
/**
* Creates a new Transaction coordinator used to manage AMQP transactions.
*
* @param session
* the AmqpSession under which the coordinator was created.
* @param receiver
* the AMQP receiver link endpoint for this coordinator.
*/
public AmqpTransactionCoordinator(AmqpSession session, Receiver endpoint) {
super(session, endpoint);
}
@Override
protected void processDelivery(final Delivery delivery, Buffer deliveryBytes) throws Exception {
Message message = Proton.message();
int offset = deliveryBytes.offset;
int len = deliveryBytes.length;
while (len > 0) {
final int decoded = message.decode(deliveryBytes.data, offset, len);
assert decoded > 0 : "Make progress decoding the message";
offset += decoded;
len -= decoded;
}
final AmqpSession session = (AmqpSession) getEndpoint().getSession().getContext();
final ConnectionId connectionId = session.getConnection().getConnectionId();
final Object action = ((AmqpValue) message.getBody()).getValue();
LOG.debug("COORDINATOR received: {}, [{}]", action, deliveryBytes);
if (action instanceof Declare) {
Declare declare = (Declare) action;
if (declare.getGlobalId() != null) {
throw new Exception("don't know how to handle a declare /w a set GlobalId");
}
LocalTransactionId txId = session.getConnection().getNextTransactionId();
TransactionInfo txInfo = new TransactionInfo(connectionId, txId, TransactionInfo.BEGIN);
session.getConnection().registerTransaction(txId, this);
sendToActiveMQ(txInfo, null);
LOG.trace("started transaction {}", txId);
Declared declared = new Declared();
declared.setTxnId(new Binary(toBytes(txId.getValue())));
delivery.disposition(declared);
delivery.settle();
} else if (action instanceof Discharge) {
final Discharge discharge = (Discharge) action;
final LocalTransactionId txId = new LocalTransactionId(connectionId, toLong(discharge.getTxnId()));
final byte operation;
if (discharge.getFail()) {
LOG.trace("rollback transaction {}", txId);
operation = TransactionInfo.ROLLBACK;
} else {
LOG.trace("commit transaction {}", txId);
operation = TransactionInfo.COMMIT_ONE_PHASE;
}
for (AmqpSession txSession : txSessions) {
if (operation == TransactionInfo.ROLLBACK) {
txSession.rollback(txId);
} else {
txSession.commit(txId);
}
}
txSessions.clear();
session.getConnection().unregisterTransaction(txId);
TransactionInfo txinfo = new TransactionInfo(connectionId, txId, operation);
sendToActiveMQ(txinfo, new ResponseHandler() {
@Override
public void onResponse(AmqpProtocolConverter converter, Response response) throws IOException {
if (response.isException()) {
ExceptionResponse er = (ExceptionResponse) response;
Rejected rejected = new Rejected();
rejected.setError(new ErrorCondition(Symbol.valueOf("failed"), er.getException().getMessage()));
delivery.disposition(rejected);
} else {
delivery.disposition(Accepted.getInstance());
}
LOG.debug("TX: {} settling {}", operation, action);
delivery.settle();
session.pumpProtonToSocket();
}
});
if (operation == TransactionInfo.ROLLBACK) {
session.flushPendingMessages();
}
} else {
throw new Exception("Expected coordinator message type: " + action.getClass());
}
replenishCredit();
}
private void replenishCredit() {
if (getEndpoint().getCredit() <= (getConfiguredReceiverCredit() * .2)) {
LOG.debug("Sending more credit ({}) to transaction coordinator on session {}", getConfiguredReceiverCredit() - getEndpoint().getCredit(), session.getSessionId());
getEndpoint().flow(getConfiguredReceiverCredit() - getEndpoint().getCredit());
session.pumpProtonToSocket();
}
}
@Override
public ActiveMQDestination getDestination() {
return null;
}
@Override
public void setDestination(ActiveMQDestination destination) {
}
public void enlist(AmqpSession session) {
txSessions.add(session);
}
}