Transaction support for message receipt acknowledgement

Transactional sending of messages was already supported in all versions of Habari Client libraries. Some library versions¹ now also support commit and roll back for the acknowledgement of received messages. When a transaction is rolled back or the connection is closed without a commit, messages which have been acknowledged after the transaction start will return to unacknowledged state.

[sourcecode lang=”delphi” highlight=”15,16″]
// receive in a transacted session
Session := Connection.CreateSession(True, amClientAcknowledge);
Queue := Session.CreateQueue(GetQueueName);
Consumer := Session.CreateConsumer(Queue);
Msg := Consumer.Receive(1000);

// process the message
…

// acknowledge the message
Msg.Acknowledge;

…

// in case of critical errors, roll back acknowledgements
Session.Rollback;
[/sourcecode]

Bug fixes and improvements

Bug fixes and improvements included in the next release (planned for Q1/2014):

• Authentication with empty credentials (user / passcode) values fails
• Support for encoded carriage return (“\r”) in STOMP 1.2 headers
• Support for equal signs and colons in STOMP headers
• Support for empty STOMP header values
• Compiler errors with Free Pascal 2.7.1
• Unit tests for wild-card destinations
• Unit tests for queue browser