Interoperability between AMQP 1.0 and 0-* clients

Question

I'm thinking about introducing QPid Broker-J as an AMQP broker in the architecture we're developing, for it's wide support of different versions of the AMQP protocol.

We would be only producers, while third-party software over which we wouldn't have much control would act as consumer(s). Our producers would be written in C++, so the most sensible thing to do at first seemed to adopt Proton C++ as a client library, which uses the latest AMQP 1.0.

I then read that the 1.0 specification is a lot different from all previous ones and this raises a concern about the interoperability. In example, it doesn't say anything about exchanges.

So, my question is... can the two versions communicate? Do I still have access even from AMQP 1.0 clients to all the concepts I need like exchanges and queue management that are from AMQP 0-* clients? Or should I rather drop the idea of using Proton C++ and adopt another client for an older version (0-9-1 seems like the most commonly supported). Which one, in this case?

I found this vaguely related question and some interoperability documentation about RabbitMQ Clients with QPid Broker-J, but neither of them unfortunately answers my question. Proton's documentation is not that good as well, and I couldn't find anything interesting there either.

Thanks in advance for your time.

Answer 1

In general Qpid Broker-J provides full interoperability between clients of the different AMQP versions as much as it is possible to do so.

In terms of concepts such as exchanges, as you observe, these are not defined in AMQP 1.0 itself, however Qpid Broker-J allows your AMQP 1.0 clients to send messages to exchanges (and also to "consume" directly from an exchange by - in the background - creating a temporary queue and binding it to the exchange).

In terms of queue/exchange management, 0-x clients can continue to use operations like queue.declare or exchange.declare. For AMQP 1.0 clients these commands are not available, however Qpid Broker-J does offer a couple of ways to manage queues for AMQP 1.0 clients. One option would be to use Qpid Broker-J's REST API to create/bind exchanges/queues etc. The other (undocumented) option is to use management messages to the special $management address. This is an implementation of the Draft OASIS AMQP Management specification (which is subject to change, hence it is not documented currently). You can find an example of its use in some of Qpid Broker-J's tests, e.g. org.apache.qpid.systests.jms_1_1.extensions.management.AmqpManagementTest with the test method testCreateQueueOnVirtualHostManagement() giving an example as to how to create a queue over AMQP management for example.

If you have any more questions on Qpid Broker-J I'd suggest mailing the users list for Qpid (users@qpid.apache.org) where the developers would be happy to answer any questions.