[zeromq-dev] OpenStack cloud API

[Pieter Hintjens]

On Tue, Aug 3, 2010 at 9:22 AM, Martin Sustrik <sustrik at 250bpm.com> wrote:

> I'm going to write a simple 0MQ/AMQP adapter shortly so 0MQ applications
> will be able to join the OpenStack message bus easily (there's RabbitMQ
> running at it's core).

>From the architecture diagrams it's not clear how far applications
need to speak AMQP; OpenStack provides an API that abstracts the
internals.  From looking at the source code, it's a work in progress,
and I don't see anything about nodes let alone AMQP.

An 0MQ/AMQP adaptor would be useful in any case; the code is well
known. Presumably AMQP/0.9.1?

> However, speaking about communication with existing messaging
> infrastructure, there's a project that would be extremely interesting
> from both adoption and commercial perspective, namely creating a JMS/0MQ
> bridge.
> ...
> If anyone is interested in that kind of thing, I can supply overall
> design of the thing.

If you have an idea how to do this, I'd suggest posting a design
somewhere and adding that to the Labs page.  It's useful to collect
ideas there (also the 0MQ/AMQP adaptor) because people browsing the
site can then see them.

I'd like to see your design proposal and especially how you answer the
reliability model that enterprise JMS turns around.

> Some comments:

Much appreciated!

> 1. Zed's introduction incorporated into the document seems a bit
> superfluous.

Yes, it is... I like the writing but it's redundant.

> 2. The examples should be in C given that accompanying text uses C API.

It's a deliberate choice to make examples in random languages to
emphasize that 0MQ has a single cross-language API.

> 3. Using multi-threaded server as a first example is overly complex IMO.
> Single-threaded server would do. Also, it may be worth of writing in
> Python so that simplicity of 0MQ is even more clearly pronounced.

Probably, yes.  Good point.

> 4. There's a factual error in the part concerning messages. When you
> send a message, your zmq_msg_t object remains empty.

It is a rather complex API... :-)  I'll fix this error.

-Pieter