On 17/12/13 14:22 +0000, Gordon Sim wrote:
On 12/17/2013 01:53 PM, Flavio Percoco wrote:On 16/12/13 10:37 +0000, Gordon Sim wrote:On 12/12/2013 02:14 PM, Flavio Percoco wrote:I've a draft in my head of how the amqp 1.0 driver could be implemented and how to map the current expectations of the messaging layer to the new protocol.I think a separate thread to discuss this mapping is worth it. There are some critical areas that definitely need more discussionI have also been looking at this, and trying to write up a simple design notes. Some of the questions that occurred to me while doing so are: * Use one link for all sends, with 'to' field set, or use a link for each target?I like this proposal. It keeps messages atomic and isolated from the rest of the environment. The only I can think OTO is: What happens if the node that the reply should go to dies before the reply is sent? Is this something we should be worrying about? I mean, if the node that was waiting for the response dies, I think we'd have bigger problems than just a 'missed response' :D. However, this doesn't mean we couldn't take care of that.I'm afraid I'm not following you here. To clarify the original point, in AMQP 1.0 all messages are sent over a sending link (this is like a subscription, but for senders). You can also set an address per-message. However my view is that using a link per target is more interoperable at present. The spec doesn't really require the routing of messages by 'to' field and consequently not all implementations support it.The point you are making seems to be around reliability(?). I would like to see some definitive statement about expectations in that regard for the API users and for transport implementers, but I think its a separate issue from whether or not to use a single link. (Perhaps the term 'link' is overloaded here, causing the confusion. In AMQP 1.0 a link is something like a subscription, but its a symmetric concept so also covers sending of messages).
I'm sorry, it was indeed a bit confusing. What I'm referring to, which I think is related to the above issue, is that the 'reply-to' field needs to be sent either way. My question was indeed more related to reliability and as you mentioned it needs to be clarified a bit further. I'm sorry for hijacking your question. :) Cheers, FF -- @flaper87 Flavio Percoco
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